Previous Special Year Seminar
Introduction to Equivariant K-theory
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...
The Generalized Pitman-Stanley Flow Polytope
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...
Operadic Structures in Matroid Theory
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...
Zonotopal Algebras, Configuration Spaces, and More
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...
Geometry of the Gaussian Graphical Model of the Cycle
Rodica Dinu
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...
Lorentzian Polynomials and the Incidence Geometry of Tropical Linear Spaces
Jayden Wang
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...
Algebra for Oscillators: Khovanskii Bases
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...
Products of Chern Classes of Matroid Tautological Bundles (continued)
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...
Felipe Rincón
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...
Products of Chern Classes of Matroid Tautological Bundles
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...