Seminars Sorted by Series

Joint IAS/PNI Seminar on ML and Neuroscience

Dec
03
2019

Joint IAS/PNI Seminar on ML and Neuroscience

A distributional code for value in dopamine-based reinforcement learning
Matthew Botvinick
3:00pm|Princeton Neuroscience Institute, Room A32

Twenty years ago, a link was discovered between the neurotransmitter dopamine and the computational framework of reinforcement learning. Since then, it has become well established that dopamine release reflects a reward prediction error, a surprise...

Jan
14
2020

Joint IAS/PNI Seminar on ML and Neuroscience

Compositional inductive biases in human function learning
Samuel J. Gershman
12:00pm|Dilworth Room

This talk presents evidence that humans learn complex functions by harnessing compositionality: complex structure is decomposed into simpler building blocks. I formalize this idea in the framework of Bayesian nonparametric regression using a grammar...

Feb
18
2020

Joint IAS/PNI Seminar on ML and Neuroscience

Compositional generalization in minds and machines
Brenden Lake
4:00pm|Princeton Neurosciences Institute: Room A32

People learn in fast and flexible ways that elude the best artificial neural networks. Once a person learns how to “dax,” they can effortlessly understand how to “dax twice” or “dax vigorously” thanks to their compositional skills. In this talk, we...

Joint IAS/Princeton Arithmetic Geometry Seminar

Feb
06
2023

Joint IAS/Princeton Arithmetic Geometry Seminar

Conditional Computability of Rational Points on Hyperbolic Curves
Levent Alpöge
4:30pm|Princeton University, Fine Hall 314

In this talk, I will specify a Turing machine T and prove the following about it. 1. On input C/K a smooth projective hyperbolic curve over a number field, if T halts, then its output is C(K). 2. The Hodge, Tate, and Fontaine-Mazur conjectures imply...

Feb
20
2023

Joint IAS/Princeton Arithmetic Geometry Seminar

Diffracting prismatic envelopes
Arthur Ogus
4:30pm|Princeton University, Fine Hall 314

Let X/k be a smooth scheme over a perfect field k of characteristic p > 0 and let W be the Witt ring of k. Inspired by Drinfeld’s “stacky” approach to prismatic cohomology, Bhatt, Lurie, and others have shown that a lifting of X/k to W induces a...

Mar
06
2023

Joint IAS/Princeton Arithmetic Geometry Seminar

p-adic analogue of Borel's theorem
Ananth Shankar
4:30pm|Princeton University, Fine Hall 314

Borel proved that any holomorphic map from an affine complex algebraic curve to a Shimura variety (with sufficient level structure) must be algebraic. We will discuss a p-adic analogue of this theorem. This is joint work with Abhishek Oswal and...

Apr
03
2023

Joint IAS/Princeton Arithmetic Geometry Seminar

Functions on the Commuting Scheme Via Langlands Duality
4:00pm|Princeton University, Fine Hall 314

I will explain how ideas from the (geometric) Langlands program help solve the following purely algebraic problem: describe the ring of conjugation-invariant functions on the scheme of commuting pairs in a complex reductive group. The answer was...

Oct
09
2023

Joint IAS/Princeton Arithmetic Geometry Seminar

Irregular Loci in the Emerton-Gee Stack for GL2
3:30pm|Simonyi Hall 101 and Remote Access

Let K be a finite extension of Qp. The Emerton-Gee stack for GL2 is a stack of etale (phi, Gamma)-modules of rank two. Its reduced part, X, is an algebraic stack of finite type over a finite field, and can be viewed as a moduli stack of two...

Oct
30
2023

Joint IAS/Princeton Arithmetic Geometry Seminar

Shimurian Generalizations of Truncated Barsotti-Tate Groups (after V. Drinfeld)
4:30pm|Princeton University, Fine Hall 314

In a recent article, Vladimir Drinfeld proposed (using prismatic F-gauges) new "Shimurian" analogs of the stack of n-truncated Barsotti-Tate groups. I will give an overview of Drinfeld’s work and the relation to the prismatic Dieudonné theory of...

Nov
06
2023

Joint IAS/Princeton Arithmetic Geometry Seminar

What is the K-theory of the Complex Numbers?
Dustin Clausen
4:30pm|Simonyi Hall 101 and Remote Access

I will explain what the question means and how to make it precise. Then I will give a conjectural answer. This is based on joint work with Peter Scholze.

Nov
20
2023

Joint IAS/Princeton Arithmetic Geometry Seminar

Algebraic K-theory of Rings of Continuous Functions
Ko Aoki
4:30pm|Simonyi Hall 101 and Remote Access

Recent interactions between condensed mathematics and K-theory have led us to revisit the topic of (nonconnective) algebraic K-theory of topological algebras. In this talk, among recent developments, I will focus on the ring of continuous functions...

Nov
27
2023

Joint IAS/Princeton Arithmetic Geometry Seminar

Duality for 𝑝-adic Proétale Cohomology of Stein Spaces
4:30pm|Princeton University, Fine Hall 314

I will discuss duality theorems for p-adic proétale cohomology of rigid analytic Stein spaces, in both arithmetic and geometric cases. This is based on a joint work with Pierre Colmez and Wieslawa Niziol.

Dec
04
2023

Joint IAS/Princeton Arithmetic Geometry Seminar

Mirror Symmetry and the Breuil-Mezard Conjecture
Tony Feng
4:30pm|Simonyi Hall 101 and Remote Access

The Breuil-Mezard Conjecture predicts the existence of hypothetical "Breuil-Mezard cycles" that should govern congruences between mod p automorphic forms on a reductive group G. Most of the progress thus far has been concentrated on the case G = GL...

Dec
11
2023

Joint IAS/Princeton Arithmetic Geometry Seminar

Spin Structures on Number Fields
4:30pm|Princeton University, Fine Hall 314

In topology, the choice of a spin structure on an oriented surface gives a quadratic refinement of the intersection form on mod 2 homology. There is a similar story about 3-manifolds. I will report on joint work (in progress) with Artane Siad where...

Jan
22
2024

Joint IAS/Princeton Arithmetic Geometry Seminar

Tangent Bundles in p-adic Geometry
3:30pm|Simonyi Hall 101 and Remote Access

Because of the existence of approximate p-power roots, a perfectoid algebra over Q_p admits no continuous derivations, and thus the natural Kahler tangent space of a perfectoid space over Q_p is identically zero. However, it turns out that many...

Jan
29
2024

Joint IAS/Princeton Arithmetic Geometry Seminar

Intermediate Extension in Arithmetic Statistics
Will Sawin
3:30pm|Fine 322, Princeton University

Davenport-Heilbronn and Bhargava counted cubic, quartic, and quintic fields by first counting a larger set of orbits in some prehomogenous vector space and then sieving out the orbits corresponding to fields. Several mathematicians have studied...

Feb
05
2024

Joint IAS/Princeton Arithmetic Geometry Seminar

Truncated (G,mu)-Displays and Conjectures of Drinfeld
Keerthi Madapusi
3:30pm|Fine 322, Princeton University

We report on proofs of some recent conjectures of Drinfeld on the algebraicity of formal stacks associated with minuscule cocharacters of smooth group schemes over Z_p. These stacks are constructed using the theory of syntomification as developed by...

Feb
19
2024

Joint IAS/Princeton Arithmetic Geometry Seminar

Witt-Differential Operators
Christopher Dodd
3:30pm|Simonyi Hall 101

We describe a new theory of sheaves of rings of differential operators on the Witt-vectors on a smooth scheme characteristic p. Roughly speaking, these sheaves are to the de Rham-Witt complex as the usual sheaf of differential operators is to the de...

Feb
26
2024

Joint IAS/Princeton Arithmetic Geometry Seminar

Prismatization and the Image of the J-homomorphism
3:30pm|Fine 322, Princeton University

For p a prime number, Bhatt–Lurie and Drinfeld defined the prismatization of a p-complete commutative ring R. I will overview a different perspective on prismatization, using homotopy theory and in particular topological Hochschild homology. This...

Mar
04
2024

Joint IAS/Princeton Arithmetic Geometry Seminar

Pro-Etale Cohomology of Rigid-Analytic Spaces
Johannes Anschütz
3:30pm|Simonyi Hall 101 and Remote Access

In this talk I want to explain some surprising features of the pro-etale cohomology of rigid-analytic varieties, and how they can be explained by a six functor formalism with values in solid quasi-coherent sheaves on the Fargues-Fontaine curve. 

This...

Mar
18
2024

Joint IAS/Princeton Arithmetic Geometry Seminar

Towards a Unified Theory of Canonical Heights on Abelian Varieties
Padmavathi Srinivasan
3:30pm|Simonyi Hall 101 and Remote Access

p-adic heights have been a rich source of explicit functions vanishing on rational points on a curve. In this talk, we will outline a new construction of canonical p-adic heights on abelian varieties from p-adic adelic metrics, using p-adic Arakelov...

Apr
01
2024

Joint IAS/Princeton Arithmetic Geometry Seminar

On De Rham Flip-Flopping in Dual Towers
3:30pm|Simonyi Hall 101 and Remote Access

We will discuss de Rham and Hyodo-Kato flip-flopping for dual towers of rigid analytic spaces. The main tools are comparison theorems expressing the two cohomologies as pro-étale cohomologies of corresponding relative period sheaves that, by...

Apr
08
2024

Joint IAS/Princeton Arithmetic Geometry Seminar

Recent Progress on Hodge Loci
Bruno Klingler
3:30pm|Fine 322, Princeton University

Given a quasi projective family S of complex algebraic varieties, its Hodge locus is the locus of points of S where the corresponding variety admits exceptional Hodge classes (conjecturally: exceptional algebraic cycles). In this talk, I will survey...

Apr
22
2024

Joint IAS/Princeton Arithmetic Geometry Seminar

Pointwise Good Reduction Criteria for Local Systems
Ziquan Yang
3:30pm|Fine 322, Princeton University

Let S be a connected smooth rigid analytic variety over a p-adic field K and let T be a p-adic local system over S. A celebrated theorem of Liu and Zhu says that if V is de Rham at one classical point, then V is globally de Rham. When S has good...

Apr
29
2024

Joint IAS/Princeton Arithmetic Geometry Seminar

Microlocal Sheaves and Affine Springer Fibers
Pablo Boixeda Alvarez
3:30pm|Fine 322, Princeton University

The resolutions of Slodowy slices $\tilde{S}_{e}$ are symplectic varieties that contain the Springer fiber $(G/B)_{e}$ as a Lagrangian subvariety. In joint work with R. Bezrukavnikov, M. McBreen and Z. Yun, we construct analogues of these spaces for...

May
06
2024

Joint IAS/Princeton Arithmetic Geometry Seminar

The Geometric Langlands Conjecture
Sam Raskin
3:30pm|Simonyi Hall 101 and Remote Access

I will describe the main ideas that go into the proof of the (unramified, global) geometric Langlands conjecture. All of this work is joint with Gaitsgory and some parts are joint with Arinkin, Beraldo, Chen, Faergeman, Lin, and Rozenblyum. I will...

Joint IAS/Princeton Complex Geometry Seminar

Mar
02
2005

Joint IAS/Princeton Complex Geometry Seminar

An Obstruction to Constant Scalar Curvature Kahler Metrics
Julius Ross
2:30pm|West Building Lecture Hall

(Joint work with Richard Thomas) I will discuss K-stability and its relation to constant scalar curvature metrics. This leads to a notion of slope stability for manifolds in terms of its subschemes, which gives an obstruction to finding constant...

Apr
05
2005

Joint IAS/Princeton Complex Geometry Seminar

Asymptotic Geometry of Incomplete Metrics on the Moduli Space of Riemann Surfaces
Zheng Huang
2:30pm|Fine Hall 110

An incomplete metric, the Weil-Petersson metric, has played a significant role in the study of the geometry of Teichmuller space. We will mainly discuss the asymptotics of the curvatures of this metric in this talk. Some aspects of another metric...

Joint IAS/Princeton University Algebraic Geometry Day

Apr
14
2015

Joint IAS/Princeton University Algebraic Geometry Day

Embedding the derived category of a curve into a Fano variety
1:15pm|S-101

According to the conjecture of Bondal, the derived category of coherent sheaves on any smooth projective variety can be embedded as a semiorthogonal component into the derived category of a Fano variety of higher dimension. I will explain how this...

Apr
14
2015

Joint IAS/Princeton University Algebraic Geometry Day

Factorization of birational maps on steroids
Dan Abramovich
2:30pm|S-101

Searching literature you will find the following statement (I'm paraphrasing): "If $X_1,X_2$ are nonsingular schemes proper over a complete DVR $R$ with residue characteristic 0, and $\phi: X_1 \to X_2$ is birational, then $\phi$ can be factored as...

Apr
14
2015

Joint IAS/Princeton University Algebraic Geometry Day

Syzygies, gonality and symmetric products of curves
Robert Lazarsfeld
4:00pm|S-101

In the mid 1980s, Mark Green and I conjectured that one could read off the gonality of an algebraic curve $C$ from the syzygies among the equations defining any one sufficiently positive embedding of $C$. Ein and I recently noticed that a small...

Joint IAS/Princeton University Algebraic Geometry Seminar

Feb
04
2019

Joint IAS/Princeton University Algebraic Geometry Seminar

Drinfeld's lemma for schemes
5:00pm|Simonyi Hall 101

In the course of constructing the Langlands correspondence for GL(2) over a function field, Drinfeld discovered a surprising fact about the interaction between étale fundamental groups and products of schemes in characteristic p. We state this...

Feb
11
2019

Joint IAS/Princeton University Algebraic Geometry Seminar

On the algebraic Sato–Tate conjecture for abelian varieties
Victoria Cantoral-Farfán
5:00pm|Princeton University, Fine 314

The Sato–Tate conjecture, originally stated for elliptic curves on 1963, predicts the equidistribution of the normalized Frobenius traces with respect to the Sato–Tate measure, given by the pushforward of the Haar measure on SU(2). We would like to...

Feb
18
2019

Joint IAS/Princeton University Algebraic Geometry Seminar

An example of liftings with different Hodge numbers
Shizhang Li
5:00pm|Princeton University, Fine Hall 314

Does a smooth proper variety in positive characteristic know the Hodge number of its liftings? The answer is "of course not". However, it's not that easy to come up with a counter-example. In this talk, I will first introduce the background of this...

Feb
25
2019

Joint IAS/Princeton University Algebraic Geometry Seminar

Vertex algebras and moduli of curves
Nicola Tarasca
5:00pm|Simonyi Hall 101

This talk will focus on geometric realizations of vertex algebras. The Virasoro uniformization provides an incarnation of the Virasoro algebra in the tangent space of the Hodge line bundle on moduli of curves with marked points and local coordinates...

Mar
04
2019

Joint IAS/Princeton University Algebraic Geometry Seminar

Volumes and intersection theory on moduli spaces of Abelian differentials
5:00pm|Simonyi Hall 101

Computing volumes of moduli spaces has significance in many fields. For instance, Witten's conjecture regarding intersection numbers on the Deligne–Mumford moduli space of stable Riemann surfaces has a fascinating connection to the Weil–Petersson...

Mar
11
2019

Joint IAS/Princeton University Algebraic Geometry Seminar

A non-archimedean Ax–Lindemann theorem
5:00pm|Princeton University, Fine 314

A significant step in the Pila–Zannier approach to the André–Oort conjecture is a geometric transcendence result for the uniformization map of modular curves. I will discuss joint work with François Loeser. We prove an analogue of this result in non...

Mar
25
2019

Joint IAS/Princeton University Algebraic Geometry Seminar

Singular Hodge theory of matroids
5:00pm|Simonyi Hall 101

Kazhdan–Lusztig (KL) polynomials for Coxeter groups were introduced in the 1970s, providing deep relationships among representation theory, geometry, and combinatorics. In 2016, Elias, Proudfoot, and Wakefield defined analogous polynomials in the...

Apr
01
2019

Joint IAS/Princeton University Algebraic Geometry Seminar

Motivic Euler products and motivic height zeta functions
Margaret Bilu
5:00pm|Princeton University, Fine Hall 314

The Grothendieck group of varieties over a field k is the quotient of the free abelian group of isomorphism classes of varieties over k by the so-called cut-and-paste relations. It moreover has a ring structure coming from the product of varieties...

Apr
08
2019

Joint IAS/Princeton University Algebraic Geometry Seminar

Macaulayfication of Noetherian schemes
Kęstutis Česnavičius
5:00pm|Simonyi Hall 101

To reduce to resolving Cohen–Macaulay singularities, Faltings initiated the program of "Macaulayfying" a given Noetherian scheme X. Under various assumptions Faltings, Brodmann, and Kawasaki built the sought Cohen–Macaulay modifications without...

Apr
15
2019

Joint IAS/Princeton University Algebraic Geometry Seminar

The p-curvature conjecture in families
Ananth Shankar
5:00pm|Princeton University, Fine Hall 314

The p-curvature conjecture is an analogue of the Hasse principle for arithmetic differential equations. I will discuss this conjecture in the context of families of algebraic varieties, and among other things, demonstrate a proof of the p-curvature...

Apr
22
2019

Joint IAS/Princeton University Algebraic Geometry Seminar

Chow motives, L-functions, and powers of algebraic Hecke characters
Laure Flapan
5:00pm|Simonyi Hall 101

The Langlands and Fontaine–Mazur conjectures in number theory describe when an automorphic representation f arises geometrically, meaning that there is a smooth projective variety X, or more generally a Chow motive M in the cohomology of X, such...

Apr
29
2019

Joint IAS/Princeton University Algebraic Geometry Seminar

Nearby cycles for parity sheaves and the affine Hecke category
Laura Rider
5:00pm|Princeton University, Fine 314

Achar recently introduced a "nearby cycles formalism" in the framework of chain complexes of parity sheaves. In this talk, I'll explain joint work with Achar in which we compute the output of this functor in two related settings. The first is affine...

May
06
2019

Joint IAS/Princeton University Algebraic Geometry Seminar

Hecke orbits and foliations
5:00pm|Simonyi Hall 101

Motivation. Isogenies with a given polarized abelian variety give moduli points in a Hecke orbit. In characteristic zero any Hecke orbit is dense in this moduli space. What can be said about the Zariski closure of a Hecke orbit in positive...

Joint IAS/Princeton University Arithmetic Geometry Seminar

Apr
17
2023

Joint IAS/Princeton University Arithmetic Geometry Seminar

An Application of Motivic Stable Homotopy Computations in Classical Theory
4:30pm|Princeton University, Fine Hall 314

Motivic homotopy theory is a powerful framework for understanding algebraic varieties and the associated algebraic objects. Moreover, computations in the motivic stable homotopy category can also assist in the computation of stable homotopy groups...

Apr
24
2023

Joint IAS/Princeton University Arithmetic Geometry Seminar

A Stacky Perspective on P-adic Non-abelian Hodge Theory
Arthur-Cesar Le Bras
4:30pm|Rubenstein Commons | Meeting Room 5

P-adic non abelian Hodge theory, also known as the p-adic Simpson correspondence, aims at describing p-adic local systems on a smooth rigid analytic variety in terms of Higgs bundles. I will explain in this talk why the « Hodge-Tate stacks »...