https://hilbert.math.wisc.edu/wiki/api.php?action=feedcontributions&user=Lmao&feedformat=atomUW-Math Wiki - User contributions [en]2021-06-18T08:41:38ZUser contributionsMediaWiki 1.30.1https://hilbert.math.wisc.edu/wiki/index.php?title=Reading_Seminar_2018-19&diff=16356Reading Seminar 2018-192018-11-07T21:10:40Z<p>Lmao: </p>
<hr />
<div>==Overview==<br />
My (Daniel's) experience has been that reading seminars have diminishing returns: they run out of steam after about 8 lectures on a certain book, as everyone starts falling behind, etc. I was thinking aim broader (rather than deeper), covering 3 books, but with fewer lectures. My idea is to partly cover: Beauville's "Complex Algebraic Surfaces"; Atiyah's "K-theory" (1989 edition); and Harris and Morrison's "Moduli of Curves". We would do about 6-8 lectures on each. This allows us to reboot every two months, which I hope will be mentally refreshing and will allow people who have lost the thread of the book to rejoin. Anyways, it's an experiment!<br />
<br />
Some notes:<br />
<ul><br />
<li>Here is lecture notes from Ravi Vakil on Complex Algebraic Surfaces "http://math.stanford.edu/~vakil/02-245/index.html"<br />
<li> Each book will have a co-organizer: Wanlin Li for Beauville's book; Michael Brown for Atiyah's book; and Rachel Davis for Harris and Mumford's book. Thanks!</li><br />
<li>I left some "Makeup" dates in the schedule with the idea that we would most likely take a week off on those dates. But if we need to miss another date (because of a conflict with a special colloquium or some other event), then we can use those as makeup slots.</li><br />
</ul><br />
<br />
We are experimenting with lots of new formats in this year's seminar. If you aren't happy with how the reading seminar is going, please let one of the organizers (Daniel, Wanlin, Michael, or Rachel) know and we will do our best to get things back on a helpful track.<br />
<br />
==Time and Location==<br />
Talks will be on Fridays from 11:45-12:35 in B325. This semester, Daniel is planning to keep a VERY HARD watch on the clock.<br />
<br />
== Talk Schedule ==<br />
<br />
{| cellpadding="8"<br />
!align="left" | date<br />
!align="left" | speaker<br />
!align="left" | sections<br />
<br />
|-<br />
|September 7<br />
|Wanlin Li<br />
|Beauville I<br />
|-<br />
|September 14<br />
|Rachel Davis<br />
|Beauville II<br />
|-<br />
|September 21<br />
|Brandon Boggess<br />
|Beauville II and III<br />
|-<br />
|September 28<br />
|Mao Li<br />
|Beauville III<br />
|-<br />
|October 5<br />
|Wendy Cheng<br />
|Beauville IV<br />
|-<br />
|October 12<br />
|Soumya Sankar<br />
|Beauville V<br />
|-<br />
|October 19<br />
|David Wagner<br />
|Beauville V and VI<br />
|-<br />
|October 26<br />
|Dan Corey<br />
|Beauville VII and VIII<br />
|-<br />
|November 2<br />
|No Meeting<br />
|Break<br />
|-<br />
|November 9<br />
|Michael Brown<br />
|Atiyah 1 (Overview of goals of the seminar, Section 2.1) <br />
|-<br />
|November 16<br />
|Asvin Gothandaraman<br />
|Atiyah 2 (Section 2.2)<br />
|-<br />
|November 23<br />
|NO MEETING<br />
|Thanksgiving<br />
|-<br />
|November 30<br />
|Daniel Erman<br />
|Atiyah 3 (Section 2.5)<br />
|-<br />
|SEMESETER BREAK<br />
|No meetings<br />
|<br />
|-<br />
|January 25<br />
|Rachel Davis<br />
|Atiyah 4 (Section 2.3, Part 1)<br />
|-<br />
|February 1<br />
|??<br />
|Atiyah 5 (Section 2.3, Part 2)<br />
|-<br />
|February 8<br />
|??<br />
|Atiyah 6 (Section 2.6)<br />
|-<br />
|February 15<br />
|??<br />
|Atiyah 7 (Section 2.7, up to the Thom Isomorphism Theorem. You'll need to double back and say a few words about equivariant K-theory, from Section 2.4 (which we skipped)).<br />
|-<br />
|February 22<br />
|Mao Li<br />
|Algebraic K theory, Localization theorem and flag variety.<br />
|-<br />
|March 1<br />
| Juliette Bruce<br />
|Moduli 1<br />
|-<br />
|March 8<br />
|Niudun Wang<br />
|Moduli 2<br />
|-<br />
|March 15<br />
|Rachel Davis<br />
|Moduli 3<br />
|-<br />
|March 22<br />
|NO MEETING<br />
|Spring recess<br />
|-<br />
|March 29<br />
|??<br />
|Moduli 4<br />
|-<br />
|April 5<br />
|??<br />
|Moduli 5<br />
|-<br />
|April 12<br />
|??<br />
|Moduli 6<br />
|-<br />
|April 19<br />
|??<br />
|Moduli 7<br />
|}<br />
<br />
==How to plan your talk==<br />
One key to giving good talks in a reading seminar is to know how to refocus the material that you read. Instead of going through the chapter lemma by lemma, you should ask: What is the main idea in this section? It could be a theorem, a definition, or even an example. But after reading the section, decide what the most important idea is and be sure to highlight early on.<br />
<br />
You will probably need to skip the proofs--and even the statements--of many of the lemmas and other results in the chapter. This is a good thing! The reason someone attends a talk, as opposed to just reading the material on their own, is because they want to see the material from the perspective of someone who has thought it about carefully.<br />
<br />
Also, make sure to give clear examples.<br />
<br />
<br />
==Feedback on talks==<br />
One of the goals for this semester is to help the speakers learn to give better talks. Here is our plan:<br />
<br />
<li> Feedback session: This is like a streamlined version of what creative writing workshops do. Every week, we reserve 15 minutes (12:35-12:50) for the entire audience to critique that week’s speaker. Comments will be friendly and constructive. A key rule is that the speaker is not allowed to speak until the last 5 minutes.</li><br />
<br />
<li> Partner: We assign a “partner” each week (usually the previous week's speaker). The partner will meet for 20-30 minutes with the speaker in advance to:<br />
<ol> Discuss a plan for the talk. Here the speaker can outline what they see as the main ideas, and the partner can share any wisdom gleaned from their experience the previous week. </ol><br />
<ol> Ask the speaker if there are any particular things that the speaker would like feedback on (e.g. pacing, boardwork, clarity of voice, etc.). </ol><br />
The partner would also take notes during the feedback session, to give the speaker a record of the conversation.<br />
</li><br />
<br />
This is very much an experiment, and while it might be intimidating at first, I actually think it could really help everyone (the speakers and the audience members too).</div>Lmaohttps://hilbert.math.wisc.edu/wiki/index.php?title=Reading_Seminar_2018-19&diff=15993Reading Seminar 2018-192018-09-14T21:30:39Z<p>Lmao: </p>
<hr />
<div>==Overview==<br />
My (Daniel's) experience has been that reading seminars have diminishing returns: they run out of steam after about 8 lectures on a certain book, as everyone starts falling behind, etc. I was thinking aim broader (rather than deeper), covering 3 books, but with fewer lectures. My idea is to partly cover: Beauville's "Complex Algebraic Surfaces"; Atiyah's "K-theory" (1989 edition); and Harris and Morrison's "Moduli of Curves". We would do about 6-8 lectures on each. This allows us to reboot every two months, which I hope will be mentally refreshing and will allow people who have lost the thread of the book to rejoin. Anyways, it's an experiment!<br />
<br />
Some notes:<br />
<ul><br />
<li>Here is lecture notes from Ravi Vakil on Complex Algebraic Surfaces "http://math.stanford.edu/~vakil/02-245/index.html"<br />
<li> Each book will have a co-organizer: Wanlin Li for Beauville's book; Michael Brown for Atiyah's book; and Rachel Davis for Harris and Mumford's book. Thanks!</li><br />
<li>I left some "Makeup" dates in the schedule with the idea that we would most likely take a week off on those dates. But if we need to miss another date (because of a conflict with a special colloquium or some other event), then we can use those as makeup slots.</li><br />
</ul><br />
<br />
We are experimenting with lots of new formats in this year's seminar. If you aren't happy with how the reading seminar is going, please let one of the organizers (Daniel, Wanlin, Michael, or Rachel) know and we will do our best to get things back on a helpful track.<br />
<br />
==Time and Location==<br />
Talks will be on Fridays from 11:45-12:35 in B325. This semester, Daniel is planning to keep a VERY HARD watch on the clock.<br />
<br />
== Talk Schedule ==<br />
<br />
{| cellpadding="8"<br />
!align="left" | date<br />
!align="left" | speaker<br />
!align="left" | sections<br />
<br />
|-<br />
|September 7<br />
|Wanlin Li<br />
|Beauville I<br />
|-<br />
|September 14<br />
|Rachel Davis<br />
|Beauville II<br />
|-<br />
|September 21<br />
|Brandon Boggess<br />
|Beauville II and III<br />
|-<br />
|September 28<br />
|Mao Li<br />
|Beauville III<br />
|-<br />
|October 5<br />
|Wendy Cheng<br />
|Beauville IV<br />
|-<br />
|October 12<br />
|Soumya Sankar<br />
|Beauville V<br />
|-<br />
|October 19<br />
|??<br />
|Beauville V and VI<br />
|-<br />
|October 26<br />
|Dan Corey<br />
|Beauville VII and VIII<br />
|-<br />
|November 2<br />
|??<br />
|Makeup Beauville<br />
|-<br />
|November 9<br />
|Michael Brown<br />
|Atiyah 1 (Overview of goals of the seminar, Section 2.1) <br />
|-<br />
|November 16<br />
|Asvin Gothandaraman<br />
|Atiyah 2 (Section 2.2)<br />
|-<br />
|November 23<br />
|NO MEETING<br />
|Thanksgiving<br />
|-<br />
|November 30<br />
|Daniel Erman<br />
|Atiyah 3 (Section 2.5)<br />
|-<br />
|SEMESETER BREAK<br />
|No meetings<br />
|<br />
|-<br />
|January 29<br />
|??<br />
|Atiyah 4 (Section 2.3, Part 1)<br />
|-<br />
|February 1<br />
|??<br />
|Atiyah 5 (Section 2.3, Part 2)<br />
|-<br />
|February 8<br />
|??<br />
|Atiyah 6 (Section 2.6)<br />
|-<br />
|February 15<br />
|??<br />
|Atiyah 7 (Section 2.7, up to the Thom Isomorphism Theorem)<br />
|-<br />
|February 22<br />
|??<br />
|Makeup<br />
|-<br />
|March 1<br />
| Juliette Bruce<br />
|Moduli 1<br />
|-<br />
|March 8<br />
|Niudun Wang<br />
|Moduli 2<br />
|-<br />
|March 15<br />
|??<br />
|Moduli 3<br />
|-<br />
|March 22<br />
|??<br />
|Moduli 4<br />
|-<br />
|March 29<br />
|??<br />
|Moduli 5<br />
|-<br />
|April 5<br />
|??<br />
|Moduli 6<br />
|-<br />
|April 12<br />
|??<br />
|Moduli 7<br />
|-<br />
|April 19<br />
|??<br />
|Makeup<br />
|}<br />
<br />
==How to plan your talk==<br />
One key to giving good talks in a reading seminar is to know how to refocus the material that you read. Instead of going through the chapter lemma by lemma, you should ask: What is the main idea in this section? It could be a theorem, a definition, or even an example. But after reading the section, decide what the most important idea is and be sure to highlight early on.<br />
<br />
You will probably need to skip the proofs--and even the statements--of many of the lemmas and other results in the chapter. This is a good thing! The reason someone attends a talk, as opposed to just reading the material on their own, is because they want to see the material from the perspective of someone who has thought it about carefully.<br />
<br />
Also, make sure to give clear examples.<br />
<br />
<br />
==Feedback on talks==<br />
One of the goals for this semester is to help the speakers learn to give better talks. Here is our plan:<br />
<br />
<li> Feedback session: This is like a streamlined version of what creative writing workshops do. Every week, we reserve 15 minutes (12:35-12:50) for the entire audience to critique that week’s speaker. Comments will be friendly and constructive. A key rule is that the speaker is not allowed to speak until the last 5 minutes.</li><br />
<br />
<li> Partner: We assign a “partner” each week (usually the previous week's speaker). The partner will meet for 20-30 minutes with the speaker in advance to:<br />
<ol> Discuss a plan for the talk. Here the speaker can outline what they see as the main ideas, and the partner can share any wisdom gleaned from their experience the previous week. </ol><br />
<ol> Ask the speaker if there are any particular things that the speaker would like feedback on (e.g. pacing, boardwork, clarity of voice, etc.). </ol><br />
The partner would also take notes during the feedback session, to give the speaker a record of the conversation.<br />
</li><br />
<br />
This is very much an experiment, and while it might be intimidating at first, I actually think it could really help everyone (the speakers and the audience members too).</div>Lmaohttps://hilbert.math.wisc.edu/wiki/index.php?title=Graduate_Algebraic_Geometry_Seminar_Spring_2018&diff=15281Graduate Algebraic Geometry Seminar Spring 20182018-03-21T00:31:13Z<p>Lmao: </p>
<hr />
<div>'''<br />
'''When:''' Wednesdays 3:40pm<br />
<br />
'''Where:'''Van Vleck B321 (Spring 2018)<br />
[[Image:cat.jpg|thumb|220px| | Lizzie the OFFICIAL mascot of GAGS!!]]<br />
<br />
'''Who:''' All undergraduate and graduate students interested in algebraic geometry, commutative algebra, and related fields are welcome to attend.<br />
<br />
'''Why:''' The purpose of this seminar is to learn algebraic geometry and commutative algebra by giving and listening to talks in a informal setting. Talks are typically accessible to beginning graduate students and take many different forms. Sometimes people present an interesting paper they find. Other times people give a prep talk for the Friday Algebraic Geometry Seminar. Other times people give a series of talks on a topic they have been studying in-depth. Regardless the goal of GAGS is to provide a supportive and inclusive place for all to learn more about algebraic geometry and commutative algebra.<br />
<br />
'''How:'''If you want to get emails regarding time, place, and talk topics ('''which are often assigned quite last minute''') add yourself to the gags mailing list: gags@lists.wisc.edu. The list registration page is [https://admin.lists.wisc.edu/index.php?p=11&l=gags here].<br />
'''<br />
<br />
== Give a talk! ==<br />
We need volunteers to give talks this semester. If you're interested contact [mailto:juliette.bruce@math.wisc.edu Juliette] or [mailto:moises@math.wisc.edu Moisés], or just add yourself to the list (though in that case we might move your talk later without your permission). Beginning graduate students are particularly encouraged to give a talk, since it's a great way to get your feet wet with the material.<br />
<br />
== Being an audience member ==<br />
The goal of GAGS is to create a safe and comfortable space inclusive of all who wish to expand their knowledge of algebraic geometry and commutative algebra. In order to promote such an environment in addition to the standard expectations of respect/kindness all participants are asked to following the following guidelines:<br />
* Do Not Speak For/Over the Speaker: <br />
* Ask Questions Appropriately: <br />
<br />
==The List of Topics that we Made February 2018==<br />
<br />
On February 21st of the Month of February of The 2018th Year of the Seventh Age of The Sun, the People Present at GAGS Compiled Ye Followinge Liste of Topics They Wished to Hear Aboute:<br />
<br />
Feel free to edit the list and/or add references to learn this stuff from.<br />
<br />
* Schubert Calculus, aka how many lines intersect four given lines in three-dimensional space? The answer to this question is prettiest when you think about it as a problem of intersecting subvarieties in the Grassmanian. ''What is the Grassmanian, you say?'' That's probably a talk we should have every year, so you should give it!<br />
<br />
* Kindergarten GAGA. GAGA stands for Algebraic Geometry - Analytic Geometry. Serre wrote a famous paper explaining how the two are related, and you could give an exposition suitable to kindergardeners.<br />
<br />
* Katz and Mazur explanation of what a modular form is. What is it?<br />
<br />
* Kindergarten moduli of curves.<br />
<br />
* What is a dualizing sheaf? What is a dualizing complex? What is Serre duality? What is local duality? Can local duality help us understand Serre duality?<br />
<br />
* Generalizations of Riemann - Roch. (Grothendieck - Riemann - Roch? Hirzebruch - Riemann - Roch?)<br />
<br />
* Hodge theory for babies<br />
<br />
* What is a Néron model?<br />
<br />
* What is a crystal? What does it have to do with D-modules? [http://www.math.harvard.edu/~gaitsgde/grad_2009/SeminarNotes/Nov17-19(Crystals).pdf Here's an encouragingly short set of notes on it].<br />
<br />
* What and why is a dessin d'enfants?<br />
<br />
* DG Schemes.<br />
<br />
<br />
==Ed Dewey's Wish List Of Olde==<br />
<br />
Back in the day Ed and Nathan made this list of topics they wanted to hear. They all sound super duper cool, but it's also true that they had many years of AG behind their backs, so this list might not be very representative of what the GAGS audience wants to hear bout.<br />
<br />
Here are the topics we're '''DYING''' to learn about! Please consider looking into one of these topics and giving one or two GAGS talks.<br />
<br />
===Specifically Vague Topics===<br />
* D-modules 101: basics of D-modules, equivalence between left and right D-modules, pullbacks, pushforwards, maybe the Gauss-Manin Connection. Claude Sabbah's introduction to the subject could be a good place to start.<br />
<br />
* Sheaf operations on D-modules (the point is that then you can get a Fourier-Mukai transform between certain O-modules and certain D-modules, which is more or less how geometric Langlands is supposed to work)<br />
<br />
===Famous Theorems===<br />
<br />
===Interesting Papers & Books===<br />
* ''Symplectic structure of the moduli space of sheaves on an abelian or K3 surface'' - Shigeru Mukai.<br />
<br />
* ''Residues and Duality'' - Robin Hatshorne.<br />
** Have you heard of Serre Duality? Would you like to really understand the nuts and bolts of it and its generalizations? If so this book is for you. (You wouldn't need to read the whole book to give a talk ;).)<br />
<br />
* ''Coherent sheaves on P^n and problems in linear algebra'' - A. A. Beilinson.<br />
** In this two page paper constructs the semi-orthogonal decomposition of the derived category of coherent sheaves on projective space. (This topic is very important, and there are a ton of other resources for this result and the general theory of derived categories.)<br />
<br />
* ''Frobenius splitting and cohomology vanishing for Schubert varieties'' - V.B. Mehta and A. Ramanathan.<br />
** In characteristic p the fact that (x+y)^p=x^p+y^p means that one has the Frobenius morphism, which sends f to f^p. In this paper the authors introduce the notion of what it means for a variety to be Frobenius split, and use this to prove certain cohomologcal vanishing results for Schubert varieties. Since then Frobenius splitting -- and its related cousins (F-regularity, strong F-regularity, F-purity, etc.) have played large roles in geometry and algebra in characteristic p. This is a good place to get a sense for what kicked all this stuff off! <br />
<br />
* ''Schubert Calculus'' - S. L. Kleiman and Dan Laksov.<br />
** An introduction to Schubert calculus suitable for those of all ages. I am told the paper essentially only uses linear algebra!<br />
<br />
* ''Rational Isogenies of Prime Degree'' - Barry Mazur.<br />
** In this paper Mazur classifies all isogenies of rational elliptic curves of prime order. As a result of this he deduces his famous result that the torsion subgroup of an elliptic curve (over Q) is one of 15 abelian groups. This definitely stares into the land of number theory, but certainly would still be of interest to many.<br />
<br />
* ''Esquisse d’une programme'' - Alexander Grothendieck.<br />
** Originating from a grant proposal in the mid 1980's this famous paper outlines a tantalizing research program, which seeks to tie numerous different areas of math (algebraic geometry, Teichmuller theory, Galois theory, etc.) together. This is where Grothendieck introduced his famous Lego game and dessin d'enfant. While just a research proposal this paper has seemingly inspired a ton of cool math, and will allow you to "blow peoples’ minds". (The original paper is in French, but there are English translations out there.)<br />
<br />
* ''Géométrie algébraique et géométrie analytique'' - J.P. Serre.<br />
** A projective variety X over the complex numbers has two lives, an algebraic and an analytic, depending on which topology one wishes to work with. That is one can think about X as a complex manifold and work with holomorphic functions or as an algebraic variety and work with regular functions. Hence to any complex projective variety we have two sheaf theories and as a result two cohomology theories. In this famous paper Serre compares these two and shows they are in fact the same. (''Note: This is a super fundamental result that is used all the time; normally in the following way: Uhh... What do you mean by cohomology? Well by GAGA or something it doesn't really mater.) (The original paper is in French, but there are English translations out there.)<br />
<br />
* ''Limit linear series: Basic theory''- David Eisenbud and Joe Harris.<br />
** One of the more profitable tools -- especially when studying moduli spaces -- in a geometers tool box is the theory of degenerations. However, sometimes we care about more than just the variety we are degenerating and want to keep track of things like vector/line bundles. In this paper Eisenbud and Harris develop the theory of degenerating a curve together with a linear series. From this they prove a ton of cool results: M_g is of general type for g>24, Brill-Noether theory, etc.<br />
<br />
* ''Picard Groups of Moduli Problems'' - David Mumford.<br />
** This paper is essentially the origin of algebraic stacks.<br />
<br />
* ''The Structure of Algebraic Threefolds: An Introduction to Mori's Program'' - Janos Kollar<br />
** This paper is an introduction to Mori's famous ``minimal model'' program, which is a far reaching program seeking to understand the birational geometry of higher dimensional varieties. <br />
<br />
* ''Cayley-Bacharach Formulas'' - Qingchun Ren, Jürgen Richter-Gebert, Bernd Sturmfels.<br />
** A classical result we all learn in a first semester of algebraic geometry is that 5 points in the plane (in general position) determine a unique plane conic. One can similarly show that 9 (general) points in the plane determine a unique plane cubic curve. This paper tries to answer the question: ``What is equation for this cubic curve?''.<br />
<br />
* ''On Varieties of Minimal Degree (A Centennial Approach)'' - David Eisenbud and Joe Harris.<br />
** Suppose X is a projective variety embedded in projective space so that X is not contained in any hyperplane. By projecting from general points one can see that the degree of X is at least codim(X)+1. This paper discusses the classification of varieties that achieve this lower degree bound i.e. varieties of minimal degree. This topic is quite classical and the paper seems to contain a nice mixture of classical and modern geometry.<br />
<br />
* ''The Gromov-Witten potential associated to a TCFT'' - Kevin J. Costello.<br />
** This seems incredibly interesting, but fairing warning this paper has been described as ''highly technical'', which considering it uses A-infinity algebras and the derived category of a Calabi-Yau seems like a reasonable description. (This paper may be covered in Caldararu's Spring 2017 topics course.)<br />
__NOTOC__<br />
<br />
== Spring 2017 ==<br />
<br />
<center><br />
{| style="color:black; font-size:120%" border="0" cellpadding="14" cellspacing="5"<br />
|-<br />
| bgcolor="#D0D0D0" width="300" align="center"|'''Date'''<br />
| bgcolor="#A6B658" width="300" align="center"|'''Speaker'''<br />
| bgcolor="#BCD2EE" width="300" align="center"|'''Title (click to see abstract)'''<br />
|-<br />
| bgcolor="#E0E0E0"| February 14<br />
| bgcolor="#C6D46E"| Moisés Herradón Cueto<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#February 14| Fun with commutative groups]]<br />
|-<br />
| bgcolor="#E0E0E0"| February 21<br />
| bgcolor="#C6D46E"| Moisés Herradón Cueto<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#February 21| <math>\mathcal F</math>un with commutative groups]]<br />
|-<br />
| bgcolor="#E0E0E0"| February 28<br />
| bgcolor="#C6D46E"| Dima Arinkin<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#February 28| ODEs: algebraic vs analytic vs formal]]<br />
|-<br />
| bgcolor="#E0E0E0"| March 7<br />
| bgcolor="#C6D46E"| Vladimir Sotirov<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#March 7| Topology of Affine Schemes]]<br />
|-<br />
| bgcolor="#E0E0E0"| March 14<br />
| bgcolor="#C6D46E"| David Wagner<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#March 14| Derived Quot Schemes]]<br />
|-<br />
| bgcolor="#E0E0E0"| March 21<br />
| bgcolor="#C6D46E"| Mao Li<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#March 21| D modules in prime characteristic]]<br />
|-<br />
| bgcolor="#E0E0E0"| March 28<br />
| bgcolor="#C6D46E"| Spring break<br />
| bgcolor="#BCE2FE"| Whoo!<br />
|-<br />
| bgcolor="#E0E0E0"| April 4<br />
| bgcolor="#C6D46E"| Rachel Davis<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#April 4| TBD]]<br />
|-<br />
| bgcolor="#E0E0E0"| April 11<br />
| bgcolor="#C6D46E"| Brandon Boggess<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#April 11| TBD]]<br />
|-<br />
| bgcolor="#E0E0E0"| April 18<br />
| bgcolor="#C6D46E"| Soumya Sankar<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#April 18| TBD]]<br />
|-<br />
| bgcolor="#E0E0E0"| April 25<br />
| bgcolor="#C6D46E"| Solly Parenti<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#April 25| TBD]]<br />
|-<br />
| bgcolor="#E0E0E0"| May 2<br />
| bgcolor="#C6D46E"| Mao Li<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#May 2| D-modules and Hecke algebra]]<br />
|}<br />
</center><br />
<br />
== February 14 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''Moisés Herradón Cueto'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: Fun with commutative groups<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
My goal is to next week talk about Gerard Laumon's preprint ''Transformation de Fourier généralisée'', which will encapsulate all the Fourier transforms I can name (which for me includes the Fourier transform for D-modules on affine space, the Mellin transform, the Fourier-Mukai transform for abelian varieties and the rare John Mahoney transform between modules on the punctured line and vector spaces with a Z-action) into one crazy package.<br />
<br />
In order to achieve this altered mental state, we will have to rethink all our preconceptions, and rediscover algebraic groups, make sense of Cartier duality for them, define formal groups along the way, and see how duality of Abelian varieties relates to Cartier duality. If you come to the talk in an already in this altered mental state, then hopefully I'll do some examples that you've been too lazy to work out for yourself.<br />
<br />
|} <br />
</center><br />
<br />
== February 21 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''<math>\mathcal F</math>un with commutative groups'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: <math>\mathcal F</math>un with commutative groups<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
I will talk about how last week's Cartier duality relates to duality for abelian varieties. Then we will see how this allows us to take certain complexes of groups which are self dual, going back to altered mental states which are now derived.<br />
<br />
If we're going to Fourier transform something, it should be a sheaf, but what is even a sheaf on a complex of groups? Once we see what it should be, I will handwave what the Fourier transform is and give a bunch of concrete examples.<br />
<br />
|} <br />
</center><br />
<br />
== February 28 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''Dima Arinkin'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: ODEs: algebraic vs analytic vs formal<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
Linear ordinary differential equations (or, as they are known geometrically, bundles with connections on Riemann surfaces) can be studied from many directions. In algebraic geometry, the goal is ''to classify'' equations rather than ''to solve'' them. The classification can be<br />
done in different settings: algebraic, analytic, or formal; each setting has its advantages and disadvantages. However, for one of the most<br />
important class of equations (equations with regular singularities aka Fuchsian equations) the three approaches agree, leading to a rich <br />
and beautiful picture. <br />
<br />
In my talk, I will sketch the algebraic theory of differential equations, focusing on equations with regular singularities. (I do not expect to have time<br />
for irregular singularities.) The talk is related to my topics course on D-modules, but it does not rely on the topics course.<br />
|} <br />
</center><br />
<br />
== March 7 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''Vladimir Sotirov'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: Topology of Affine Schemes<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
I will explain in what sense flat morphisms of (affine) schemes are the correct analogue of open maps of topological spaces, and then use that to explain how surjectivity in the sense of Zariski spectra corresponds to surjectivity of functors of points.<br />
<br />
|} <br />
</center><br />
<br />
== March 14 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''David Wagner'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: Derived Quot Schemes<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
The titular paper of Ciocan-Fontanine & Kapranov constructs a "derived" version of Grothendieck's Quot scheme, whose degree zero truncation is the ordinary Quot scheme, and whose tangent space at each k-point consists higher Ext's. In this talk, we will talk about what is meant by "derived" in modern AG and why you might want a derived Quot scheme. In the remaining time, we will give a (hopefully transparent) description of how CF&K construct RQuot.<br />
<br />
|} <br />
</center><br />
<br />
== March 21 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''Mao Li'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: D-modules in prime characteristic<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
The usual theory of D-modules concerns itself with sheaves and varieties over complex numbers. In this talk I'm going to consider its characteristic p analogue. The new feature is that the ring of differential operators has a large center. By using this extra information we can give a more precise description about the ring of differential operators, namely it has a canonical structure of an Azumaya algebra over the twisted cotangent bundle. This has lots of applications in algebraic geometry and representation theory. <br />
<br />
|} <br />
</center><br />
<br />
== April 4 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''TBD'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: TBD<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
TBD<br />
<br />
|} <br />
</center><br />
<br />
== April 11 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''TBD'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: TBD<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
TBD<br />
<br />
|} <br />
</center><br />
<br />
== April 18 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''TBD'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: TBD<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
TBD<br />
<br />
|} <br />
</center><br />
<br />
== April 25 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''TBD'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: TBD<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
TBD<br />
<br />
|} <br />
</center><br />
<br />
== May 2 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''TBD'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: TBD<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
TBD<br />
<br />
|} <br />
</center><br />
<br />
<br />
== Organizers' Contact Info ==<br />
[http://www.math.wisc.edu/~juliettebruce Juliette Bruce]<br />
<br />
[http://www.math.wisc.edu/~clement Nathan Clement]<br />
<br />
[https://www.math.wisc.edu/~moises Moisés Herradón Cueto]<br />
<br />
== Past Semesters ==<br />
[https://www.math.wisc.edu/wiki/index.php/Graduate_Algebraic_Geometry_Seminar_Fall_2017 Fall 2017]<br />
<br />
[https://www.math.wisc.edu/wiki/index.php/Graduate_Algebraic_Geometry_Seminar_Spring_2017 Spring 2017]<br />
<br />
[https://www.math.wisc.edu/wiki/index.php/Graduate_Algebraic_Geometry_Seminar_Fall_2016 Fall 2016]<br />
<br />
[https://www.math.wisc.edu/wiki/index.php/Graduate_Algebraic_Geometry_Seminar_Spring_2016 Spring 2016]<br />
<br />
[https://www.math.wisc.edu/wiki/index.php/Graduate_Algebraic_Geometry_Seminar_(Fall_2015) Fall 2015]</div>Lmaohttps://hilbert.math.wisc.edu/wiki/index.php?title=Graduate_Algebraic_Geometry_Seminar_Spring_2018&diff=15280Graduate Algebraic Geometry Seminar Spring 20182018-03-20T21:31:53Z<p>Lmao: </p>
<hr />
<div>'''<br />
'''When:''' Wednesdays 3:40pm<br />
<br />
'''Where:'''Van Vleck B321 (Spring 2018)<br />
[[Image:cat.jpg|thumb|220px| | Lizzie the OFFICIAL mascot of GAGS!!]]<br />
<br />
'''Who:''' All undergraduate and graduate students interested in algebraic geometry, commutative algebra, and related fields are welcome to attend.<br />
<br />
'''Why:''' The purpose of this seminar is to learn algebraic geometry and commutative algebra by giving and listening to talks in a informal setting. Talks are typically accessible to beginning graduate students and take many different forms. Sometimes people present an interesting paper they find. Other times people give a prep talk for the Friday Algebraic Geometry Seminar. Other times people give a series of talks on a topic they have been studying in-depth. Regardless the goal of GAGS is to provide a supportive and inclusive place for all to learn more about algebraic geometry and commutative algebra.<br />
<br />
'''How:'''If you want to get emails regarding time, place, and talk topics ('''which are often assigned quite last minute''') add yourself to the gags mailing list: gags@lists.wisc.edu. The list registration page is [https://admin.lists.wisc.edu/index.php?p=11&l=gags here].<br />
'''<br />
<br />
== Give a talk! ==<br />
We need volunteers to give talks this semester. If you're interested contact [mailto:juliette.bruce@math.wisc.edu Juliette] or [mailto:moises@math.wisc.edu Moisés], or just add yourself to the list (though in that case we might move your talk later without your permission). Beginning graduate students are particularly encouraged to give a talk, since it's a great way to get your feet wet with the material.<br />
<br />
== Being an audience member ==<br />
The goal of GAGS is to create a safe and comfortable space inclusive of all who wish to expand their knowledge of algebraic geometry and commutative algebra. In order to promote such an environment in addition to the standard expectations of respect/kindness all participants are asked to following the following guidelines:<br />
* Do Not Speak For/Over the Speaker: <br />
* Ask Questions Appropriately: <br />
<br />
==The List of Topics that we Made February 2018==<br />
<br />
On February 21st of the Month of February of The 2018th Year of the Seventh Age of The Sun, the People Present at GAGS Compiled Ye Followinge Liste of Topics They Wished to Hear Aboute:<br />
<br />
Feel free to edit the list and/or add references to learn this stuff from.<br />
<br />
* Schubert Calculus, aka how many lines intersect four given lines in three-dimensional space? The answer to this question is prettiest when you think about it as a problem of intersecting subvarieties in the Grassmanian. ''What is the Grassmanian, you say?'' That's probably a talk we should have every year, so you should give it!<br />
<br />
* Kindergarten GAGA. GAGA stands for Algebraic Geometry - Analytic Geometry. Serre wrote a famous paper explaining how the two are related, and you could give an exposition suitable to kindergardeners.<br />
<br />
* Katz and Mazur explanation of what a modular form is. What is it?<br />
<br />
* Kindergarten moduli of curves.<br />
<br />
* What is a dualizing sheaf? What is a dualizing complex? What is Serre duality? What is local duality? Can local duality help us understand Serre duality?<br />
<br />
* Generalizations of Riemann - Roch. (Grothendieck - Riemann - Roch? Hirzebruch - Riemann - Roch?)<br />
<br />
* Hodge theory for babies<br />
<br />
* What is a Néron model?<br />
<br />
* What is a crystal? What does it have to do with D-modules? [http://www.math.harvard.edu/~gaitsgde/grad_2009/SeminarNotes/Nov17-19(Crystals).pdf Here's an encouragingly short set of notes on it].<br />
<br />
* What and why is a dessin d'enfants?<br />
<br />
* DG Schemes.<br />
<br />
<br />
==Ed Dewey's Wish List Of Olde==<br />
<br />
Back in the day Ed and Nathan made this list of topics they wanted to hear. They all sound super duper cool, but it's also true that they had many years of AG behind their backs, so this list might not be very representative of what the GAGS audience wants to hear bout.<br />
<br />
Here are the topics we're '''DYING''' to learn about! Please consider looking into one of these topics and giving one or two GAGS talks.<br />
<br />
===Specifically Vague Topics===<br />
* D-modules 101: basics of D-modules, equivalence between left and right D-modules, pullbacks, pushforwards, maybe the Gauss-Manin Connection. Claude Sabbah's introduction to the subject could be a good place to start.<br />
<br />
* Sheaf operations on D-modules (the point is that then you can get a Fourier-Mukai transform between certain O-modules and certain D-modules, which is more or less how geometric Langlands is supposed to work)<br />
<br />
===Famous Theorems===<br />
<br />
===Interesting Papers & Books===<br />
* ''Symplectic structure of the moduli space of sheaves on an abelian or K3 surface'' - Shigeru Mukai.<br />
<br />
* ''Residues and Duality'' - Robin Hatshorne.<br />
** Have you heard of Serre Duality? Would you like to really understand the nuts and bolts of it and its generalizations? If so this book is for you. (You wouldn't need to read the whole book to give a talk ;).)<br />
<br />
* ''Coherent sheaves on P^n and problems in linear algebra'' - A. A. Beilinson.<br />
** In this two page paper constructs the semi-orthogonal decomposition of the derived category of coherent sheaves on projective space. (This topic is very important, and there are a ton of other resources for this result and the general theory of derived categories.)<br />
<br />
* ''Frobenius splitting and cohomology vanishing for Schubert varieties'' - V.B. Mehta and A. Ramanathan.<br />
** In characteristic p the fact that (x+y)^p=x^p+y^p means that one has the Frobenius morphism, which sends f to f^p. In this paper the authors introduce the notion of what it means for a variety to be Frobenius split, and use this to prove certain cohomologcal vanishing results for Schubert varieties. Since then Frobenius splitting -- and its related cousins (F-regularity, strong F-regularity, F-purity, etc.) have played large roles in geometry and algebra in characteristic p. This is a good place to get a sense for what kicked all this stuff off! <br />
<br />
* ''Schubert Calculus'' - S. L. Kleiman and Dan Laksov.<br />
** An introduction to Schubert calculus suitable for those of all ages. I am told the paper essentially only uses linear algebra!<br />
<br />
* ''Rational Isogenies of Prime Degree'' - Barry Mazur.<br />
** In this paper Mazur classifies all isogenies of rational elliptic curves of prime order. As a result of this he deduces his famous result that the torsion subgroup of an elliptic curve (over Q) is one of 15 abelian groups. This definitely stares into the land of number theory, but certainly would still be of interest to many.<br />
<br />
* ''Esquisse d’une programme'' - Alexander Grothendieck.<br />
** Originating from a grant proposal in the mid 1980's this famous paper outlines a tantalizing research program, which seeks to tie numerous different areas of math (algebraic geometry, Teichmuller theory, Galois theory, etc.) together. This is where Grothendieck introduced his famous Lego game and dessin d'enfant. While just a research proposal this paper has seemingly inspired a ton of cool math, and will allow you to "blow peoples’ minds". (The original paper is in French, but there are English translations out there.)<br />
<br />
* ''Géométrie algébraique et géométrie analytique'' - J.P. Serre.<br />
** A projective variety X over the complex numbers has two lives, an algebraic and an analytic, depending on which topology one wishes to work with. That is one can think about X as a complex manifold and work with holomorphic functions or as an algebraic variety and work with regular functions. Hence to any complex projective variety we have two sheaf theories and as a result two cohomology theories. In this famous paper Serre compares these two and shows they are in fact the same. (''Note: This is a super fundamental result that is used all the time; normally in the following way: Uhh... What do you mean by cohomology? Well by GAGA or something it doesn't really mater.) (The original paper is in French, but there are English translations out there.)<br />
<br />
* ''Limit linear series: Basic theory''- David Eisenbud and Joe Harris.<br />
** One of the more profitable tools -- especially when studying moduli spaces -- in a geometers tool box is the theory of degenerations. However, sometimes we care about more than just the variety we are degenerating and want to keep track of things like vector/line bundles. In this paper Eisenbud and Harris develop the theory of degenerating a curve together with a linear series. From this they prove a ton of cool results: M_g is of general type for g>24, Brill-Noether theory, etc.<br />
<br />
* ''Picard Groups of Moduli Problems'' - David Mumford.<br />
** This paper is essentially the origin of algebraic stacks.<br />
<br />
* ''The Structure of Algebraic Threefolds: An Introduction to Mori's Program'' - Janos Kollar<br />
** This paper is an introduction to Mori's famous ``minimal model'' program, which is a far reaching program seeking to understand the birational geometry of higher dimensional varieties. <br />
<br />
* ''Cayley-Bacharach Formulas'' - Qingchun Ren, Jürgen Richter-Gebert, Bernd Sturmfels.<br />
** A classical result we all learn in a first semester of algebraic geometry is that 5 points in the plane (in general position) determine a unique plane conic. One can similarly show that 9 (general) points in the plane determine a unique plane cubic curve. This paper tries to answer the question: ``What is equation for this cubic curve?''.<br />
<br />
* ''On Varieties of Minimal Degree (A Centennial Approach)'' - David Eisenbud and Joe Harris.<br />
** Suppose X is a projective variety embedded in projective space so that X is not contained in any hyperplane. By projecting from general points one can see that the degree of X is at least codim(X)+1. This paper discusses the classification of varieties that achieve this lower degree bound i.e. varieties of minimal degree. This topic is quite classical and the paper seems to contain a nice mixture of classical and modern geometry.<br />
<br />
* ''The Gromov-Witten potential associated to a TCFT'' - Kevin J. Costello.<br />
** This seems incredibly interesting, but fairing warning this paper has been described as ''highly technical'', which considering it uses A-infinity algebras and the derived category of a Calabi-Yau seems like a reasonable description. (This paper may be covered in Caldararu's Spring 2017 topics course.)<br />
__NOTOC__<br />
<br />
== Spring 2017 ==<br />
<br />
<center><br />
{| style="color:black; font-size:120%" border="0" cellpadding="14" cellspacing="5"<br />
|-<br />
| bgcolor="#D0D0D0" width="300" align="center"|'''Date'''<br />
| bgcolor="#A6B658" width="300" align="center"|'''Speaker'''<br />
| bgcolor="#BCD2EE" width="300" align="center"|'''Title (click to see abstract)'''<br />
|-<br />
| bgcolor="#E0E0E0"| February 14<br />
| bgcolor="#C6D46E"| Moisés Herradón Cueto<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#February 14| Fun with commutative groups]]<br />
|-<br />
| bgcolor="#E0E0E0"| February 21<br />
| bgcolor="#C6D46E"| Moisés Herradón Cueto<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#February 21| <math>\mathcal F</math>un with commutative groups]]<br />
|-<br />
| bgcolor="#E0E0E0"| February 28<br />
| bgcolor="#C6D46E"| Dima Arinkin<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#February 28| ODEs: algebraic vs analytic vs formal]]<br />
|-<br />
| bgcolor="#E0E0E0"| March 7<br />
| bgcolor="#C6D46E"| Vladimir Sotirov<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#March 7| Topology of Affine Schemes]]<br />
|-<br />
| bgcolor="#E0E0E0"| March 14<br />
| bgcolor="#C6D46E"| David Wagner<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#March 14| Derived Quot Schemes]]<br />
|-<br />
| bgcolor="#E0E0E0"| March 21<br />
| bgcolor="#C6D46E"| Mao Li<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#March 21| D modules in prime characteristic]]<br />
|-<br />
| bgcolor="#E0E0E0"| March 28<br />
| bgcolor="#C6D46E"| Spring break<br />
| bgcolor="#BCE2FE"| Whoo!<br />
|-<br />
| bgcolor="#E0E0E0"| April 4<br />
| bgcolor="#C6D46E"| Rachel Davis<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#April 4| TBD]]<br />
|-<br />
| bgcolor="#E0E0E0"| April 11<br />
| bgcolor="#C6D46E"| Brandon Boggess<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#April 11| TBD]]<br />
|-<br />
| bgcolor="#E0E0E0"| April 18<br />
| bgcolor="#C6D46E"| Soumya Sankar<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#April 18| TBD]]<br />
|-<br />
| bgcolor="#E0E0E0"| April 25<br />
| bgcolor="#C6D46E"| Solly Parenti<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#April 25| TBD]]<br />
|-<br />
| bgcolor="#E0E0E0"| May 2<br />
| bgcolor="#C6D46E"| Mao Li<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#May 2| TBD]]<br />
|}<br />
</center><br />
<br />
== February 14 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''Moisés Herradón Cueto'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: Fun with commutative groups<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
My goal is to next week talk about Gerard Laumon's preprint ''Transformation de Fourier généralisée'', which will encapsulate all the Fourier transforms I can name (which for me includes the Fourier transform for D-modules on affine space, the Mellin transform, the Fourier-Mukai transform for abelian varieties and the rare John Mahoney transform between modules on the punctured line and vector spaces with a Z-action) into one crazy package.<br />
<br />
In order to achieve this altered mental state, we will have to rethink all our preconceptions, and rediscover algebraic groups, make sense of Cartier duality for them, define formal groups along the way, and see how duality of Abelian varieties relates to Cartier duality. If you come to the talk in an already in this altered mental state, then hopefully I'll do some examples that you've been too lazy to work out for yourself.<br />
<br />
|} <br />
</center><br />
<br />
== February 21 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''<math>\mathcal F</math>un with commutative groups'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: <math>\mathcal F</math>un with commutative groups<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
I will talk about how last week's Cartier duality relates to duality for abelian varieties. Then we will see how this allows us to take certain complexes of groups which are self dual, going back to altered mental states which are now derived.<br />
<br />
If we're going to Fourier transform something, it should be a sheaf, but what is even a sheaf on a complex of groups? Once we see what it should be, I will handwave what the Fourier transform is and give a bunch of concrete examples.<br />
<br />
|} <br />
</center><br />
<br />
== February 28 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''Dima Arinkin'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: ODEs: algebraic vs analytic vs formal<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
Linear ordinary differential equations (or, as they are known geometrically, bundles with connections on Riemann surfaces) can be studied from many directions. In algebraic geometry, the goal is ''to classify'' equations rather than ''to solve'' them. The classification can be<br />
done in different settings: algebraic, analytic, or formal; each setting has its advantages and disadvantages. However, for one of the most<br />
important class of equations (equations with regular singularities aka Fuchsian equations) the three approaches agree, leading to a rich <br />
and beautiful picture. <br />
<br />
In my talk, I will sketch the algebraic theory of differential equations, focusing on equations with regular singularities. (I do not expect to have time<br />
for irregular singularities.) The talk is related to my topics course on D-modules, but it does not rely on the topics course.<br />
|} <br />
</center><br />
<br />
== March 7 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''Vladimir Sotirov'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: Topology of Affine Schemes<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
I will explain in what sense flat morphisms of (affine) schemes are the correct analogue of open maps of topological spaces, and then use that to explain how surjectivity in the sense of Zariski spectra corresponds to surjectivity of functors of points.<br />
<br />
|} <br />
</center><br />
<br />
== March 14 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''David Wagner'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: Derived Quot Schemes<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
The titular paper of Ciocan-Fontanine & Kapranov constructs a "derived" version of Grothendieck's Quot scheme, whose degree zero truncation is the ordinary Quot scheme, and whose tangent space at each k-point consists higher Ext's. In this talk, we will talk about what is meant by "derived" in modern AG and why you might want a derived Quot scheme. In the remaining time, we will give a (hopefully transparent) description of how CF&K construct RQuot.<br />
<br />
|} <br />
</center><br />
<br />
== March 21 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''Mao Li'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: D-modules in prime characteristic<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
The usual theory of D-modules concerns itself with sheaves and varieties over complex numbers. In this talk I'm going to consider its characteristic p analogue. The new feature is that the ring of differential operators has a large center. By using this extra information we can give a more precise description about the ring of differential operators, namely it has a canonical structure of an Azumaya algebra over the twisted cotangent bundle. This has lots of applications in algebraic geometry and representation theory. <br />
<br />
|} <br />
</center><br />
<br />
== April 4 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''TBD'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: TBD<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
TBD<br />
<br />
|} <br />
</center><br />
<br />
== April 11 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''TBD'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: TBD<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
TBD<br />
<br />
|} <br />
</center><br />
<br />
== April 18 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''TBD'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: TBD<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
TBD<br />
<br />
|} <br />
</center><br />
<br />
== April 25 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''TBD'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: TBD<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
TBD<br />
<br />
|} <br />
</center><br />
<br />
== May 2 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''TBD'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: TBD<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
TBD<br />
<br />
|} <br />
</center><br />
<br />
<br />
== Organizers' Contact Info ==<br />
[http://www.math.wisc.edu/~juliettebruce Juliette Bruce]<br />
<br />
[http://www.math.wisc.edu/~clement Nathan Clement]<br />
<br />
[https://www.math.wisc.edu/~moises Moisés Herradón Cueto]<br />
<br />
== Past Semesters ==<br />
[https://www.math.wisc.edu/wiki/index.php/Graduate_Algebraic_Geometry_Seminar_Fall_2017 Fall 2017]<br />
<br />
[https://www.math.wisc.edu/wiki/index.php/Graduate_Algebraic_Geometry_Seminar_Spring_2017 Spring 2017]<br />
<br />
[https://www.math.wisc.edu/wiki/index.php/Graduate_Algebraic_Geometry_Seminar_Fall_2016 Fall 2016]<br />
<br />
[https://www.math.wisc.edu/wiki/index.php/Graduate_Algebraic_Geometry_Seminar_Spring_2016 Spring 2016]<br />
<br />
[https://www.math.wisc.edu/wiki/index.php/Graduate_Algebraic_Geometry_Seminar_(Fall_2015) Fall 2015]</div>Lmaohttps://hilbert.math.wisc.edu/wiki/index.php?title=Graduate_Algebraic_Geometry_Seminar_Spring_2018&diff=15264Graduate Algebraic Geometry Seminar Spring 20182018-03-16T02:37:34Z<p>Lmao: </p>
<hr />
<div>'''<br />
'''When:''' Wednesdays 3:40pm<br />
<br />
'''Where:'''Van Vleck B321 (Spring 2018)<br />
[[Image:cat.jpg|thumb|220px| | Lizzie the OFFICIAL mascot of GAGS!!]]<br />
<br />
'''Who:''' All undergraduate and graduate students interested in algebraic geometry, commutative algebra, and related fields are welcome to attend.<br />
<br />
'''Why:''' The purpose of this seminar is to learn algebraic geometry and commutative algebra by giving and listening to talks in a informal setting. Talks are typically accessible to beginning graduate students and take many different forms. Sometimes people present an interesting paper they find. Other times people give a prep talk for the Friday Algebraic Geometry Seminar. Other times people give a series of talks on a topic they have been studying in-depth. Regardless the goal of GAGS is to provide a supportive and inclusive place for all to learn more about algebraic geometry and commutative algebra.<br />
<br />
'''How:'''If you want to get emails regarding time, place, and talk topics ('''which are often assigned quite last minute''') add yourself to the gags mailing list: gags@lists.wisc.edu. The list registration page is [https://admin.lists.wisc.edu/index.php?p=11&l=gags here].<br />
'''<br />
<br />
== Give a talk! ==<br />
We need volunteers to give talks this semester. If you're interested contact [mailto:juliette.bruce@math.wisc.edu Juliette] or [mailto:moises@math.wisc.edu Moisés], or just add yourself to the list (though in that case we might move your talk later without your permission). Beginning graduate students are particularly encouraged to give a talk, since it's a great way to get your feet wet with the material.<br />
<br />
== Being an audience member ==<br />
The goal of GAGS is to create a safe and comfortable space inclusive of all who wish to expand their knowledge of algebraic geometry and commutative algebra. In order to promote such an environment in addition to the standard expectations of respect/kindness all participants are asked to following the following guidelines:<br />
* Do Not Speak For/Over the Speaker: <br />
* Ask Questions Appropriately: <br />
<br />
==The List of Topics that we Made February 2018==<br />
<br />
On February 21st of the Month of February of The 2018th Year of the Seventh Age of The Sun, the People Present at GAGS Compiled Ye Followinge Liste of Topics They Wished to Hear Aboute:<br />
<br />
Feel free to edit the list and/or add references to learn this stuff from.<br />
<br />
* Schubert Calculus, aka how many lines intersect four given lines in three-dimensional space? The answer to this question is prettiest when you think about it as a problem of intersecting subvarieties in the Grassmanian. ''What is the Grassmanian, you say?'' That's probably a talk we should have every year, so you should give it!<br />
<br />
* Kindergarten GAGA. GAGA stands for Algebraic Geometry - Analytic Geometry. Serre wrote a famous paper explaining how the two are related, and you could give an exposition suitable to kindergardeners.<br />
<br />
* Katz and Mazur explanation of what a modular form is. What is it?<br />
<br />
* Kindergarten moduli of curves.<br />
<br />
* What is a dualizing sheaf? What is a dualizing complex? What is Serre duality? What is local duality? Can local duality help us understand Serre duality?<br />
<br />
* Generalizations of Riemann - Roch. (Grothendieck - Riemann - Roch? Hirzebruch - Riemann - Roch?)<br />
<br />
* Hodge theory for babies<br />
<br />
* What is a Néron model?<br />
<br />
* What is a crystal? What does it have to do with D-modules? [http://www.math.harvard.edu/~gaitsgde/grad_2009/SeminarNotes/Nov17-19(Crystals).pdf Here's an encouragingly short set of notes on it].<br />
<br />
* What and why is a dessin d'enfants?<br />
<br />
* DG Schemes.<br />
<br />
<br />
==Ed Dewey's Wish List Of Olde==<br />
<br />
Back in the day Ed and Nathan made this list of topics they wanted to hear. They all sound super duper cool, but it's also true that they had many years of AG behind their backs, so this list might not be very representative of what the GAGS audience wants to hear bout.<br />
<br />
Here are the topics we're '''DYING''' to learn about! Please consider looking into one of these topics and giving one or two GAGS talks.<br />
<br />
===Specifically Vague Topics===<br />
* D-modules 101: basics of D-modules, equivalence between left and right D-modules, pullbacks, pushforwards, maybe the Gauss-Manin Connection. Claude Sabbah's introduction to the subject could be a good place to start.<br />
<br />
* Sheaf operations on D-modules (the point is that then you can get a Fourier-Mukai transform between certain O-modules and certain D-modules, which is more or less how geometric Langlands is supposed to work)<br />
<br />
===Famous Theorems===<br />
<br />
===Interesting Papers & Books===<br />
* ''Symplectic structure of the moduli space of sheaves on an abelian or K3 surface'' - Shigeru Mukai.<br />
<br />
* ''Residues and Duality'' - Robin Hatshorne.<br />
** Have you heard of Serre Duality? Would you like to really understand the nuts and bolts of it and its generalizations? If so this book is for you. (You wouldn't need to read the whole book to give a talk ;).)<br />
<br />
* ''Coherent sheaves on P^n and problems in linear algebra'' - A. A. Beilinson.<br />
** In this two page paper constructs the semi-orthogonal decomposition of the derived category of coherent sheaves on projective space. (This topic is very important, and there are a ton of other resources for this result and the general theory of derived categories.)<br />
<br />
* ''Frobenius splitting and cohomology vanishing for Schubert varieties'' - V.B. Mehta and A. Ramanathan.<br />
** In characteristic p the fact that (x+y)^p=x^p+y^p means that one has the Frobenius morphism, which sends f to f^p. In this paper the authors introduce the notion of what it means for a variety to be Frobenius split, and use this to prove certain cohomologcal vanishing results for Schubert varieties. Since then Frobenius splitting -- and its related cousins (F-regularity, strong F-regularity, F-purity, etc.) have played large roles in geometry and algebra in characteristic p. This is a good place to get a sense for what kicked all this stuff off! <br />
<br />
* ''Schubert Calculus'' - S. L. Kleiman and Dan Laksov.<br />
** An introduction to Schubert calculus suitable for those of all ages. I am told the paper essentially only uses linear algebra!<br />
<br />
* ''Rational Isogenies of Prime Degree'' - Barry Mazur.<br />
** In this paper Mazur classifies all isogenies of rational elliptic curves of prime order. As a result of this he deduces his famous result that the torsion subgroup of an elliptic curve (over Q) is one of 15 abelian groups. This definitely stares into the land of number theory, but certainly would still be of interest to many.<br />
<br />
* ''Esquisse d’une programme'' - Alexander Grothendieck.<br />
** Originating from a grant proposal in the mid 1980's this famous paper outlines a tantalizing research program, which seeks to tie numerous different areas of math (algebraic geometry, Teichmuller theory, Galois theory, etc.) together. This is where Grothendieck introduced his famous Lego game and dessin d'enfant. While just a research proposal this paper has seemingly inspired a ton of cool math, and will allow you to "blow peoples’ minds". (The original paper is in French, but there are English translations out there.)<br />
<br />
* ''Géométrie algébraique et géométrie analytique'' - J.P. Serre.<br />
** A projective variety X over the complex numbers has two lives, an algebraic and an analytic, depending on which topology one wishes to work with. That is one can think about X as a complex manifold and work with holomorphic functions or as an algebraic variety and work with regular functions. Hence to any complex projective variety we have two sheaf theories and as a result two cohomology theories. In this famous paper Serre compares these two and shows they are in fact the same. (''Note: This is a super fundamental result that is used all the time; normally in the following way: Uhh... What do you mean by cohomology? Well by GAGA or something it doesn't really mater.) (The original paper is in French, but there are English translations out there.)<br />
<br />
* ''Limit linear series: Basic theory''- David Eisenbud and Joe Harris.<br />
** One of the more profitable tools -- especially when studying moduli spaces -- in a geometers tool box is the theory of degenerations. However, sometimes we care about more than just the variety we are degenerating and want to keep track of things like vector/line bundles. In this paper Eisenbud and Harris develop the theory of degenerating a curve together with a linear series. From this they prove a ton of cool results: M_g is of general type for g>24, Brill-Noether theory, etc.<br />
<br />
* ''Picard Groups of Moduli Problems'' - David Mumford.<br />
** This paper is essentially the origin of algebraic stacks.<br />
<br />
* ''The Structure of Algebraic Threefolds: An Introduction to Mori's Program'' - Janos Kollar<br />
** This paper is an introduction to Mori's famous ``minimal model'' program, which is a far reaching program seeking to understand the birational geometry of higher dimensional varieties. <br />
<br />
* ''Cayley-Bacharach Formulas'' - Qingchun Ren, Jürgen Richter-Gebert, Bernd Sturmfels.<br />
** A classical result we all learn in a first semester of algebraic geometry is that 5 points in the plane (in general position) determine a unique plane conic. One can similarly show that 9 (general) points in the plane determine a unique plane cubic curve. This paper tries to answer the question: ``What is equation for this cubic curve?''.<br />
<br />
* ''On Varieties of Minimal Degree (A Centennial Approach)'' - David Eisenbud and Joe Harris.<br />
** Suppose X is a projective variety embedded in projective space so that X is not contained in any hyperplane. By projecting from general points one can see that the degree of X is at least codim(X)+1. This paper discusses the classification of varieties that achieve this lower degree bound i.e. varieties of minimal degree. This topic is quite classical and the paper seems to contain a nice mixture of classical and modern geometry.<br />
<br />
* ''The Gromov-Witten potential associated to a TCFT'' - Kevin J. Costello.<br />
** This seems incredibly interesting, but fairing warning this paper has been described as ''highly technical'', which considering it uses A-infinity algebras and the derived category of a Calabi-Yau seems like a reasonable description. (This paper may be covered in Caldararu's Spring 2017 topics course.)<br />
__NOTOC__<br />
<br />
== Spring 2017 ==<br />
<br />
<center><br />
{| style="color:black; font-size:120%" border="0" cellpadding="14" cellspacing="5"<br />
|-<br />
| bgcolor="#D0D0D0" width="300" align="center"|'''Date'''<br />
| bgcolor="#A6B658" width="300" align="center"|'''Speaker'''<br />
| bgcolor="#BCD2EE" width="300" align="center"|'''Title (click to see abstract)'''<br />
|-<br />
| bgcolor="#E0E0E0"| February 14<br />
| bgcolor="#C6D46E"| Moisés Herradón Cueto<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#February 14| Fun with commutative groups]]<br />
|-<br />
| bgcolor="#E0E0E0"| February 21<br />
| bgcolor="#C6D46E"| Moisés Herradón Cueto<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#February 21| <math>\mathcal F</math>un with commutative groups]]<br />
|-<br />
| bgcolor="#E0E0E0"| February 28<br />
| bgcolor="#C6D46E"| Dima Arinkin<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#February 28| ODEs: algebraic vs analytic vs formal]]<br />
|-<br />
| bgcolor="#E0E0E0"| March 7<br />
| bgcolor="#C6D46E"| Vladimir Sotirov<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#March 7| Topology of Affine Schemes]]<br />
|-<br />
| bgcolor="#E0E0E0"| March 14<br />
| bgcolor="#C6D46E"| David Wagner<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#March 14| Derived Quot Schemes]]<br />
|-<br />
| bgcolor="#E0E0E0"| March 21<br />
| bgcolor="#C6D46E"| Mao Li<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#March 21| D modules in prime characteristic]]<br />
|-<br />
| bgcolor="#E0E0E0"| March 28<br />
| bgcolor="#C6D46E"| Spring break<br />
| bgcolor="#BCE2FE"| Whoo!<br />
|-<br />
| bgcolor="#E0E0E0"| April 4<br />
| bgcolor="#C6D46E"| Rachel Davis<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#April 4| TBD]]<br />
|-<br />
| bgcolor="#E0E0E0"| April 11<br />
| bgcolor="#C6D46E"| Brandon Boggess<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#April 11| TBD]]<br />
|-<br />
| bgcolor="#E0E0E0"| April 18<br />
| bgcolor="#C6D46E"| Soumya Sankar<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#April 18| TBD]]<br />
|-<br />
| bgcolor="#E0E0E0"| April 25<br />
| bgcolor="#C6D46E"| Solly Parenti<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#April 25| TBD]]<br />
|-<br />
| bgcolor="#E0E0E0"| May 2<br />
| bgcolor="#C6D46E"| Mao Li<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#May 2| TBD]]<br />
|}<br />
</center><br />
<br />
== February 14 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''Moisés Herradón Cueto'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: Fun with commutative groups<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
My goal is to next week talk about Gerard Laumon's preprint ''Transformation de Fourier généralisée'', which will encapsulate all the Fourier transforms I can name (which for me includes the Fourier transform for D-modules on affine space, the Mellin transform, the Fourier-Mukai transform for abelian varieties and the rare John Mahoney transform between modules on the punctured line and vector spaces with a Z-action) into one crazy package.<br />
<br />
In order to achieve this altered mental state, we will have to rethink all our preconceptions, and rediscover algebraic groups, make sense of Cartier duality for them, define formal groups along the way, and see how duality of Abelian varieties relates to Cartier duality. If you come to the talk in an already in this altered mental state, then hopefully I'll do some examples that you've been too lazy to work out for yourself.<br />
<br />
|} <br />
</center><br />
<br />
== February 21 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''<math>\mathcal F</math>un with commutative groups'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: <math>\mathcal F</math>un with commutative groups<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
I will talk about how last week's Cartier duality relates to duality for abelian varieties. Then we will see how this allows us to take certain complexes of groups which are self dual, going back to altered mental states which are now derived.<br />
<br />
If we're going to Fourier transform something, it should be a sheaf, but what is even a sheaf on a complex of groups? Once we see what it should be, I will handwave what the Fourier transform is and give a bunch of concrete examples.<br />
<br />
|} <br />
</center><br />
<br />
== February 28 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''Dima Arinkin'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: ODEs: algebraic vs analytic vs formal<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
Linear ordinary differential equations (or, as they are known geometrically, bundles with connections on Riemann surfaces) can be studied from many directions. In algebraic geometry, the goal is ''to classify'' equations rather than ''to solve'' them. The classification can be<br />
done in different settings: algebraic, analytic, or formal; each setting has its advantages and disadvantages. However, for one of the most<br />
important class of equations (equations with regular singularities aka Fuchsian equations) the three approaches agree, leading to a rich <br />
and beautiful picture. <br />
<br />
In my talk, I will sketch the algebraic theory of differential equations, focusing on equations with regular singularities. (I do not expect to have time<br />
for irregular singularities.) The talk is related to my topics course on D-modules, but it does not rely on the topics course.<br />
|} <br />
</center><br />
<br />
== March 7 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''Vladimir Sotirov'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: Topology of Affine Schemes<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
I will explain in what sense flat morphisms of (affine) schemes are the correct analogue of open maps of topological spaces, and then use that to explain how surjectivity in the sense of Zariski spectra corresponds to surjectivity of functors of points.<br />
<br />
|} <br />
</center><br />
<br />
== March 14 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''David Wagner'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: Derived Quot Schemes<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
The titular paper of Ciocan-Fontanine & Kapranov constructs a "derived" version of Grothendieck's Quot scheme, whose degree zero truncation is the ordinary Quot scheme, and whose tangent space at each k-point consists higher Ext's. In this talk, we will talk about what is meant by "derived" in modern AG and why you might want a derived Quot scheme. In the remaining time, we will give a (hopefully transparent) description of how CF&K construct RQuot.<br />
<br />
|} <br />
</center><br />
<br />
== March 21 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''Mao Li'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: D-modules in prime characteristic<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
TBD<br />
<br />
|} <br />
</center><br />
<br />
== April 4 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''TBD'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: TBD<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
TBD<br />
<br />
|} <br />
</center><br />
<br />
== April 11 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''TBD'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: TBD<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
TBD<br />
<br />
|} <br />
</center><br />
<br />
== April 18 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''TBD'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: TBD<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
TBD<br />
<br />
|} <br />
</center><br />
<br />
== April 25 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''TBD'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: TBD<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
TBD<br />
<br />
|} <br />
</center><br />
<br />
== May 2 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''TBD'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: TBD<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
TBD<br />
<br />
|} <br />
</center><br />
<br />
<br />
== Organizers' Contact Info ==<br />
[http://www.math.wisc.edu/~juliettebruce Juliette Bruce]<br />
<br />
[http://www.math.wisc.edu/~clement Nathan Clement]<br />
<br />
[https://www.math.wisc.edu/~moises Moisés Herradón Cueto]<br />
<br />
== Past Semesters ==<br />
[https://www.math.wisc.edu/wiki/index.php/Graduate_Algebraic_Geometry_Seminar_Fall_2017 Fall 2017]<br />
<br />
[https://www.math.wisc.edu/wiki/index.php/Graduate_Algebraic_Geometry_Seminar_Spring_2017 Spring 2017]<br />
<br />
[https://www.math.wisc.edu/wiki/index.php/Graduate_Algebraic_Geometry_Seminar_Fall_2016 Fall 2016]<br />
<br />
[https://www.math.wisc.edu/wiki/index.php/Graduate_Algebraic_Geometry_Seminar_Spring_2016 Spring 2016]<br />
<br />
[https://www.math.wisc.edu/wiki/index.php/Graduate_Algebraic_Geometry_Seminar_(Fall_2015) Fall 2015]</div>Lmaohttps://hilbert.math.wisc.edu/wiki/index.php?title=Graduate_Algebraic_Geometry_Seminar_Spring_2018&diff=15217Graduate Algebraic Geometry Seminar Spring 20182018-03-09T14:49:08Z<p>Lmao: /* Spring 2017 */</p>
<hr />
<div>'''<br />
'''When:''' Wednesdays 3:40pm<br />
<br />
'''Where:'''Van Vleck B321 (Spring 2018)<br />
[[Image:cat.jpg|thumb|220px| | Lizzie the OFFICIAL mascot of GAGS!!]]<br />
<br />
'''Who:''' All undergraduate and graduate students interested in algebraic geometry, commutative algebra, and related fields are welcome to attend.<br />
<br />
'''Why:''' The purpose of this seminar is to learn algebraic geometry and commutative algebra by giving and listening to talks in a informal setting. Talks are typically accessible to beginning graduate students and take many different forms. Sometimes people present an interesting paper they find. Other times people give a prep talk for the Friday Algebraic Geometry Seminar. Other times people give a series of talks on a topic they have been studying in-depth. Regardless the goal of GAGS is to provide a supportive and inclusive place for all to learn more about algebraic geometry and commutative algebra.<br />
<br />
'''How:'''If you want to get emails regarding time, place, and talk topics ('''which are often assigned quite last minute''') add yourself to the gags mailing list: gags@lists.wisc.edu. The list registration page is [https://admin.lists.wisc.edu/index.php?p=11&l=gags here].<br />
'''<br />
<br />
== Give a talk! ==<br />
We need volunteers to give talks this semester. If you're interested contact [mailto:juliette.bruce@math.wisc.edu Juliette] or [mailto:moises@math.wisc.edu Moisés], or just add yourself to the list (though in that case we might move your talk later without your permission). Beginning graduate students are particularly encouraged to give a talk, since it's a great way to get your feet wet with the material.<br />
<br />
== Being an audience member ==<br />
The goal of GAGS is to create a safe and comfortable space inclusive of all who wish to expand their knowledge of algebraic geometry and commutative algebra. In order to promote such an environment in addition to the standard expectations of respect/kindness all participants are asked to following the following guidelines:<br />
* Do Not Speak For/Over the Speaker: <br />
* Ask Questions Appropriately: <br />
<br />
==The List of Topics that we Made February 2018==<br />
<br />
On February 21st of the Month of February of The 2018th Year of the Seventh Age of The Sun, the People Present at GAGS Compiled Ye Followinge Liste of Topics They Wished to Hear Aboute:<br />
<br />
Feel free to edit the list and/or add references to learn this stuff from.<br />
<br />
* Schubert Calculus, aka how many lines intersect four given lines in three-dimensional space? The answer to this question is prettiest when you think about it as a problem of intersecting subvarieties in the Grassmanian. ''What is the Grassmanian, you say?'' That's probably a talk we should have every year, so you should give it!<br />
<br />
* Kindergarten GAGA. GAGA stands for Algebraic Geometry - Analytic Geometry. Serre wrote a famous paper explaining how the two are related, and you could give an exposition suitable to kindergardeners.<br />
<br />
* Katz and Mazur explanation of what a modular form is. What is it?<br />
<br />
* Kindergarten moduli of curves.<br />
<br />
* What is a dualizing sheaf? What is a dualizing complex? What is Serre duality? What is local duality? Can local duality help us understand Serre duality?<br />
<br />
* Generalizations of Riemann - Roch. (Grothendieck - Riemann - Roch? Hirzebruch - Riemann - Roch?)<br />
<br />
* Hodge theory for babies<br />
<br />
* What is a Néron model?<br />
<br />
* What is a crystal? What does it have to do with D-modules? [http://www.math.harvard.edu/~gaitsgde/grad_2009/SeminarNotes/Nov17-19(Crystals).pdf Here's an encouragingly short set of notes on it].<br />
<br />
* What and why is a dessin d'enfants?<br />
<br />
* DG Schemes.<br />
<br />
<br />
==Ed Dewey's Wish List Of Olde==<br />
<br />
Back in the day Ed and Nathan made this list of topics they wanted to hear. They all sound super duper cool, but it's also true that they had many years of AG behind their backs, so this list might not be very representative of what the GAGS audience wants to hear bout.<br />
<br />
Here are the topics we're '''DYING''' to learn about! Please consider looking into one of these topics and giving one or two GAGS talks.<br />
<br />
===Specifically Vague Topics===<br />
* D-modules 101: basics of D-modules, equivalence between left and right D-modules, pullbacks, pushforwards, maybe the Gauss-Manin Connection. Claude Sabbah's introduction to the subject could be a good place to start.<br />
<br />
* Sheaf operations on D-modules (the point is that then you can get a Fourier-Mukai transform between certain O-modules and certain D-modules, which is more or less how geometric Langlands is supposed to work)<br />
<br />
===Famous Theorems===<br />
<br />
===Interesting Papers & Books===<br />
* ''Symplectic structure of the moduli space of sheaves on an abelian or K3 surface'' - Shigeru Mukai.<br />
<br />
* ''Residues and Duality'' - Robin Hatshorne.<br />
** Have you heard of Serre Duality? Would you like to really understand the nuts and bolts of it and its generalizations? If so this book is for you. (You wouldn't need to read the whole book to give a talk ;).)<br />
<br />
* ''Coherent sheaves on P^n and problems in linear algebra'' - A. A. Beilinson.<br />
** In this two page paper constructs the semi-orthogonal decomposition of the derived category of coherent sheaves on projective space. (This topic is very important, and there are a ton of other resources for this result and the general theory of derived categories.)<br />
<br />
* ''Frobenius splitting and cohomology vanishing for Schubert varieties'' - V.B. Mehta and A. Ramanathan.<br />
** In characteristic p the fact that (x+y)^p=x^p+y^p means that one has the Frobenius morphism, which sends f to f^p. In this paper the authors introduce the notion of what it means for a variety to be Frobenius split, and use this to prove certain cohomologcal vanishing results for Schubert varieties. Since then Frobenius splitting -- and its related cousins (F-regularity, strong F-regularity, F-purity, etc.) have played large roles in geometry and algebra in characteristic p. This is a good place to get a sense for what kicked all this stuff off! <br />
<br />
* ''Schubert Calculus'' - S. L. Kleiman and Dan Laksov.<br />
** An introduction to Schubert calculus suitable for those of all ages. I am told the paper essentially only uses linear algebra!<br />
<br />
* ''Rational Isogenies of Prime Degree'' - Barry Mazur.<br />
** In this paper Mazur classifies all isogenies of rational elliptic curves of prime order. As a result of this he deduces his famous result that the torsion subgroup of an elliptic curve (over Q) is one of 15 abelian groups. This definitely stares into the land of number theory, but certainly would still be of interest to many.<br />
<br />
* ''Esquisse d’une programme'' - Alexander Grothendieck.<br />
** Originating from a grant proposal in the mid 1980's this famous paper outlines a tantalizing research program, which seeks to tie numerous different areas of math (algebraic geometry, Teichmuller theory, Galois theory, etc.) together. This is where Grothendieck introduced his famous Lego game and dessin d'enfant. While just a research proposal this paper has seemingly inspired a ton of cool math, and will allow you to "blow peoples’ minds". (The original paper is in French, but there are English translations out there.)<br />
<br />
* ''Géométrie algébraique et géométrie analytique'' - J.P. Serre.<br />
** A projective variety X over the complex numbers has two lives, an algebraic and an analytic, depending on which topology one wishes to work with. That is one can think about X as a complex manifold and work with holomorphic functions or as an algebraic variety and work with regular functions. Hence to any complex projective variety we have two sheaf theories and as a result two cohomology theories. In this famous paper Serre compares these two and shows they are in fact the same. (''Note: This is a super fundamental result that is used all the time; normally in the following way: Uhh... What do you mean by cohomology? Well by GAGA or something it doesn't really mater.) (The original paper is in French, but there are English translations out there.)<br />
<br />
* ''Limit linear series: Basic theory''- David Eisenbud and Joe Harris.<br />
** One of the more profitable tools -- especially when studying moduli spaces -- in a geometers tool box is the theory of degenerations. However, sometimes we care about more than just the variety we are degenerating and want to keep track of things like vector/line bundles. In this paper Eisenbud and Harris develop the theory of degenerating a curve together with a linear series. From this they prove a ton of cool results: M_g is of general type for g>24, Brill-Noether theory, etc.<br />
<br />
* ''Picard Groups of Moduli Problems'' - David Mumford.<br />
** This paper is essentially the origin of algebraic stacks.<br />
<br />
* ''The Structure of Algebraic Threefolds: An Introduction to Mori's Program'' - Janos Kollar<br />
** This paper is an introduction to Mori's famous ``minimal model'' program, which is a far reaching program seeking to understand the birational geometry of higher dimensional varieties. <br />
<br />
* ''Cayley-Bacharach Formulas'' - Qingchun Ren, Jürgen Richter-Gebert, Bernd Sturmfels.<br />
** A classical result we all learn in a first semester of algebraic geometry is that 5 points in the plane (in general position) determine a unique plane conic. One can similarly show that 9 (general) points in the plane determine a unique plane cubic curve. This paper tries to answer the question: ``What is equation for this cubic curve?''.<br />
<br />
* ''On Varieties of Minimal Degree (A Centennial Approach)'' - David Eisenbud and Joe Harris.<br />
** Suppose X is a projective variety embedded in projective space so that X is not contained in any hyperplane. By projecting from general points one can see that the degree of X is at least codim(X)+1. This paper discusses the classification of varieties that achieve this lower degree bound i.e. varieties of minimal degree. This topic is quite classical and the paper seems to contain a nice mixture of classical and modern geometry.<br />
<br />
* ''The Gromov-Witten potential associated to a TCFT'' - Kevin J. Costello.<br />
** This seems incredibly interesting, but fairing warning this paper has been described as ''highly technical'', which considering it uses A-infinity algebras and the derived category of a Calabi-Yau seems like a reasonable description. (This paper may be covered in Caldararu's Spring 2017 topics course.)<br />
__NOTOC__<br />
<br />
== Spring 2017 ==<br />
<br />
<center><br />
{| style="color:black; font-size:120%" border="0" cellpadding="14" cellspacing="5"<br />
|-<br />
| bgcolor="#D0D0D0" width="300" align="center"|'''Date'''<br />
| bgcolor="#A6B658" width="300" align="center"|'''Speaker'''<br />
| bgcolor="#BCD2EE" width="300" align="center"|'''Title (click to see abstract)'''<br />
|-<br />
| bgcolor="#E0E0E0"| February 14<br />
| bgcolor="#C6D46E"| Moisés Herradón Cueto<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#February 14| Fun with commutative groups]]<br />
|-<br />
| bgcolor="#E0E0E0"| February 21<br />
| bgcolor="#C6D46E"| Moisés Herradón Cueto<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#February 21| <math>\mathcal F</math>un with commutative groups]]<br />
|-<br />
| bgcolor="#E0E0E0"| February 28<br />
| bgcolor="#C6D46E"| Dima Arinkin<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#February 28| ODEs: algebraic vs analytic vs formal]]<br />
|-<br />
| bgcolor="#E0E0E0"| March 7<br />
| bgcolor="#C6D46E"| Vladimir Sotirov<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#March 7| Topology of Affine Schemes]]<br />
|-<br />
| bgcolor="#E0E0E0"| March 14<br />
| bgcolor="#C6D46E"| David Wagner<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#March 14| TBD]]<br />
|-<br />
| bgcolor="#E0E0E0"| March 21<br />
| bgcolor="#C6D46E"| Mao Li<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#March 21| D modules in prime characteristic]]<br />
|-<br />
| bgcolor="#E0E0E0"| March 28<br />
| bgcolor="#C6D46E"| Spring break<br />
| bgcolor="#BCE2FE"| Whoo!<br />
|-<br />
| bgcolor="#E0E0E0"| April 4<br />
| bgcolor="#C6D46E"| Rachel Davis<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#April 4| TBD]]<br />
|-<br />
| bgcolor="#E0E0E0"| April 11<br />
| bgcolor="#C6D46E"| Brandon Boggess<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#April 11| TBD]]<br />
|-<br />
| bgcolor="#E0E0E0"| April 18<br />
| bgcolor="#C6D46E"| Soumya Sankar<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#April 18| TBD]]<br />
|-<br />
| bgcolor="#E0E0E0"| April 25<br />
| bgcolor="#C6D46E"| Solly Parenti<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#April 25| TBD]]<br />
|-<br />
| bgcolor="#E0E0E0"| May 2<br />
| bgcolor="#C6D46E"| TBD<br />
| bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#May 2| TBD]]<br />
|}<br />
</center><br />
<br />
== February 14 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''Moisés Herradón Cueto'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: Fun with commutative groups<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
My goal is to next week talk about Gerard Laumon's preprint ''Transformation de Fourier généralisée'', which will encapsulate all the Fourier transforms I can name (which for me includes the Fourier transform for D-modules on affine space, the Mellin transform, the Fourier-Mukai transform for abelian varieties and the rare John Mahoney transform between modules on the punctured line and vector spaces with a Z-action) into one crazy package.<br />
<br />
In order to achieve this altered mental state, we will have to rethink all our preconceptions, and rediscover algebraic groups, make sense of Cartier duality for them, define formal groups along the way, and see how duality of Abelian varieties relates to Cartier duality. If you come to the talk in an already in this altered mental state, then hopefully I'll do some examples that you've been too lazy to work out for yourself.<br />
<br />
|} <br />
</center><br />
<br />
== February 21 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''<math>\mathcal F</math>un with commutative groups'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: <math>\mathcal F</math>un with commutative groups<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
I will talk about how last week's Cartier duality relates to duality for abelian varieties. Then we will see how this allows us to take certain complexes of groups which are self dual, going back to altered mental states which are now derived.<br />
<br />
If we're going to Fourier transform something, it should be a sheaf, but what is even a sheaf on a complex of groups? Once we see what it should be, I will handwave what the Fourier transform is and give a bunch of concrete examples.<br />
<br />
|} <br />
</center><br />
<br />
== February 28 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''Dima Arinkin'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: ODEs: algebraic vs analytic vs formal<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
Linear ordinary differential equations (or, as they are known geometrically, bundles with connections on Riemann surfaces) can be studied from many directions. In algebraic geometry, the goal is ''to classify'' equations rather than ''to solve'' them. The classification can be<br />
done in different settings: algebraic, analytic, or formal; each setting has its advantages and disadvantages. However, for one of the most<br />
important class of equations (equations with regular singularities aka Fuchsian equations) the three approaches agree, leading to a rich <br />
and beautiful picture. <br />
<br />
In my talk, I will sketch the algebraic theory of differential equations, focusing on equations with regular singularities. (I do not expect to have time<br />
for irregular singularities.) The talk is related to my topics course on D-modules, but it does not rely on the topics course.<br />
|} <br />
</center><br />
<br />
== March 7 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''Vladimir Sotirov'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: Topology of Affine Schemes<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
I will explain in what sense flat morphisms of (affine) schemes are the correct analogue of open maps of topological spaces, and then use that to explain how surjectivity in the sense of Zariski spectra corresponds to surjectivity of functors of points.<br />
<br />
|} <br />
</center><br />
<br />
== March 14 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''TBD'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: TBD<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
TBD<br />
<br />
|} <br />
</center><br />
<br />
== March 21 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''TBD'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: TBD<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
TBD<br />
<br />
|} <br />
</center><br />
<br />
== April 4 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''TBD'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: TBD<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
TBD<br />
<br />
|} <br />
</center><br />
<br />
== April 11 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''TBD'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: TBD<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
TBD<br />
<br />
|} <br />
</center><br />
<br />
== April 18 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''TBD'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: TBD<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
TBD<br />
<br />
|} <br />
</center><br />
<br />
== April 25 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''TBD'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: TBD<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
TBD<br />
<br />
|} <br />
</center><br />
<br />
== May 2 ==<br />
<center><br />
{| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"<br />
|-<br />
| bgcolor="#A6B658" align="center" style="font-size:125%" | '''TBD'''<br />
|-<br />
| bgcolor="#BCD2EE" align="center" | Title: TBD<br />
|-<br />
| bgcolor="#BCD2EE" | <br />
Abstract: <br />
<br />
TBD<br />
<br />
|} <br />
</center><br />
<br />
<br />
== Organizers' Contact Info ==<br />
[http://www.math.wisc.edu/~juliettebruce Juliette Bruce]<br />
<br />
[http://www.math.wisc.edu/~clement Nathan Clement]<br />
<br />
[https://www.math.wisc.edu/~moises Moisés Herradón Cueto]<br />
<br />
== Past Semesters ==<br />
[https://www.math.wisc.edu/wiki/index.php/Graduate_Algebraic_Geometry_Seminar_Fall_2017 Fall 2017]<br />
<br />
[https://www.math.wisc.edu/wiki/index.php/Graduate_Algebraic_Geometry_Seminar_Spring_2017 Spring 2017]<br />
<br />
[https://www.math.wisc.edu/wiki/index.php/Graduate_Algebraic_Geometry_Seminar_Fall_2016 Fall 2016]<br />
<br />
[https://www.math.wisc.edu/wiki/index.php/Graduate_Algebraic_Geometry_Seminar_Spring_2016 Spring 2016]<br />
<br />
[https://www.math.wisc.edu/wiki/index.php/Graduate_Algebraic_Geometry_Seminar_(Fall_2015) Fall 2015]</div>Lmaohttps://hilbert.math.wisc.edu/wiki/index.php?title=Abelian_Varieties_2018&diff=14939Abelian Varieties 20182018-01-31T16:00:49Z<p>Lmao: </p>
<hr />
<div>== Overview ==<br />
This reading seminar will cover Kempf's "Complex Abelian Varieties and Theta Functions" book. Talks will be Mondays, 4:00-4:50 in Room B139.<br />
<br />
We can try to cover Chapters 1-7 and Chapter 11 and maybe some topics from the other chapters of Birkenhake and Lange's "Complex Abelian Varieties" as time permits.<br />
<br />
== Talk Schedule ==<br />
The following schedule might be adjusted as we go, depending on whether it seems too fast or not.<br />
<br />
Here is the [[https://www.math.wisc.edu/wiki/images/TOC.pdf Table of Contents]] of Kempf's book.<br />
<br />
{| cellpadding="8"<br />
!align="left" | date<br />
!align="left" | speaker<br />
!align="left" | sections<br />
<br />
|-<br />
|February 5<br />
|Rachel Davis<br />
|1.1-1.3<br />
|-<br />
|February 12<br />
|Soumya Sankar<br />
|1.4-1.5<br />
|-<br />
|February 19<br />
|Michael Brown<br />
|2.1-2.2<br />
|-<br />
|February 26<br />
|Solly Parenti<br />
|2.3-2.4<br />
|-<br />
|March 5<br />
|TBD<br />
|3.1-3.3<br />
|-<br />
|March 12<br />
|Moisés Herradón Cueto<br />
|3.4-3.6<br />
|-<br />
|March 19<br />
|TBD<br />
|4<br />
|-<br />
|March 26<br />
|No meeting<br />
|Spring Break<br />
|-<br />
|April 2<br />
|Mao Li<br />
|5.1-5.3<br />
|-<br />
|April 9<br />
|TBD<br />
|5.3-5.5<br />
|-<br />
|April 16<br />
|TBD<br />
|6<br />
|-<br />
|April 23<br />
|TBD<br />
|7<br />
|-<br />
|April 30<br />
|TBD<br />
|11<br />
|-<br />
|May 7<br />
|TBD<br />
|???<br />
|-<br />
|}</div>Lmaohttps://hilbert.math.wisc.edu/wiki/index.php?title=Algebraic_Geometry_Seminar_Fall_2017&diff=14450Algebraic Geometry Seminar Fall 20172017-10-26T12:38:12Z<p>Lmao: </p>
<hr />
<div>The seminar meets on Fridays at 2:25 pm in Van Vleck B321.<br />
<br />
Here is the schedule for [[Algebraic Geometry Seminar Spring 2017 | the previous semester]].<br />
<!--and for [[Algebraic Geometry Seminar Spring 2017 | the next semester]].---><br />
<!-- and for [[Algebraic Geometry Seminar | this semester]].---><br />
<br />
==Algebraic Geometry Mailing List==<br />
<br />
<br />
*Please join the [https://admin.lists.wisc.edu/index.php?p=11&l=ags AGS Mailing List] to hear about upcoming seminars, lunches, and other algebraic geometry events in the department (it is possible you must be on a math department computer to use this link).<br />
<br />
== Fall 2017 Schedule ==<br />
<br />
{| cellpadding="8"<br />
!align="left" | date<br />
!align="left" | speaker<br />
!align="left" | title<br />
!align="left" | host(s) <br />
<br />
|-<br />
|October 6<br />
|[http://www.math.wisc.edu/~mkbrown5// Michael Brown (UW-Madison)] <br />
|[[#Michael Brown|Topological K-theory of equivariant singularity categories]]<br />
|local<br />
<br />
|-<br />
|October 9 (Monday!!, 3:30-4:30, B119)<br />
|[http://www.math.utah.edu/~bertram/ Aaron Bertram (Utah)] <br />
|[[#Aaron Bertram|LePotier's Strange Duality and Quot Schemes]]<br />
|Andrei<br />
<br />
|-<br />
|October 27<br />
|Mao Li (UW-Madison) <br />
|[[#Mao Li|Poincare sheaf on the stack of rank two Higgs bundles]]<br />
|local<br />
<br />
|-<br />
|November 3<br />
|Dario Beraldo (Oxford) <br />
|[[#Dario Beraldo|tba]]<br />
|Dima<br />
<br />
|-<br />
|December 1<br />
|Jonathan Wang (IAS)<br />
|<br />
|Dima<br />
<br />
|-<br />
|December 8<br />
|[https://www.math.brown.edu/~mtchan/ Melody Chan (Brown))] <br />
|[[#Melody Chan|tba]]<br />
|Jordan<br />
|}<br />
<br />
== Abstracts ==<br />
<br />
===Michael Brown===<br />
<br />
'''Topological K-theory of equivariant singularity categories'''<br />
<br />
This is joint work with Tobias Dyckerhoff. Topological K-theory of complex-linear dg categories is a notion introduced by Blanc in his recent article "Topological K-theory of complex noncommutative spaces". In this talk, I will discuss a calculation of the topological K-theory of the dg category of graded matrix factorizations associated to a quasi-homogeneous polynomial with complex coefficients in terms of a classical topological invariant of a complex hypersurface singularity: the Milnor fiber and its monodromy.<br />
<br />
===Aaron Bertram===<br />
<br />
'''LePotier's Strange Duality and Quot Schemes'''<br />
Finite schemes of quotients over a smooth curve are a vehicle<br />
for proving strange duality for determinant line bundles on<br />
moduli spaces of vector bundles on Riemann surfaces. This was observed<br />
by Marian and Oprea. In work with Drew Johnson and Thomas Goller,<br />
we extend this idea to del Pezzo surfaces, where we are able to use it to prove cases of Le Potier's strange duality conjecture.<br />
<br />
===Mao Li===<br />
<br />
'''Poincare sheaf on the stack of rank two Higgs bundles'''<br />
It is well known that for a smooth projective curve, there exists a Poincare line bundle on the product of the Jacobian of the curve which is the universal family of topologically trivial line bundles of the Jacobian. It is natural to ask whether similar results still hold for the compactified Jacobian of singular curves. There has been a lot of work in this problem. In this talk I will sketch the construction of the Poincare sheaf for spectral curves in Hitchin fibration. The new feature is that we are able to extend the construction of Poincare sheaf to nonreduced spectral curves.</div>Lmaohttps://hilbert.math.wisc.edu/wiki/index.php?title=Algebraic_Geometry_Seminar_Fall_2017&diff=14449Algebraic Geometry Seminar Fall 20172017-10-25T23:56:37Z<p>Lmao: </p>
<hr />
<div>The seminar meets on Fridays at 2:25 pm in Van Vleck B321.<br />
<br />
Here is the schedule for [[Algebraic Geometry Seminar Spring 2017 | the previous semester]].<br />
<!--and for [[Algebraic Geometry Seminar Spring 2017 | the next semester]].---><br />
<!-- and for [[Algebraic Geometry Seminar | this semester]].---><br />
<br />
==Algebraic Geometry Mailing List==<br />
<br />
<br />
*Please join the [https://admin.lists.wisc.edu/index.php?p=11&l=ags AGS Mailing List] to hear about upcoming seminars, lunches, and other algebraic geometry events in the department (it is possible you must be on a math department computer to use this link).<br />
<br />
== Fall 2017 Schedule ==<br />
<br />
{| cellpadding="8"<br />
!align="left" | date<br />
!align="left" | speaker<br />
!align="left" | title<br />
!align="left" | host(s) <br />
<br />
|-<br />
|October 6<br />
|[http://www.math.wisc.edu/~mkbrown5// Michael Brown (UW-Madison)] <br />
|[[#Michael Brown|Topological K-theory of equivariant singularity categories]]<br />
|local<br />
<br />
|-<br />
|October 9 (Monday!!, 3:30-4:30, B119)<br />
|[http://www.math.utah.edu/~bertram/ Aaron Bertram (Utah)] <br />
|[[#Aaron Bertram|LePotier's Strange Duality and Quot Schemes]]<br />
|Andrei<br />
<br />
|-<br />
|October 27<br />
|Mao Li (UW-Madison) <br />
|[[#Mao Li|Poincare sheaf on the stack of rank two Higgs bundles]]<br />
|local<br />
<br />
|-<br />
|November 3<br />
|Dario Beraldo (Oxford) <br />
|[[#Dario Beraldo|tba]]<br />
|Dima<br />
<br />
|-<br />
|December 1<br />
|Jonathan Wang (IAS)<br />
|<br />
|Dima<br />
<br />
|-<br />
|December 8<br />
|[https://www.math.brown.edu/~mtchan/ Melody Chan (Brown))] <br />
|[[#Melody Chan|tba]]<br />
|Jordan<br />
|}<br />
<br />
== Abstracts ==<br />
<br />
===Michael Brown===<br />
<br />
'''Topological K-theory of equivariant singularity categories'''<br />
<br />
This is joint work with Tobias Dyckerhoff. Topological K-theory of complex-linear dg categories is a notion introduced by Blanc in his recent article "Topological K-theory of complex noncommutative spaces". In this talk, I will discuss a calculation of the topological K-theory of the dg category of graded matrix factorizations associated to a quasi-homogeneous polynomial with complex coefficients in terms of a classical topological invariant of a complex hypersurface singularity: the Milnor fiber and its monodromy.<br />
<br />
===Aaron Bertram===<br />
<br />
'''LePotier's Strange Duality and Quot Schemes'''<br />
Finite schemes of quotients over a smooth curve are a vehicle<br />
for proving strange duality for determinant line bundles on<br />
moduli spaces of vector bundles on Riemann surfaces. This was observed<br />
by Marian and Oprea. In work with Drew Johnson and Thomas Goller,<br />
we extend this idea to del Pezzo surfaces, where we are able to use it to prove cases of Le Potier's strange duality conjecture.<br />
<br />
===Mao Li===<br />
<br />
'''Poincare sheaf on the stack of rank two Higgs bundles'''<br />
It is well known that for a smooth projective curve, there exists a Poincare line bundle on the product of the Jacobian of the curve which is the universal family of topologically trivial line bundles of the Jacobian. It is natural to ask whether similar results still holds for the compactified Jacobian of singular curves. There has been a lots of work in this problem. In this talk I will sketch the construction of the Poincare sheaf for spectral curves in Hitchin fibration. The new feather is that we are able to extend the construction of Poincare sheaf to nonreduced spectral curves.</div>Lmaohttps://hilbert.math.wisc.edu/wiki/index.php?title=Algebraic_Geometry_Seminar_Fall_2017&diff=14373Algebraic Geometry Seminar Fall 20172017-10-16T17:18:01Z<p>Lmao: </p>
<hr />
<div>The seminar meets on Fridays at 2:25 pm in Van Vleck B321.<br />
<br />
Here is the schedule for [[Algebraic Geometry Seminar Spring 2017 | the previous semester]].<br />
<!--and for [[Algebraic Geometry Seminar Spring 2017 | the next semester]].---><br />
<!-- and for [[Algebraic Geometry Seminar | this semester]].---><br />
<br />
==Algebraic Geometry Mailing List==<br />
<br />
<br />
*Please join the [https://admin.lists.wisc.edu/index.php?p=11&l=ags AGS Mailing List] to hear about upcoming seminars, lunches, and other algebraic geometry events in the department (it is possible you must be on a math department computer to use this link).<br />
<br />
== Fall 2017 Schedule ==<br />
<br />
{| cellpadding="8"<br />
!align="left" | date<br />
!align="left" | speaker<br />
!align="left" | title<br />
!align="left" | host(s) <br />
<br />
|-<br />
|October 6<br />
|[http://www.math.wisc.edu/~mkbrown5// Michael Brown (UW-Madison)] <br />
|[[#Michael Brown|Topological K-theory of equivariant singularity categories]]<br />
|local<br />
<br />
|-<br />
|October 9 (Monday!!, 3:30-4:30, B119)<br />
|[http://www.math.utah.edu/~bertram/ Aaron Bertram (Utah)] <br />
|[[#Aaron Bertram|LePotier's Strange Duality and Quot Schemes]]<br />
|Andrei<br />
<br />
|-<br />
|October 27<br />
|Mao Li (UW-Madison) <br />
|[[#Mao Li|Poincare sheaf on the stack of rank two Higgs bundles]]<br />
|local<br />
<br />
|-<br />
|November 3<br />
|Dario Beraldo (Oxford) <br />
|[[#Dario Beraldo|tba]]<br />
|Dima<br />
<br />
|-<br />
|December 1st<br />
|[http://www.math.wisc.edu/~juliettebruce/ Juliette Bruce (UW-Madison)] <br />
|[[#Juliette Bruce |tba]]<br />
|local<br />
<br />
|-<br />
|December 8<br />
|[https://www.math.brown.edu/~mtchan/ Melody Chan (Brown))] <br />
|[[#Melody Chan|tba]]<br />
|Jordan<br />
|}<br />
<br />
== Abstracts ==<br />
<br />
===Michael Brown===<br />
<br />
'''Topological K-theory of equivariant singularity categories'''<br />
<br />
This is joint work with Tobias Dyckerhoff. Topological K-theory of complex-linear dg categories is a notion introduced by Blanc in his recent article "Topological K-theory of complex noncommutative spaces". In this talk, I will discuss a calculation of the topological K-theory of the dg category of graded matrix factorizations associated to a quasi-homogeneous polynomial with complex coefficients in terms of a classical topological invariant of a complex hypersurface singularity: the Milnor fiber and its monodromy.<br />
<br />
===Aaron Bertram===<br />
<br />
'''LePotier's Strange Duality and Quot Schemes'''<br />
Finite schemes of quotients over a smooth curve are a vehicle<br />
for proving strange duality for determinant line bundles on<br />
moduli spaces of vector bundles on Riemann surfaces. This was observed<br />
by Marian and Oprea. In work with Drew Johnson and Thomas Goller,<br />
we extend this idea to del Pezzo surfaces, where we are able to use it to prove cases of Le Potier's strange duality conjecture.</div>Lmaohttps://hilbert.math.wisc.edu/wiki/index.php?title=Algebraic_Geometry_Seminar_Fall_2017&diff=14369Algebraic Geometry Seminar Fall 20172017-10-15T01:14:00Z<p>Lmao: </p>
<hr />
<div>The seminar meets on Fridays at 2:25 pm in Van Vleck B321.<br />
<br />
Here is the schedule for [[Algebraic Geometry Seminar Spring 2017 | the previous semester]].<br />
<!--and for [[Algebraic Geometry Seminar Spring 2017 | the next semester]].---><br />
<!-- and for [[Algebraic Geometry Seminar | this semester]].---><br />
<br />
==Algebraic Geometry Mailing List==<br />
<br />
<br />
*Please join the [https://admin.lists.wisc.edu/index.php?p=11&l=ags AGS Mailing List] to hear about upcoming seminars, lunches, and other algebraic geometry events in the department (it is possible you must be on a math department computer to use this link).<br />
<br />
== Fall 2017 Schedule ==<br />
<br />
{| cellpadding="8"<br />
!align="left" | date<br />
!align="left" | speaker<br />
!align="left" | title<br />
!align="left" | host(s) <br />
<br />
|-<br />
|October 6<br />
|[http://www.math.wisc.edu/~mkbrown5// Michael Brown (UW-Madison)] <br />
|[[#Michael Brown|Topological K-theory of equivariant singularity categories]]<br />
|local<br />
<br />
|-<br />
|October 9 (Monday!!, 3:30-4:30, B119)<br />
|[http://www.math.utah.edu/~bertram/ Aaron Bertram (Utah)] <br />
|[[#Aaron Bertram|LePotier's Strange Duality and Quot Schemes]]<br />
|Andrei<br />
<br />
|-<br />
|October 27<br />
|Dario Beraldo (Oxford) <br />
|[[#Dario Beraldo|tba]]<br />
|Dima<br />
<br />
|-<br />
|November 3<br />
|Mao Li (UW-Madison) <br />
|[[#Mao Li|Poincare sheaves on the stack of rank two Higgs bundles]]<br />
|local<br />
<br />
|-<br />
|December 1st<br />
|[http://www.math.wisc.edu/~juliettebruce/ Juliette Bruce (UW-Madison)] <br />
|[[#Juliette Bruce |tba]]<br />
|local<br />
<br />
|-<br />
|December 8<br />
|[https://www.math.brown.edu/~mtchan/ Melody Chan (Brown))] <br />
|[[#Melody Chan|tba]]<br />
|Jordan<br />
|}<br />
<br />
== Abstracts ==<br />
<br />
===Michael Brown===<br />
<br />
'''Topological K-theory of equivariant singularity categories'''<br />
<br />
This is joint work with Tobias Dyckerhoff. Topological K-theory of complex-linear dg categories is a notion introduced by Blanc in his recent article "Topological K-theory of complex noncommutative spaces". In this talk, I will discuss a calculation of the topological K-theory of the dg category of graded matrix factorizations associated to a quasi-homogeneous polynomial with complex coefficients in terms of a classical topological invariant of a complex hypersurface singularity: the Milnor fiber and its monodromy.<br />
<br />
===Aaron Bertram===<br />
<br />
'''LePotier's Strange Duality and Quot Schemes'''<br />
Finite schemes of quotients over a smooth curve are a vehicle<br />
for proving strange duality for determinant line bundles on<br />
moduli spaces of vector bundles on Riemann surfaces. This was observed<br />
by Marian and Oprea. In work with Drew Johnson and Thomas Goller,<br />
we extend this idea to del Pezzo surfaces, where we are able to use it to prove cases of Le Potier's strange duality conjecture.</div>Lmao