Previous Conferences & Workshops

Nov
04
2024

Joint IAS/PU Arithmetic Geometry

Etale Cohomology of Shimura Varieties via Coherent Sheaves
3:35pm|*Princeton University, Fine Hall 224*

Studying the \’etale cohomology of Shimura varieties with Hecke and Galois actions provides an avenue toward understanding the Langlands correspondence. 
While the structure of the rational cohomology groups is predicted conjectures of Kottwitz and...

Nov
04
2024

Members' Colloquium

Zeroes of Characters (cf. J.-P. Serre, same title, arXiv 2312.17551)
1:00pm|Simonyi 101 and Remote Access

A promenade in Serre's paper, plus some related results of mine.

Nov
04
2024

Computer Science/Discrete Mathematics Seminar I

Quasi-Linear Size PCPs with Small Soundness from High-Dimensional Expanders
Mitali Bafna
10:30am|Simonyi 101 and Remote Access

The theory of probabilistically checkable proofs (PCPs) shows how to encode a proof for any theorem into a format where the theorem's correctness can be verified by making only a constant number of queries to the proof. The PCP Theorem [ALMSS] is a...

Nov
01
2024

Special Groups and Dynamics Seminar

Counting Representations of Fuchsian Groups Over Finite Fields
Michael Larsen
2:00pm|Simonyi 101

Recent progress on character bounds for groups of Lie type makes it feasible in many cases to find the asymptotic growth, for fixed q and n tending to infinity, of the number of n-dimensional representations of a Fuchsian group G over the field with...

Nov
01
2024

Joint IAS/Princeton/Montreal/Paris/Tel-Aviv Symplectic Geometry Zoominar

Classification of Some Open Toric Domains
Michael Hutchings
9:15am|Remote Access

We show that two generic, open, convex or concave toric domains in $R^4$ are symplectomorphic if and only if they agree up to reflection. The proof uses barcodes in positive $S^1$-equivariant symplectic homology, or equivalently in cylindrical...

Oct
31
2024

Joint PU/IAS Number Theory

Bass Note Spectra of Binary Forms
Giorgos Kotsovolis
3:30pm|Simonyi 101 and Remote Access

In the 1940s Mahler initiated the program of determining the bass note spectrum $$\mathrm{Spec}(P):=\left\{\inf_{\underline{x} \in\Lambda \setminus \underline{0}}\left\vert P(\underline{x})\right\vert, \Lambda \subset \mathbb{R}^k \text{ a...

Oct
31
2024

Special Year Seminar II

MM-curves
Mario Kummer
10:00am|Simonyi 101 and Remote Access

For an embedded stable curve over the real numbers we introduce a hyperplane arrangement in the tangent space of the Hilbert scheme. The connected components of its complement are labeled by embeddings of the graph of the stable curve to a compact...

Oct
30
2024

Mathematical Conversations

The Alexandrov-Fenchel Inequality
6:00pm|Birch Garden, Simons Hall

The Alexandrov-Fenchel inequality---the fundamental log-concavity phenomenon in convex geometry---arose from Minkowski's work in number theory in the late 1800s. It has resurfaced in surprising ways throughout the 20th and 21st centuries in the...

Oct
30
2024

Special Year Seminar I

Complexity of Log-concave Inequalities in Matroids
Swee Hong Chan
2:00pm|Simonyi 101

A sequence of nonnegative real numbers $a_1, a_2, \ldots, a_n$, is log-concave if $a_i^2 \geq a_{i-1}a_{i+1}$ for all $i$ ranging from 2 to $n-1$. Examples of log-concave inequalities range from inequalities that are readily provable, such as the...