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This paper investigates sufficient and necessary conditions for the existence of a homotopy equivalence between two finite simplicial complexes from an algorithmic point of view. As a result, the conditions are formulated in terms of the…

Algebraic Topology · Mathematics 2025-12-25 Mária Šimková

In this paper, we investigate the minimization of a functional in which the usual perimeter is competing with a nonlocal singular term comparable (but not necessarily equal to) a fractional perimeter. The motivation for this problem is a…

Analysis of PDEs · Mathematics 2020-09-09 Antoine Mellet , Yijing Wu

This work provides two sufficient conditions in terms of sections or projections for a convex body to be a polytope. These conditions are necessary as well.

Metric Geometry · Mathematics 2021-10-05 Sergii Myroshnychenko

Using an estimate, we prove that if solution of the spherically symmetric Einstein-Vlasov-Maxwell system develops a singularity at all time, then the first one has to appear at the center of symmetry.

General Relativity and Quantum Cosmology · Physics 2007-05-23 Pierre Noundjeu

In this paper we study non-singular vacuum static space-times with non-zero cosmological constant. We introduce new integral quantities, and under suitable assumptions we prove their monotonicity along the level set flow of the static…

Differential Geometry · Mathematics 2022-03-10 Stefano Borghini , Lorenzo Mazzieri

Through tropical normal idempotent matrices, we introduce isocanted alcoved polytopes, computing their $f$--vectors and checking the validity of the following five conjectures: B\'{a}r\'{a}ny, unimodality, $3^d$, flag and cubical lower…

Combinatorics · Mathematics 2020-09-30 María Jesús de la Puente , Pedro Luis Clavería

We compute explicitely the best constants and, by solving some functional equations, we find all maximizers for homogeneous Strichartz estimates for the Schrodinger equation and for the wave equation in the cases when the Lebesgue exponent…

Analysis of PDEs · Mathematics 2007-05-23 Damiano Foschi

We prove upper bounds on the graph diameters of polytopes in two settings. The first is a worst-case bound for polytopes defined by integer constraints in terms of the height of the integers and certain subdeterminants of the constraint…

Combinatorics · Mathematics 2022-09-16 Hariharan Narayanan , Rikhav Shah , Nikhil Srivastava

We present a way of computing Kronecker coefficients that uses a new family of rational convex polytopes, called column-row polytopes. We give several different formulas for the computation. They are alternating sums of numbers of integer…

Combinatorics · Mathematics 2026-01-05 Ernesto Vallejo , Pedro David Sánchez Salazar

We prove an old conjecture of McMullen, Schneider and Shephard that every polytope with the generating property is strongly monotypic. The other direction is already known, which implies that strong monotypy and the generating property for…

Combinatorics · Mathematics 2025-07-15 Vuong Bui

In the first part of this doctoral thesis we develop a regularity theory for a polyconvex functional in compressible elasticity. In the second part, we will concentrate on uniqueness questions in various situations of finite elasticity.…

Analysis of PDEs · Mathematics 2022-10-27 Marcel Dengler

In [7], a notion of constant scalar curvature metrics on piecewise flat manifolds is defined. Such metrics are candidates for canonical metrics on discrete manifolds. In this paper, we define a class of vertex transitive metrics on certain…

Differential Geometry · Mathematics 2010-09-17 Daniel Champion , Andrew Marchese , Jacob Miller , Andrea Young

Previous research established that the maximal rank of the abstract regular polytopes whose automorphism group is a transitive proper subgroup of $\mbox{S}_n$ is $n/2 + 1$. Up to isomorphism and duality, when $n\geq 12$, there are only two…

Combinatorics · Mathematics 2025-10-07 Maria Elisa Fernandes , Claudio Alexandre Piedade

The condition for pressure isotropy is reduced to a recurrence equation with variable, rational coefficients of order three. We prove that this difference equation can be solved in general. Consequently we can find an exact solution to the…

General Relativity and Quantum Cosmology · Physics 2009-11-11 A. J. John , S. D. Maharaj

We explore the optimality of the constants making valid the recently established Little Grothendieck inequality for JB$^*$-triples and JB$^*$-algebras. In our main result we prove that for each bounded linear operator $T$ from a…

Operator Algebras · Mathematics 2022-04-25 Ondřej F. K. Kalenda , Antonio M. Peralta , Hermann Pfitzner

We consider the best constant in a critical Sobolev inequality of second order. We show non-rigidity for the optimizers above a certain threshold, namely we prove that the best constant is achieved by a non-constant solution of the…

Analysis of PDEs · Mathematics 2019-10-11 Denis Bonheure , Hussein Cheikh Ali , Robson Nascimento

A class of optimal control problems governed by semilinear parabolic equations with mixed pointwise constraints is considered. We give some criteria under which the first and second-order optimality conditions are of KKT-type. We then prove…

Optimization and Control · Mathematics 2024-02-06 Huynh Khanh , Bui Trong Kien

We study positive solutions of semilinear elliptic equations in a planar triangular domain under mixed boundary conditions, consisting of homogeneous Dirichlet boundary conditions on one side and homogeneous Neumann boundary conditions on…

Analysis of PDEs · Mathematics 2026-02-25 Rui Li , Ruofei Yao

The paper concerns the necessary maximum principle for robust optimal control problems of quadratic BSDEs. The coefficient of the systems depends on the parameter $\theta$, and the generator of BSDEs is of quadratic growth in $z$. Since the…

Optimization and Control · Mathematics 2024-01-17 Tao Hao , Jiaqiang Wen , Qi Zhang

Stationary and isotropic iteration stable random tessellations are considered, which can be constructed by a random process of cell division. The collection of maximal polytopes at a fixed time $t$ within a convex window $W\subset{\Bbb…

Probability · Mathematics 2011-04-05 Tomasz Schreiber , Christoph Thaele