Lorentzian polynomials

P Brändén, J Huh - Annals of Mathematics, 2020 - projecteuclid.org
We study the class of Lorentzian polynomials. The class contains homogeneous stable
polynomials as well as volume polynomials of convex bodies and projective varieties. We …

The Hodge theory of Soergel bimodules

B Elias, S Makisumi, U Thiel, G Williamson… - Introduction to Soergel …, 2020 - Springer
In this chapter, we survey Elias and Williamson's proof of Soergel's conjecture on the
characters of Soergel bimodules. Their work actually establishes a “Hodge theory” for …

Stellahedral geometry of matroids

C Eur, J Huh, M Larson - Forum of Mathematics, Pi, 2023 - cambridge.org
We use the geometry of the stellahedral toric variety to study matroids. We identify the
valuative group of matroids with the cohomology ring of the stellahedral toric variety and …

Log-concave polynomials II: high-dimensional walks and an FPRAS for counting bases of a matroid

N Anari, K Liu, SO Gharan, C Vinzant - … of the 51st Annual ACM SIGACT …, 2019 - dl.acm.org
We design an FPRAS to count the number of bases of any matroid given by an independent
set oracle, and to estimate the partition function of the random cluster model of any matroid …

Improved analysis of higher order random walks and applications

VL Alev, LC Lau - Proceedings of the 52nd Annual ACM SIGACT …, 2020 - dl.acm.org
The motivation of this work is to extend the techniques of higher order random walks on
simplicial complexes to analyze mixing times of Markov chains for combinatorial problems …

Log-concave polynomials, entropy, and a deterministic approximation algorithm for counting bases of matroids

N Anari, SO Gharan, C Vinzant - 2018 IEEE 59th Annual …, 2018 - ieeexplore.ieee.org
We give a deterministic polynomial time 2^ O (r)-approximation algorithm for the number of
bases of a given matroid of rank r and the number of common bases of any two matroids of …

[PDF][PDF] Singular Hodge theory for combinatorial geometries

T Braden, J Huh, JP Matherne… - arXiv preprint arXiv …, 2020 - math.princeton.edu
We introduce the intersection cohomology module of a matroid and prove that it satisfies
Poincaré duality, the hard Lefschetz theorem, and the Hodge–Riemann relations. As …

Valuative invariants for large classes of matroids

L Ferroni, B Schröter - Journal of the London Mathematical …, 2024 - Wiley Online Library
We study an operation in matroid theory that allows one to transition a given matroid into
another with more bases via relaxing a stressed subset. This framework provides a new …

Tautological classes of matroids

A Berget, C Eur, H Spink, D Tseng - Inventiones mathematicae, 2023 - Springer
We introduce certain torus-equivariant classes on permutohedral varieties which we call
“tautological classes of matroids” as a new geometric framework for studying matroids …

Combinatorial Lefschetz theorems beyond positivity

K Adiprasito - arXiv preprint arXiv:1812.10454, 2018 - arxiv.org
Consider a simplicial complex that allows for an embedding into $\mathbb {R}^ d $. How
many faces of dimension $\frac {d}{2} $ or higher can it have? How dense can they be? This …