English
Related papers

Related papers: Sparser Abelian High Dimensional Expanders

200 papers

The main purpose of the paper is to study hyperkahler structures from the viewpoint of symplectic geometry. We introduce a notion of hypersymplectic structures which encompasses that of hyperkahler structures. Motivated by the work of…

dg-ga · Mathematics 2008-02-03 Ping Xu

We introduce a natural map from the space of pure-type complex differential forms on a complex manifold to the corresponding one on the infinitesimal deformations of this complex manifold. By use of this map, we generalize an extension…

Complex Variables · Mathematics 2017-10-18 Sheng Rao , Quanting Zhao

In a recent breakthrough, Kelley and Meka (FOCS 2023) obtained a strong upper bound on the density of sets of integers without nontrivial three-term arithmetic progressions. In this work, we extend their result, establishing similar bounds…

Combinatorics · Mathematics 2025-02-13 Yuval Filmus , Hamed Hatami , Kaave Hosseini , Esty Kelman

In graph theory there are intimate connections between the expansion properties of a graph and the spectrum of its Laplacian. In this paper we define a notion of combinatorial expansion for simplicial complexes of general dimension, and…

Combinatorics · Mathematics 2016-07-12 Ori Parzanchevski , Ron Rosenthal , Ran J. Tessler

We give examples of infinitely extendable (not as cones) arithmetically Cohen-Macaulay and arithmetically Gorenstein subvarieties of projective spaces and which are not complete intersections. The proof uses the computation of the dimension…

Algebraic Geometry · Mathematics 2021-02-15 Edoardo Ballico

We establish sparsity and summability results for coefficient sequences of Wiener-Hermite polynomial chaos expansions of countably-parametric solutions of linear elliptic and parabolic divergence-form partial differential equations with…

Numerical Analysis · Mathematics 2023-06-21 Dinh Dũng , Van Kien Nguyen , Christoph Schwab , Jakob Zech

Let X be a compact Kahler manifold with a non-trivial holomorphic Poisson structure. Then there exist deformations of non-trivial generalized Kahler structures with one pure spinor on X. We prove that every Poisson submanifold of X is a…

Differential Geometry · Mathematics 2009-07-16 Ryushi Goto

We present a novel Bayesian approach for high-dimensional grouped regression under sparsity. We leverage a sparse projection method that uses a sparsity-inducing map to derive an induced posterior on a lower-dimensional parameter space. Our…

Methodology · Statistics 2026-05-25 Samhita Pal , Subhashis Ghosal

The problems of random projections and sparse reconstruction have much in common and individually received much attention. Surprisingly, until now they progressed in parallel and remained mostly separate. Here, we employ new tools from…

Data Structures and Algorithms · Computer Science 2010-06-01 Nir Ailon , Edo Liberty

This paper is a sequel to [Caine A., Pickrell D., arXiv:0710.4484], where we studied the Hamiltonian systems which arise from the Evens-Lu construction of homogeneous Poisson structures on both compact and noncompact type symmetric spaces.…

Symplectic Geometry · Mathematics 2008-10-07 Doug Pickrell

Assumed that the parameters of a generalized hypergeometric function depend linearly on a small variable $\varepsilon$, the successive derivatives of the function with respect to that small variable are evaluated at $\varepsilon=0$ to…

Mathematical Physics · Physics 2015-06-15 David Greynat , Javier Sesma

We study symplectic forms on hypersurface algebroids. These are a broad generalization of the $b^{k}$-Poisson structures studied extensively by Miranda, Scott, and collaborators, and their geometry is intimately related to the group of…

Differential Geometry · Mathematics 2026-02-17 Francis Bischoff , Aldo Witte

We construct a complex of toric varieties we call the quasisymmetric Grassmannian inside the Grassmannian of $r$-planes in $\mathbb{C}^n$. Each irreducible component is a positroid variety and an $S_n$ translate of a toric Richardson…

Algebraic Geometry · Mathematics 2026-04-29 Nantel Bergeron , Lucas Gagnon , Hunter Spink , Vasu Tewari

We realize the simple Lie superalgebra G(3) as supersymmetry of various geometric structures, most importantly super-versions of the Hilbert-Cartan equation (SHC) and Cartan's involutive PDE system that exhibit G(2) symmetry. We provide the…

Differential Geometry · Mathematics 2021-06-14 Boris Kruglikov , Andrea Santi , Dennis The

We propose a new method for obtaining complete asymptotic expansions in a systematic manner, which is suitable for counting sequences of various graph families in dense regime. The core idea is to encode the two-dimensional array of…

Combinatorics · Mathematics 2024-12-02 Sergey Dovgal , Khaydar Nurligareev

Expansions of Lie algebras are the opposite process of contractions. Starting from a Lie algebra, the expansion process goes to another one, non-isomorphic and less abelian. We propose an expansion method based in the Casimir invariants of…

Mathematical Physics · Physics 2009-10-31 Francisco J. Herranz , Mariano Santander

A family of nonparametric Yang Baxter (YB) maps is constructed by refactorization of the product of two 2 by 2 matrix polynomials of first degree. These maps are Poisson with respect to the Sklyanin bracket. For each Casimir function a…

Quantum Algebra · Mathematics 2015-05-13 Theodoros E. Kouloukas , Vassilios G. Papageorgiou

The Hamiltonian approach to isomonodromic deformation systems is extended to include generic rational covariant derivative operators on the Riemann sphere with irregular singularities of arbitrary Poincar\'e rank. The space of rational…

Exactly Solvable and Integrable Systems · Physics 2023-08-08 M. Bertola , J. Harnad , J. Hurtubise

It is known that self-adjoint Hamiltonians with purely discrete eigenvalues can be written as (infinite) linear combination of mutually orthogonal projectors with eigenvalues as coefficients of the expansion. The projectors are defined by…

Mathematical Physics · Physics 2020-10-13 Fabio Bagarello , Sergey Kuzhel
‹ Prev 1 4 5 6 7 8 10 Next ›