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This is a continuation of the early paper concerning matroid base polytope decomposition. Here, we will present sufficient conditions on $M$ so its base matroid polytope $P(M)$ has a {\em sequence} of hyperplane splits. The latter yields to…

Combinatorics · Mathematics 2013-11-28 Vanessa Chatelain , Jorge Ramirez Alfonsin

In this article, we establish necessary and sufficient conditions for a polynomial of degree $n$ to have exactly $n$ real roots. A complete study of polynomials of degree five is carried out. The results are compared with those obtained…

Combinatorics · Mathematics 2024-04-01 Jean-Michel Billiot , Eric Fontenas

Let $\mathcal B=\mathcal B_{k,n,p}$ be a random collection of $k$-subsets of $[n]$ where each possible set is present independently with probability $p$. Let $\cal E_{\mathcal B}$ be the event that $\mathcal B$ defines the set of bases of a…

Combinatorics · Mathematics 2026-05-11 Patrick Bennett , Alan Frieze

Alon and F\"uredi (European J. Combin. 1993) gave a tight bound for the following hyperplane covering problem: find the minimum number of hyperplanes required to cover all points of the n-dimensional hypercube {0,1}^n except the origin.…

Combinatorics · Mathematics 2023-08-01 Arijit Ghosh , Chandrima Kayal , Soumi Nandi , S. Venkitesh

Given a rational monomial map, we consider the question of finding a toric variety on which it is algebraically stable. We give conditions for when such variety does or does not exist. We also obtain several precise estimates of the degree…

Dynamical Systems · Mathematics 2010-07-20 Jan-Li Lin

Let $f \colon \mathbb{R}^n \rightarrow \mathbb{R}$ be a polynomial and $\mathcal{Z}(f)$ its zero set. In this paper, in terms of the so-called Newton polyhedron of $f,$ we present a necessary criterion and a sufficient condition for the…

Algebraic Geometry · Mathematics 2017-06-01 Phu-Phat Pham , Tien-Son Pham

In this paper, we first present simple proofs of Choi's results [4], then we give a short alternative proof for Fiedler and Markham's inequality [6]. We also obtain additional matrix inequalities related to partial determinants.

Functional Analysis · Mathematics 2020-03-16 Yongtao Li , Lihua Feng , Zheng Huang , Weijun Liu

We prove the complete monotonicity on $(0,\infty)^n$ for suitable inverse powers of the spanning-tree polynomials of graphs and, more generally, of the basis generating polynomials of certain classes of matroids. This generalizes a result…

Combinatorics · Mathematics 2014-12-04 Alexander D. Scott , Alan D. Sokal

A polynomial $p\in\mathbb{R}[z_1,\dots,z_n]$ is real stable if it has no roots in the upper-half complex plane. Gurvits's permanent inequality gives a lower bound on the coefficient of the $z_1z_2\dots z_n$ monomial of a real stable…

Data Structures and Algorithms · Computer Science 2017-02-10 Nima Anari , Shayan Oveis Gharan

A polynomial with rational coefficients is said to be pure with respect to a rational prime $p$ if its Newton polygon has one slope. In this article, we prove that the number of irreducible factors of the $n$-th iterate of a pure polynomial…

Number Theory · Mathematics 2023-01-31 Mohamed O Darwish , Mohammad Sadek

In this note we show that unsatisfiable systems of linear equations with a constant number of variables per equation over prime finite fields have polynomial-size constant-degree semi-algebraic proofs of unsatisfiability. These are proofs…

Computational Complexity · Computer Science 2015-02-16 Albert Atserias

This paper proves that in Size Theory the comparison of multidimensional size functions can be reduced to the 1-dimensional case by a suitable change of variables. Indeed, we show that a foliation in half-planes can be given, such that the…

Computational Geometry · Computer Science 2007-05-23 Andrea Cerri , Patrizio Frosini , Claudia Landi

We prove an asymptotically tight bound (asymptotic with respect to the number of polynomials for fixed degrees and number of variables) on the number of semi-algebraically connected components of the realizations of all realizable sign…

Combinatorics · Mathematics 2009-07-14 Saugata Basu , Richard Pollack , Marie-Francoise Roy

We introduce G{\aa}rding polynomials, a class of real multivariate polynomials characterized by positivity regions that are invariant under translation by positive vectors and closed under strictly positive affine transformations. We prove…

Combinatorics · Mathematics 2026-05-19 Hao Fang , Biao Ma

A recently-established necessary condition for polynomials that preserve the class of entrywise nonnegative matrices of a fixed order is shown to be necessary and sufficient for the class of nonnegative monomial matrices. Along the way, we…

Rings and Algebras · Mathematics 2024-01-04 Benjamin J. Clark , Pietro Paparella

In unpublished work, Geelen proved that a matroid is near-regular if and only if it has no minor isomorphic to: U2,5; U3,5; the Fano plane and its dual; the non-Fano and its dual; the single-element deletion of AG(2,3), its dual, and the…

Combinatorics · Mathematics 2009-07-12 Rhiannon Hall , Dillon Mayhew , Stefan H. M. van Zwam

It is common in stability analysis to linearize a system and investigate the spectrum of the Jacobian matrix. This approach faces the challenge of determining the matrix spectrum when the coefficients depend on parameters or when the…

Dynamical Systems · Mathematics 2025-03-17 Ziyad AlSharawi , Jose S. Cánovas , Sadok Kallel

We develop the Perron-Frobenius theory using a variational approach and extend it to a set of arbitrary matrices, including those that are neither irreducible nor essentially positive, and non-preserved cones. We introduce a new concept…

Analysis of PDEs · Mathematics 2024-07-19 Yavdat Il'yasov , Nurmukhamet Valeev

The differential systems satisfied by orthogonal polynomials with arbitrary semiclassical measures supported on contours in the complex plane are derived, as well as the compatible systems of deformation equations obtained from varying such…

Exactly Solvable and Integrable Systems · Physics 2018-06-26 M. Bertola , B. Eynard , J. Harnad

Consider a finite collection of affine hyperplanes in $\mathbb R^d$. The hyperplanes dissect $\mathbb R^d$ into finitely many polyhedral chambers. For a point $x\in \mathbb R^d$ and a chamber $P$ the metric projection of $x$ onto $P$ is the…

Metric Geometry · Mathematics 2020-09-02 Zakhar Kabluchko