Title: Local cohomology of thickenings

Abstract: Let $R$ be a standard graded polynomial ring that is finitely generated over a field, and let $I$ be a homogenous prime ideal of $R$.  A recent paper of Bhatt, Blickle, Lyubeznik, Singh, and Zhang examined the local cohomology of the thickenings $R/I^t$ in characteristic $0$, and provided a stabilization result for these cohomology modules. I will explicitly construct isomorphisms between local cohomology modules of thickenings in several cases.

Title: Symbolic Generic Initial Systems and Matroid Configurations

Abstract: We survey dissertation work of my academic sister Sarah Mayes-Tang (2013 Ph.D.). As time allows, we aim towards two objectives. First, in terms of combinatorial algebraic geometry we weave a narrative from linear star configurations in projective spaces to matroid configurations therein, the latter being a recent development investigated by the quartet of Geramita -- Harbourne -- Migliore -- Nagel. Second, we pitch a prospectus for further work in follow-up to both Sarah's work and the matroid configuration investigation. 

Title: Hyperplane Arrangements and Compactifying the Milnor Fiber

Title: Asymptotic Syzygies for Products of Projective Space

Abstract: I will discuss results describing the asymptotic syzygies of products of projective space, in the vein of the explicit methods of Ein, Erman, and Lazarsfeld’s non-vanishing results on projective space.

Title: Generalized minimum distance functions for schemes and linear codes

Abstract In coding theory, a linear code is a subspace of a finite dimensional vector space. To a linear code one can associate a set of points in projective space. If these points are distinct, then the Hamming distance of the code can be computed based on the geometry of the points. 

Motivated by these considerations, we introduce commutative algebraic generalizations for the notion of Hamming distance, which are better suited for working with non-reduced schemes. We describe the properties of these generalized minimum distance functions, as well as bounding them in the spirit of the classical singleton bound and by means of a Cayley Bacharach-type conjecture.

This talk is based on joint work with Susan Cooper, Stefan Tohaneanu, Maria Vaz Pinto and Rafael Villarreal.

Tropical curves, graph complexes, and the cohomology of M_g



Joint with Søren Galatius and Sam Payne. The cohomology ring H^*(M_g,Q)

of the moduli space of curves of genus g is not fully understood, even

for g small. For example, in the 1980s Harer-Zagier showed that the

Euler characteristic (up to sign) grows super-exponentially with g

---yet most of this cohomology is not explicitly known. I will explain

how we obtained new results on the rational cohomology of moduli

spaces of curves of genus g, via Kontsevich's graph complexes and the

moduli space of tropical curves.

Title: Tropical geometry and amoebas in matrix groups



Abstract: We start with the basic and remarkable notions of amoeba and tropical variety of a subvariety Y in the algebraic torus $(\mathbb{C} \setminus \{0\})^n$. We will demonstrate how these notions lead us to finding a minimal compactification of Y (usually referred to as "tropical compactification"). In the course of this we will introduce the notion of a toric variety as well. Next, I will discuss recent results about extending these notions from the algebraic torus to other matrix groups such as $GL(n, \mathbb{C})$. Some interesting linear algebra, such as singular value decomposition and Smith normal form, pops up. For the most part, I assume only basic background from algebra and geometry and the talk should be understandable to a general math crowd. There will be a nonzero number of pictures!