English
Related papers

Related papers: Bounded ratios for Lorentzian matrices

200 papers

At the heart of convex geometry lies the observation that the volume of convex bodies behaves as a polynomial. Many geometric inequalities may be expressed in terms of the coefficients of this polynomial, called mixed volumes. Among the…

Metric Geometry · Mathematics 2023-09-18 Yair Shenfeld , Ramon van Handel

We study the cone of completely positive (cp) matrices for the first interesting case $n = 5$. This is a semialgebraic set, which means that the polynomial equalities and inequlities that define its boundary can be derived. We characterize…

Optimization and Control · Mathematics 2021-09-02 Max Pfeffer , Jose Alejandro Samper

This paper establishes new upper bounds for the right eigenvalues of monic matrix polynomials over the quaternion division algebra. The noncommutative nature of quaternion multiplication presents fundamental challenges in eigenvalue…

Complex Variables · Mathematics 2026-04-17 Ovaisa Jan , Idrees Qasim

Suppose that a polygon $P$ is given as an array containing the vertices in counterclockwise order. We analyze how many vertices (including the index of each of these vertices) we need to know before we can bound $P$, i.e., report a bounded…

Computational Geometry · Computer Science 2025-09-05 Mikkel Abrahamsen , Jack Stade , Shuyi Yan , Hanwen Zhang

We undertake a detailed study of the $L^2$ discrepancy of rational and irrational 2-dimensional lattices either with or without symmetrization. We give a full characterization of lattices with optimal $L^2$ discrepancy in terms of the…

Number Theory · Mathematics 2024-10-10 Bence Borda

Determinantal varieties -- the sets of bounded-rank matrices or tensors -- have attracted growing interest in low-rank optimization. The tangent cone to low-rank sets is widely studied and underpins a range of geometric methods. The…

Optimization and Control · Mathematics 2025-12-12 Yan Yang , Bin Gao , Ya-xiang Yuan

The formula for analytic torsion of a cone in even dimensions is comprised of three terms. The first two terms are well understood and given by an algebraic combination of the Betti numbers and the analytic torsion of the cone base. The…

Spectral Theory · Mathematics 2015-02-02 Boris Vertman

In this paper we consider arbitrary hexagons on the triangular lattice with three arbitrary bowtie-shaped holes, whose centers form an equilateral triangle. The number of lozenge tilings of such general regions is not expected --- and…

Combinatorics · Mathematics 2020-01-08 Mihai Ciucu , Tri Lai , Ranjan Rohatgi

We investigate regularizations of distributional sections of vector bundles by means of nets of smooth sections that preserve the main regularity properties of the original distributions (singular support, wavefront set, Sobolev…

Functional Analysis · Mathematics 2014-04-07 Shantanu Dave , Guenther Hoermann , Michael Kunzinger

Optimal weighted Sobolev-Lorentz embeddings with homogeneous weights in open convex cones are established, with the exact value of the optimal constant. These embeddings are non-compact, and this paper investigates the structure of their…

Functional Analysis · Mathematics 2025-04-01 Petr Gurka , Jan Lang , Zdeněk Mihula

Motivated by the problem of spherical summability of products of Fourier series, we study the boundedness of the bilinear Bochner-Riesz multipliers $(1-|\xi|^2-|\eta|^2)^\delta_+$ and we make some advances in this investigation. We obtain…

Classical Analysis and ODEs · Mathematics 2013-04-04 Frederic Bernicot , Loukas Grafakos , Liang Song , Lixin Yan

We give lower bounds on the largest singular value of arbitrary matrices, some of which are asymptotically tight for almost all matrices. To study when these bounds are exact, we introduce several combinatorial concepts. In particular, we…

Functional Analysis · Mathematics 2007-05-23 Vladimir Nikiforov

The corner polyhedron is described by minimal valid inequalities from maximal lattice-free convex sets. For the Relaxed Corner Polyhedron (RCP) with two free integer variables and any number of non-negative continuous variables, it is known…

Optimization and Control · Mathematics 2012-04-10 Yogesh P. Awate

We introduce an analogue of the theory of length spaces into the setting of Lorentzian geometry and causality theory. The r\^ole of the metric is taken over by the time separation function, in terms of which all basic notions are…

Differential Geometry · Mathematics 2019-11-07 Michael Kunzinger , Clemens Sämann

Random tilings are interesting as idealizations of atomistic models of quasicrystals and for their connection to problems in combinatorics and algorithms. Of particular interest is the tiling entropy density, which measures the relation of…

Combinatorics · Mathematics 2015-09-21 Maxwell Hutchinson , Michael Widom

This paper investigates and bounds the expected solution quality of combinatorial optimization problems when feasible solutions are chosen at random. Loose general bounds are discovered, as well as families of combinatorial optimization…

Data Structures and Algorithms · Computer Science 2014-02-04 Evan A. Sultanik

Polygons are described as almost-convex if their perimeter differs from the perimeter of their minimum bounding rectangle by twice their `concavity index', $m$. Such polygons are called \emph{$m$-convex} polygons and are characterised by…

Combinatorics · Mathematics 2007-10-26 W. R. G. James , I. Jensen , A. J. Guttmann

We explore the applications of Lorentzian polynomials to the fields of algebraic geometry, analytic geometry and convex geometry. In particular, we establish a series of intersection theoretic inequalities, which we call rKT property, with…

Algebraic Geometry · Mathematics 2024-05-24 Jiajun Hu , Jian Xiao

The emergence of Lorentzian geometries in spin-foams and group field theories is investigated. The spectral dimension of periodic Euclidean spin-foam frusta is studied. At large scales, the spectral dimension is generically four. At lower…

General Relativity and Quantum Cosmology · Physics 2025-06-26 Alexander F. Jercher

The ratio of volume to crossing number of a hyperbolic knot is known to be bounded above by the volume of a regular ideal octahedron, and a similar bound is conjectured for the knot determinant per crossing. We investigate a natural…

Geometric Topology · Mathematics 2018-11-16 Abhijit Champanerkar , Ilya Kofman , Jessica S. Purcell