Previous Special Year Seminar

Mar
05
2025

Special Year Seminar I

Introduction to Equivariant K-theory
2:00pm|Simonyi 101

K-theory arose in the 1950s from Grothendieck’s formulation of the Riemann-Roch theorem – that is, from attempts to calculate spaces of sections of vector bundles on a variety X via intersection theory on X.  An equivariant version was introduced...

Feb
26
2025

Special Year Seminar I

The Generalized Pitman-Stanley Flow Polytope
2:00pm|Simonyi 101

In 1999, Pitman and Stanley introduced the polytope bearing their name along with a study of its faces, lattice points, and volume. This polytope is well-studied due to its connections to parking functions, lattice path matroids, generalized...

Feb
20
2025

Special Year Seminar II

Operadic Structures in Matroid Theory
10:00am|Simonyi 101

I will start by a gentle introduction to operadic structures by drawing a parallel with classical associative structures. Then we will see how those structures can be applied to matroid theory via three examples: Chow rings, Orlik--Solomon algebras...

Feb
19
2025

Special Year Seminar I

Zonotopal Algebras, Configuration Spaces, and More
2:00pm|Simonyi 101

We consider the space of configurations of n points in the three-sphere $S^3$, some of which may coincide and some of which may not, up to the free and transitive action of $SU(2)$ on $S^3$. We prove that the cohomology ring with rational...

Feb
13
2025

Special Year Seminar II

Geometry of the Gaussian Graphical Model of the Cycle
Rodica Dinu
11:00am|Simonyi 101

Algebraic statistics employs techniques in algebraic geometry, commutative algebra and combinatorics, to address problems in statistics and its applications. The philosophy of algebraic statistics is that statistical models are algebraic varieties...

Feb
13
2025

Special Year Seminar II

Lorentzian Polynomials and the Incidence Geometry of Tropical Linear Spaces
Jayden Wang
10:00am|Simonyi 101

The theory of stable polynomials features a key notion called proper position, which generalizes interlacing of real roots to higher dimensions. I will show how a Lorentzian analog of proper position connects the structure of spaces of Lorentzian...

Feb
12
2025

Special Year Seminar I

Algebra for Oscillators: Khovanskii Bases
2:00pm|Simonyi 101

We will present recent applications of enumerative algebra to the study of stationary states in physics. Our point of departure are classical Newtonian differential equations with nonlinear potential. It turns out that the study of their stationary...

Jan
30
2025

Special Year Seminar II

Products of Chern Classes of Matroid Tautological Bundles (continued)
11:00am|Simonyi 101

In 2008, looking to bound the face vectors of tropical linear spaces, Speyer introduced the g-invariant of a matroid, defined in terms of exterior powers of tautological bundles on Grassmannians. He proved its coefficients nonnegative for matroids...

Jan
30
2025

Special Year Seminar II

Tropical Ideals
Felipe Rincón
10:00am|Simonyi 101

Tropical ideals are combinatorial objects that abstract the behavior of the collections of subsets of lattice points that arise as the supports of all polynomials in an ideal. Their structure is governed by a sequence of ‘compatible’ matroids and...

Jan
29
2025

Special Year Seminar I

Products of Chern Classes of Matroid Tautological Bundles
2:00pm|Simonyi 101

In 2008, looking to bound the face vectors of tropical linear spaces, Speyer introduced the g-invariant of a matroid, defined in terms of exterior powers of tautological bundles on Grassmannians. He proved its coefficients nonnegative for matroids...