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| | '''When? Where?:''' [https://wiki.math.wisc.edu/index.php/Graduate_Algebraic_Geometry_Seminar_Fall_2024 Link to current semester] |
| '''When:''' Thursday 5:00-6:00 PM CST | |
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| '''Where:''' https://uwmadison.zoom.us/j/92877740706?pwd=OVo0QmxRVEdUQ3RnUWpoWmFRRUI3dz09 | | '''Who:''' All undergraduate and graduate students interested in algebraic geometry, commutative algebra, and related fields are welcome to attend. |
| [[Image:cat.jpg|thumb|220px| | Lizzie the OFFICIAL mascot of GAGS!!]]
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| '''Who:''' All undergraduate and graduate students interested in algebraic geometry, commutative algebra, and related fields are welcome to attend. | | '''Why:''' The purpose of this seminar is to learn algebraic geometry and commutative algebra by giving and listening to talks in an informal setting. Sometimes people present an interesting paper they find. Other times people give a prep talk for the [https://hilbert.math.wisc.edu/wiki/index.php?title=Algebra_and_Algebraic_Geometry_Seminar&redirect=yes Algebraic Geometry Seminar] or present techniques motivated by the [[Applied Algebra Seminar|Applied Algebra 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. |
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| '''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. | | '''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@g-groups.wisc.edu by sending an email to gags+subscribe@g-groups.wisc.edu. If you prefer (and are logged in under your wisc google account) the list registration page is [https://groups.google.com/u/2/a/g-groups.wisc.edu/g/gags here]. |
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| '''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]. | | ''' Current Organizers: ''' [https://sites.google.com/view/kevindao Kevin Dao], [https://people.math.wisc.edu/~yluo237/ Yu (Joey) Luo], and [https://sites.google.com/view/bmartinova/home Boyana Martinova]. |
| '''
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| == Give a talk! == | | == Give a talk! == |
| We need volunteers to give talks this semester. If you're interested contact [mailto:cwcrowley@wisc.edu Colin] or [mailto:drwagner@math.wisc.edu David], 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. | | We need volunteers to give talks this semester. If you're interested, follow the link above to the current semester. Beginning graduate students are particularly encouraged to give a talk, since it's a great way to get your feet wet with the material. |
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| == Being an audience member == | | == Being an audience member == |
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| * Ask Questions Appropriately: | | * Ask Questions Appropriately: |
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| == Spring 2021 == | | == New Wish List as of Fall 2024 == |
| | | This wishlist is based on requests from graduate students (new and old). Don't be intimidated by the list (especially as a new graduate student), a lot of the topics here are advanced. You are always welcome to give a talk on a topic that does not appear on this list. If you are looking for a topic and none of the ones listed below sound compelling to you, you can always reach out to one of the organizers for more ideas! |
| <center>
| | *Topics in Representation Theory. There are many topics one can discussion: explaining Lie algebra representations via Fulton-Harris's book (Lecture 7-9), Brauer theory, the Stone-von Neumann theorem, classification and determination of unitary representations, the Harish-Chandra isomorphism, Borel-Bott-Weil, historical results such as Frobenius determinants. Quiver representations are another topic; there is a well-written book by Ralf Schiffler you could look at for this topic. |
| {| style="color:black; font-size:120%" border="0" cellpadding="14" cellspacing="5"
| | *The Riemann-Roch Theorem, its generalizations: Grothendieck-Riemann-Roch, Hirzebruch-Riemann-Roch, and applications. |
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| | *GAGA Theorems and how to use them. Some ideas on important results to talk about can be found [https://en.wikipedia.org/wiki/Algebraic_geometry_and_analytic_geometry#Important_results here]. For some references to look at: the appendix in Hartshorne's Algebraic Geometry, Serre's original GAGA paper, and Neeman's book Algebraic and Analytic Geometry. |
| | bgcolor="#E0E0E0"| February 4
| | *Cohen-Macaulay rings and schemes and variants of this type. A useful topic for those working with "mild singularities". The standard reference for this stuff is the book by Brunz and Herzog, but Eisenbud's Commutative Algebra book also has a lot of things to say about CM rings. |
| | bgcolor="#C6D46E"| Asvin Gothandaraman
| | *Hodge Theory for the working Algebraic Geometer. What is the Hodge decomposition? What is the Hard Lefschetz Theorem? What is the statement of the Hodge conjecture? Dolbeault cohomology? |
| | bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#February 4| A Bertini type theorem via probability]]
| | * Algebraic Curves via Hartshorne Chapter IV. What can be said projective curves of degree d and genus g? How do (did) people study algebraic curves? What are the important facts about curves a working algebraic geometer should know? |
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| | *Algebraic Suraces via Hartshorne Chapter V and Beauville's Complex Algebraic Surfaces. What does the birational classification of complex algebraic surfaces look like? How ''should'' we classify objects? |
| | bgcolor="#E0E0E0"| February 25
| | *Vector Bundles on P^n. A good reference for this is "Vector Bundles on Complex Projective Spaces" by Christian Okonek. Interesting points of discussion could inclued any of: Horrock's Criterion for vector bundles, Beilinson's Theorem, splitting of uniform bundles of rank r<n, moduli of stable 2-bundles, constructions of vector bundles on P^n for low values of n, Serre's construction of rank 2 bundles, proof of the Grothendieck-Birkhoff Theorem, and etc. These are all very classical problems / theorems in algebraic geometry and a talk on these topics would make a great expository talk. |
| | bgcolor="#C6D46E"| Colin Crowley
| | *Basics of Moduli: functor of points, representable functors, moduli of curves M_g, moduli of Abelian varieties of dimension g, and why do we care? A reference is Harris and Morrison, but there is the now growing textbook by Jarod Alper titled "Stacks and Moduli". Lots of lots of examples are encouraged. |
| | bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#February 25| TBD]]
| | *What is a syzygy? Compute some minimal free resolutions and tell people about how syzygies can tell you a lot about a curve. The Geometry of Syzygies by David Eisenbud is also a good reference and introduction to this topic. |
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| | * Derived categories and the Fourier-Mukai Transform. Introduce derived categories and explain their importance in algebraic geometry e.g. through the Fourier-Mukai transform. The book "Fourier-Mukai Transforms in Algebraic Geometry" by Daniel Huybrechts is a good reference for this stuff, but there is also the notes by Andrei Căldăraru on the Arxiv which are more to the point. |
| | bgcolor="#E0E0E0"| March 11
| | * Introduction to Algebraic Stacks: there are a number of references for this e.g. Alper's notes on Moduli, "Algebraic Stacks" by Tomas L. Gomez, the original paper of Deligne and Mumford titled "The Irreducibility of the Space of Curves of Given Genus", Martin Olsson's book "Algebraic Spaces and Stacks", and so on. Examples would be strongly encouraged over technical details and Alper's notes and/or Gomez's article are the best for this. |
| | bgcolor="#C6D46E"| Roufan Jiang
| | *There are many many classes of varieties out there that people are interested -- pick one and it could very well be a talk on its own! Here are a few examples; abelian varieties, secant varieties, tangent varieties, Kazdan-Lutszig varieties, toric varieties, flag varieties, Fano varieties, Prym varieties, and beyond.__NOTOC__ |
| | bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#March 11| TBD]]
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| | bgcolor="#E0E0E0"| March 18
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| | bgcolor="#C6D46E"| Alex Hof
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| | bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#March 18| An Introduction to the Deformation Theory of Complete Intersection Singularities]]
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| | bgcolor="#E0E0E0"| March 25
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| | bgcolor="#C6D46E"| Chiahui (Wendy) Cheng
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| | bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#March 25| Explicit Bound on Collective Strength of Regular Sequences of Three Homogeneous Polynomials]]
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| | bgcolor="#E0E0E0"| April 1
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| | bgcolor="#C6D46E"| Erika Pirnes
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| | bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#April 1| Reconstruction conjecture in graph theory]]
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| | bgcolor="#E0E0E0"| April 8
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| | bgcolor="#C6D46E"| Caitlyn Booms
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| | bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#April 8| TBD]]
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| |}
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| </center>
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| | |
| == February 4 ==
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| <center>
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| {| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"
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| | bgcolor="#A6B658" align="center" style="font-size:125%" | '''Asvin Gothandaraman'''
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| |-
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| | bgcolor="#BCD2EE" align="center" | Title: A Bertini type theorem via probability
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| | bgcolor="#BCD2EE" | Abstract: I will prove that most hyperplane slices are irreducible over any field by reducing to finite fields and applying probabilistic arguments. The talk will be very elementary!
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| |}
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| </center>
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| == February 25 ==
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| <center>
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| {| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"
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| | bgcolor="#A6B658" align="center" style="font-size:125%" | '''Colin Crowley'''
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| |-
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| | bgcolor="#BCD2EE" align="center" | Title: TBD
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| |-
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| | bgcolor="#BCD2EE" | Abstract: TDB
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| |}
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| </center>
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| == March 11 ==
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| <center>
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| {| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"
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| |-
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| | bgcolor="#A6B658" align="center" style="font-size:125%" | '''Roufan Jiang'''
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| |-
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| | bgcolor="#BCD2EE" align="center" | Title: TBD
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| |-
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| | bgcolor="#BCD2EE" | Abstract: TBD
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| |}
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| </center>
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| == March 18 ==
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| <center>
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| {| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"
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| |-
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| | bgcolor="#A6B658" align="center" style="font-size:125%" | '''Alex Hof'''
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| |-
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| | bgcolor="#BCD2EE" align="center" | Title: An Introduction to the Deformation Theory of Complete Intersection Singularities
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| |-
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| | bgcolor="#BCD2EE" | Abstract: Essentially what it says in the title; I'll give a fairly laid-back overview of some of the basic definitions and results about deformations of complete intersection singularities, including the Kodaira-Spencer map and the existence of versal deformations in the isolated case. If time permits, I'll discuss Morsification of isolated singularities. Very little background will be assumed.
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| |}
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| </center>
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| == March 25 ==
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| <center>
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| {| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"
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| |-
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| | bgcolor="#A6B658" align="center" style="font-size:125%" | '''Chiahui (Wendy) Cheng'''
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| |-
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| | bgcolor="#BCD2EE" align="center" | Title: Explicit Bound on Collective Strength of Regular Sequences of Three Homogeneous Polynomials
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| |-
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| | bgcolor="#BCD2EE" | Abstract: Let f_1,...,f_r in k[x_1,...,x_n] be homogeneous polynomial of degree d. Ananyan and Hochster (2016) proved that there exists a bound N=N(r,d) where if collective strength of f_1,...,f_r is greater than or equal to N, then f_1,...,f_r are regular sequence. In this paper, we study the explicit bound N(r,d) when $r=3$ and d=2,3 and show that N(3,2)=2 and N(3,3)>2.
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| |}
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| </center>
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| == April 1 ==
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| <center>
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| {| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"
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| | bgcolor="#A6B658" align="center" style="font-size:125%" | '''Erika Pirnes'''
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| |-
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| | bgcolor="#BCD2EE" align="center" | Title: Reconstruction conjecture in graph theory (Note: special time at noon!)
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| | bgcolor="#BCD2EE" | Abstract: The deck of a graph with n vertices is a multiset of n unlabeled graphs, each obtained from the original graph by deleting a vertex (and the edges incident to it). The reconstruction conjecture says that if two finite simple graphs with at least three vertices have the same deck, then they are isomorphic. The talk is going to focus on examples, and does not assume previous knowledge about graph theory.
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| |}
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| </center>
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| == April 8 ==
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| <center>
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| {| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"
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| | bgcolor="#A6B658" align="center" style="font-size:125%" | '''Caitlyn Booms'''
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| |-
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| | bgcolor="#BCD2EE" align="center" | Title: TBD
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| |-
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| | bgcolor="#BCD2EE" | Abstract: TBD
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| |}
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| </center>
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| | |
| | |
| == Fall 2020 ==
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| <center>
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| {| style="color:black; font-size:120%" border="0" cellpadding="14" cellspacing="5"
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| |-
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| | bgcolor="#E0E0E0"| September 30
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| | bgcolor="#C6D46E"| Asvin Gothandaraman
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| | bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#September 30| Title]]
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| |-
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| | bgcolor="#E0E0E0"| October 5
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| | bgcolor="#C6D46E"| Yifan Wei
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| | bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#October 5| On the Analytic Side (GAGA)]]
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| |-
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| | bgcolor="#E0E0E0"| October 14
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| | bgcolor="#C6D46E"| Owen Goff
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| | bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#October 14| The Magic and Comagic of Hopf Algebras]]
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| |-
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| | bgcolor="#E0E0E0"| October 21
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| | bgcolor="#C6D46E"| Roufan Jiang
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| | bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#October 21| TBD]]
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| |-
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| | bgcolor="#E0E0E0"| October 28
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| | bgcolor="#C6D46E"| Erika Pirnes
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| | bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#October 28| Introduction to representation theory via an example]]
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| |-
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| | bgcolor="#E0E0E0"| November 4
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| | bgcolor="#C6D46E"| Alex Mine
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| | bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#November 4| The Internal Language of the Category of Sheaves]]
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| |-
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| | bgcolor="#E0E0E0"| November 11
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| | bgcolor="#C6D46E"| John Cobb
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| | bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#November 11| Introduction to Boij-Söderberg Theory]]
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| |-
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| | bgcolor="#E0E0E0"| November 18
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| | bgcolor="#C6D46E"| Yunfan He
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| | bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#November 18| Introduction to mixed Hodge structure]]
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| |-
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| | bgcolor="#E0E0E0"| November November 25
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| | bgcolor="#C6D46E"| Maya Banks
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| | bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#November 25| TBD]]
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| |-
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| | bgcolor="#E0E0E0"| December 2
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| | bgcolor="#C6D46E"| Peter Wei
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| | bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#December 2| K3 Surfaces and Their Moduli]]
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| |-
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| | bgcolor="#E0E0E0"| December 9
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| | bgcolor="#C6D46E"| Wendy Cheng
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| | bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#December 9| TBD]]
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| |-
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| | bgcolor="#E0E0E0"| December 16
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| | bgcolor="#C6D46E"| Caitlyn Booms
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| | bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#December 16| Characteristic Dependence of Syzygies of Random Monomial Ideals]]
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| |}
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| </center>
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| | |
| == Spring 2020 ==
| |
| | |
| <center>
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| {| style="color:black; font-size:120%" border="0" cellpadding="14" cellspacing="5"
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| | bgcolor="#D0D0D0" width="300" align="center"|'''Date'''
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| | bgcolor="#A6B658" width="300" align="center"|'''Speaker'''
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| | bgcolor="#BCD2EE" width="300" align="center"|'''Title (click to see abstract)'''
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| | bgcolor="#E0E0E0"| January 29
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| | bgcolor="#C6D46E"| Colin Crowley
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| | bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#January 29| Lefschetz hyperplane section theorem via Morse theory]]
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| |-
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| | bgcolor="#E0E0E0"| February 5
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| | bgcolor="#C6D46E"| Asvin Gothandaraman
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| | bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#February 5| An Introduction to Unirationality]]
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| |-
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| | bgcolor="#E0E0E0"| February 12
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| | bgcolor="#C6D46E"| Qiao He
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| | bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#February 12| Title]]
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| |-
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| | bgcolor="#E0E0E0"| February 19
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| | bgcolor="#C6D46E"| Dima Arinkin
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| | bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#February 19| Blowing down, blowing up: surface geometry]]
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| |-
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| | bgcolor="#E0E0E0"| February 26
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| | bgcolor="#C6D46E"| Connor Simpson
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| | bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#February 26| Intro to toric varieties]]
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| |-
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| | bgcolor="#E0E0E0"| March 4
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| | bgcolor="#C6D46E"| Peter
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| | bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#March 4| An introduction to Grothendieck-Riemann-Roch Theorem]]
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| |-
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| | bgcolor="#E0E0E0"| March 11
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| | bgcolor="#C6D46E"| Caitlyn Booms
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| | bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#March 11| Intro to Stanley-Reisner Theory]]
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| |-
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| | bgcolor="#E0E0E0"| March 25
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| | bgcolor="#C6D46E"| Steven He
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| | bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#March 25| Braid group action on derived categories]]
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| | bgcolor="#E0E0E0"| April 1
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| | bgcolor="#C6D46E"| Vlad Sotirov
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| | bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#April 1| Title]]
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| |-
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| | bgcolor="#E0E0E0"| April 8
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| | bgcolor="#C6D46E"| Maya Banks
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| | bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#April 8| Title]]
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| |-
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| | bgcolor="#E0E0E0"| April 15
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| | bgcolor="#C6D46E"| Alex Hof
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| | bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#April 15| Embrace the Singularity: An Introduction to Stratified Morse Theory]]
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| | bgcolor="#E0E0E0"| April 22
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| | bgcolor="#C6D46E"| Ruofan
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| | bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#April 22| Birational geometry: existence of rational curves]]
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| | bgcolor="#E0E0E0"| April 29
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| | bgcolor="#C6D46E"| John Cobb
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| | bgcolor="#BCE2FE"|[[Graduate Algebraic Geometry Seminar#April 29| Title]]
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| |}
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| </center>
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| == January 29 ==
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| <center>
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| {| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"
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| |-
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| | bgcolor="#A6B658" align="center" style="font-size:125%" | '''Colin Crowley'''
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| |-
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| | bgcolor="#BCD2EE" align="center" | Title: Lefschetz hyperplane section theorem via Morse theory
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| | bgcolor="#BCD2EE" | Abstract: Morse theory allows you to learn about the topology of a manifold by studying the critical points of a nice function on the manifold. This perspective produces a nice proof of the theorem in the title, which concerns the homology of smooth projective varieties over C. I'll explain what the theorem says, say something about what Morse theory is and why it's related, and then finish with a neat example. I'm aiming to make this understandable to someone who's taken algebraic geometry 1 and topology 1.
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| |}
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| </center>
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| == February 5 ==
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| <center>
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| {| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"
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| | bgcolor="#A6B658" align="center" style="font-size:125%" | '''Asvin Gothandaraman '''
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| | bgcolor="#BCD2EE" align="center" | Title: An introduction to unirationality
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| | bgcolor="#BCD2EE" | Abstract: I will introduce the notion of unirationality and show that cubic hypersurfaces are unirational (following Kollar). If time permits, I will also show that unirational varieties are simply connected.
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| |}
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| </center>
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| == February 12 ==
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| <center>
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| {| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"
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| | bgcolor="#A6B658" align="center" style="font-size:125%" | '''Qiao He'''
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| | bgcolor="#BCD2EE" align="center" | Title:
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| |-
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| | bgcolor="#BCD2EE" | Abstract:
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| |}
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| </center>
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| == February 19 ==
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| <center>
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| {| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"
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| | bgcolor="#A6B658" align="center" style="font-size:125%" | '''Dima Arinkin'''
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| | bgcolor="#BCD2EE" align="center" | Title: Blowing down, blowing up: surface geometry
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| | bgcolor="#BCD2EE" | Abstract:A big question in algebraic geometry is how much one can change a variety without affecting it `generically'. More precisely, if two varieties are birational, how far can they be from being isomorphic?
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| The question is trivial for (smooth projective) curves: they are birational if and only if they are isomorphic. In higher dimension, the
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| situation is much more interesting. The most fundamental operation are the `blowup', which is a kind of alteration of a variety within its birational isomorphism class, and its opposite, the blowdown.
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| In my talk, I will introduce blowups and discuss their properties. Then (time permitting) I would like to look deeper at the case
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| of surfaces, where the combination of blowups and intersection theory provides a complete and beautiful picture. (If we do get to this point, I won't assume any knowledge of intersection theory: to an extent, this talk is my excuse to introduce it.)
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| |}
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| </center>
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| == February 26 ==
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| <center>
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| {| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"
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| | bgcolor="#A6B658" align="center" style="font-size:125%" | '''Connor Simpson'''
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| |-
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| | bgcolor="#BCD2EE" align="center" | Title: Intro to Toric Varieties
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| | bgcolor="#BCD2EE" | Abstract: A brief introduction to toric varieties: how to build them, formulas for computing topological data, toric blow-ups, and more.
| |
| |}
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| </center>
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| == March 4 ==
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| <center>
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| {| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"
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| |-
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| | bgcolor="#A6B658" align="center" style="font-size:125%" | '''Peter Wei'''
| |
| |-
| |
| | bgcolor="#BCD2EE" align="center" | Title: An introduction to Grothendieck-Riemann-Roch Theorem
| |
| |-
| |
| | bgcolor="#BCD2EE" | Abstract: The classical Riemann-Roch theorem tells you about how topological (genus) and analytical (through line bundle) properties on compact Riemann surface (i.e. smooth projective curve) relate to each other. Moreover, this theorem can be generalized to any vector bundles (or coherent sheaves) over any smooth projective varieties. Eventually, Grothendieck “relativized” this theorem as a property of a morphism between two projective varieties. In this talk I will introduce basic notions to formulate this theorem. If time permitting, enough examples will be given appropriately.
| |
| |}
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| </center>
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| == March 11 ==
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| <center>
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| {| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"
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| |-
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| | bgcolor="#A6B658" align="center" style="font-size:125%" | '''Caitlyn Booms'''
| |
| |-
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| | bgcolor="#BCD2EE" align="center" | Title: Intro to Stanley-Reisner Theory
| |
| |-
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| | bgcolor="#BCD2EE" | Abstract: Stanley-Reisner theory gives a dictionary between combinatorial objects (simplicial complexes) and algebraic objects (Stanley-Reisner rings). In this talk, I will introduce the main objects of study in this theory, describe this dictionary with several examples, and discuss how Stanley-Reisner theory can help us investigate algebra-geometric questions.
| |
| |}
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| </center>
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| == March 25 ==
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| <center>
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| {| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"
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| |-
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| | bgcolor="#A6B658" align="center" style="font-size:125%" | '''Steven He'''
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| |-
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| | bgcolor="#BCD2EE" align="center" | Title: Braid group action on derived category
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| |-
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| | bgcolor="#BCD2EE" | Abstract: In this talk, I will define spherical object and A_m-configuration in derived category of coherent sheaves, and say a few words about the motivation coming from the homological mirror symmetry.
| |
| |}
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| </center>
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| == April 1 ==
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| <center>
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| {| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"
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| |-
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| | bgcolor="#A6B658" align="center" style="font-size:125%" | '''Vlad Sotirov'''
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| |-
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| | bgcolor="#BCD2EE" align="center" | Title:
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| |-
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| | bgcolor="#BCD2EE" | Abstract:
| |
| |}
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| </center>
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| | |
| == April 8 ==
| |
| <center>
| |
| {| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"
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| |-
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| | bgcolor="#A6B658" align="center" style="font-size:125%" | '''Maya Banks'''
| |
| |-
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| | bgcolor="#BCD2EE" align="center" | Title:
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| |-
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| | bgcolor="#BCD2EE" | Abstract:
| |
| |}
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| </center>
| |
| | |
| == April 15 ==
| |
| <center>
| |
| {| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"
| |
| |-
| |
| | bgcolor="#A6B658" align="center" style="font-size:125%" | '''Alex Hof'''
| |
| |-
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| | bgcolor="#BCD2EE" align="center" | Title: Embrace the Singularity: An Introduction to Stratified Morse Theory
| |
| |-
| |
| | bgcolor="#BCD2EE" | Abstract: Early on in the semester, Colin told us a bit about Morse
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| Theory, and how it lets us get a handle on the (classical) topology of
| |
| smooth complex varieties. As we all know, however, not everything in
| |
| life goes smoothly, and so too in algebraic geometry. Singular
| |
| varieties, when given the classical topology, are not manifolds, but
| |
| they can be described in terms of manifolds by means of something called
| |
| a Whitney stratification. This allows us to develop a version of Morse
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| Theory that applies to singular spaces (and also, with a bit of work, to
| |
| smooth spaces that fail to be nice in other ways, like non-compact
| |
| manifolds!), called Stratified Morse Theory. After going through the
| |
| appropriate definitions and briefly reviewing the results of classical
| |
| Morse Theory, we'll discuss the so-called Main Theorem of Stratified
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| Morse Theory and survey some of its consequences.
| |
| |}
| |
| </center>
| |
| | |
| == April 22 ==
| |
| <center>
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| {| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"
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| |-
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| | bgcolor="#A6B658" align="center" style="font-size:125%" | '''Ruofan'''
| |
| |-
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| | bgcolor="#BCD2EE" align="center" | Title: Birational geometry: existence of rational curves
| |
| |-
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| | bgcolor="#BCD2EE" | Abstract: Rational curves on a variety control its birational geometry. It thus is important to determine whether they exist. People didn’t know how to do this systematically, before Mori discovered a deformation lemma which detect their existence, and bound their degree if they exist. I will briefly introduce Mori’s insight.
| |
| |}
| |
| </center>
| |
| | |
| == April 29 ==
| |
| <center>
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| {| style="color:black; font-size:100%" table border="2" cellpadding="10" width="700" cellspacing="20"
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| |-
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| | bgcolor="#A6B658" align="center" style="font-size:125%" | '''John Cobb'''
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| |-
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| | bgcolor="#BCD2EE" align="center" | Title:
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| |-
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| | bgcolor="#BCD2EE" | Abstract:
| |
| |}
| |
| </center>
| |
| | |
| | |
| == Organizers' Contact Info ==
| |
| | |
| [https://sites.google.com/view/colincrowley/home Colin Crowley]
| |
| | |
| [http://www.math.wisc.edu/~drwagner/ David Wagner]
| |
| | |
| ==The List of Topics that we Made February 2018==
| |
| | |
| 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:
| |
| | |
| Feel free to edit the list and/or add references to learn this stuff from. Since then, we've succeeded in talking about some of these, which doesn't mean there shouldn't be another talk. Ask around or look at old semester's websites.
| |
| | |
| * 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!
| |
| | |
| * 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.
| |
| | |
| * Katz and Mazur explanation of what a modular form is. What is it?
| |
| | |
| * Kindergarten moduli of curves.
| |
| | |
| * 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?
| |
| | |
| * Generalizations of Riemann - Roch. (Grothendieck - Riemann - Roch? Hirzebruch - Riemann - Roch?)
| |
| | |
| * Hodge theory for babies
| |
| | |
| * What is a Néron model?
| |
| | |
| * 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].
| |
| | |
| * What and why is a dessin d'enfants?
| |
| | |
| * DG Schemes.
| |
| | |
| ==Ed Dewey's Wish List Of Olde==__NOTOC__
| |
| | |
| 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.
| |
| | |
| 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.
| |
| | |
| ===Specifically Vague Topics===
| |
| * 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.
| |
| | |
| * 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)
| |
| | |
| ===Interesting Papers & Books===
| |
| * ''Symplectic structure of the moduli space of sheaves on an abelian or K3 surface'' - Shigeru Mukai.
| |
| | |
| * ''Residues and Duality'' - Robin Hatshorne.
| |
| ** 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 ;).)
| |
|
| |
|
| * ''Coherent sheaves on P^n and problems in linear algebra'' - A. A. Beilinson.
| | === Wishlists from Days of Yore === |
| ** 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.)
| | Wishlists from past years can now be found [[Old GAGS Wish Lists|here]]. |
|
| |
|
| * ''Frobenius splitting and cohomology vanishing for Schubert varieties'' - V.B. Mehta and A. Ramanathan.
| | == Semesters == |
| ** 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!
| |
|
| |
|
| * ''Schubert Calculus'' - S. L. Kleiman and Dan Laksov.
| | [[Image:newcat.jpg|thumb|220px| Toby the OFFICIAL mascot emeritus of GAGS!!]] |
| ** An introduction to Schubert calculus suitable for those of all ages. I am told the paper essentially only uses linear algebra!
| |
|
| |
|
| * ''Rational Isogenies of Prime Degree'' - Barry Mazur.
| | [https://wiki.math.wisc.edu/index.php/Graduate_Algebraic_Geometry_Seminar_Fall_2024 Fall 2024] |
| ** 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.
| |
|
| |
|
| * ''Esquisse d’une programme'' - Alexander Grothendieck.
| | [https://wiki.math.wisc.edu/index.php/Graduate_Algebraic_Geometry_Seminar_Spring_2024 Spring 2024] |
| ** 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.)
| |
|
| |
|
| * ''Géométrie algébraique et géométrie analytique'' - J.P. Serre.
| | [https://wiki.math.wisc.edu/index.php/Graduate_Algebraic_Geometry_Seminar_Fall_2023 Fall 2023] |
| ** 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.)
| |
|
| |
|
| * ''Limit linear series: Basic theory''- David Eisenbud and Joe Harris.
| | [https://wiki.math.wisc.edu/index.php/Graduate_Algebraic_Geometry_Seminar_Spring_2023 Spring 2023] |
| ** 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.
| |
|
| |
|
| * ''Picard Groups of Moduli Problems'' - David Mumford.
| | [https://wiki.math.wisc.edu/index.php/Graduate_Algebraic_Geometry_Seminar_Fall_2022 Fall 2022] |
| ** This paper is essentially the origin of algebraic stacks.
| |
|
| |
|
| * ''The Structure of Algebraic Threefolds: An Introduction to Mori's Program'' - Janos Kollar
| | [https://hilbert.math.wisc.edu/wiki/index.php/Graduate_Algebraic_Geometry_Seminar_Spring_2022 Spring 2022] |
| ** 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.
| |
|
| |
|
| * ''Cayley-Bacharach Formulas'' - Qingchun Ren, Jürgen Richter-Gebert, Bernd Sturmfels.
| | [https://hilbert.math.wisc.edu/wiki/index.php?title=Graduate_Algebraic_Geometry_Seminar_Fall_2021 Fall 2021] |
| ** 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?''.
| |
|
| |
|
| * ''On Varieties of Minimal Degree (A Centennial Approach)'' - David Eisenbud and Joe Harris.
| | [https://hilbert.math.wisc.edu/wiki/index.php?title=Graduate_Algebraic_Geometry_Seminar_Spring_2021 Spring 2021] |
| ** 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.
| |
|
| |
|
| * ''The Gromov-Witten potential associated to a TCFT'' - Kevin J. Costello.
| | [https://hilbert.math.wisc.edu/wiki/index.php?title=Graduate_Algebraic_Geometry_Seminar_Fall_2020 Fall 2020] |
| ** 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.)
| |
|
| |
|
| | [https://hilbert.math.wisc.edu/wiki/index.php/Graduate_Algebraic_Geometry_Seminar_Spring_2020 Spring 2020] |
|
| |
|
| == Past Semesters ==
| |
| [https://www.math.wisc.edu/wiki/index.php/Graduate_Algebraic_Geometry_Seminar_Fall_2019 Fall 2019] | | [https://www.math.wisc.edu/wiki/index.php/Graduate_Algebraic_Geometry_Seminar_Fall_2019 Fall 2019] |
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|
