Results 21 to 30 of about 7,009 (143)
The systole of random hyperbolic 3‐manifolds
Abstract We study the systole of a model of random hyperbolic 3‐manifolds introduced in Petri and Raimbault [Comment. Math. Helv. 97 (2022), no. 4, 729–768], answering a question posed in that same article. These are compact manifolds with boundary constructed by randomly gluing truncated tetrahedra along their faces.
Anna Roig‐Sanchis
wiley +1 more source
A tropical approach to rigidity: Counting realisations of frameworks
Abstract A realisation of a graph in the plane as a bar‐joint framework is rigid if there are finitely many other realisations, up to isometries, with the same edge lengths. Each of these finitely many realisations can be seen as a solution to a system of quadratic equations prescribing the distances between pairs of points.
Oliver Clarke +6 more
wiley +1 more source
Group field theories for all loop quantum gravity
Group field theories represent a 2nd quantized reformulation of the loop quantum gravity state space and a completion of the spin foam formalism. States of the canonical theory, in the traditional continuum setting, have support on graphs of arbitrary ...
Oriti, Daniele +2 more
core +1 more source
Rigidity of anti‐de Sitter (2+1)‐spacetimes with convex boundary near the Fuchsian locus
Abstract We prove that globally hyperbolic compact anti‐de Sitter (2+1)‐spacetimes with a strictly convex spacelike boundary that is either smooth or polyhedral and whose holonomy is close to Fuchsian are determined by the induced metric on the boundary.
Roman Prosanov, Jean‐Marc Schlenker
wiley +1 more source
Incidence combinatorics of resolutions
We introduce notions of combinatorial blowups, building sets, and nested sets for arbitrary meet-semilattices. This gives a common abstract framework for the incidence combinatorics occurring in the context of De Concini-Procesi models of subspace ...
Dmitry, Eva-maria Feichtner, N. Kozlov
core +4 more sources
Toric amplitudes and universal adjoints
Abstract A toric amplitude is a rational function associated with a simplicial polyhedral fan. The definition is inspired by scattering amplitudes in particle physics. We prove algebraic properties of such amplitudes and study the geometry of their zero loci. These hypersurfaces play the role of Warren's adjoint via a dual volume interpretation.
Simon Telen
wiley +1 more source
Group field theories generating polyhedral complexes
Group field theories are a generalization of matrix models which provide both a second quantized reformulation of loop quantum gravity as well as generating functions for spin foam models.
Thürigen, Johannes
core +1 more source
Canonical forms of oriented matroids
Abstract Positive geometries are semialgebraic sets equipped with a canonical differential form whose residues mirror the boundary structure of the geometry. Every full‐dimensional projective polytope is a positive geometry. Motivated by the canonical forms of polytopes, we construct a canonical form for any tope of an oriented matroid inside the Orlik–
Christopher Eur, Thomas Lam
wiley +1 more source
Moments, sums of squares, and tropicalization
Abstract We use tropicalization to study the duals to cones of nonnegative polynomials and sums of squares on a semialgebraic set S$S$. The truncated cones of moments of measures supported on the set S$S$ are dual to nonnegative polynomials on S$S$, while “pseudomoments” are dual to sums of squares approximations to nonnegative polynomials.
Grigoriy Blekherman +4 more
wiley +1 more source
The Cox ring of a complexity-one horospherical variety
Cox rings are intrinsic objects naturally generalizing homogeneous coordinate rings of projective spaces. A complexity-one horospherical variety is a normal variety equipped with a reductive group action whose general orbit is horospherical and of ...
Langlois, Kevin, Terpereau, Ronan
core +3 more sources

