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Related papers: Square-densities, and volume forms

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We compute the volume of the convex N^2-1 dimensional set M_N of density matrices of size N with respect to the Hilbert-Schmidt measure. The hyper--area of the boundary of this set is also found and its ratio to the volume provides an…

Quantum Physics · Physics 2009-11-10 Karol Zyczkowski , Hans-Juergen Sommers

We introduce a modified Regge calculus for general relativity on a triangulated four dimensional Riemannian manifold where the fundamental variables are areas and a certain class of angles. These variables satisfy constraints which are…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Bianca Dittrich , Simone Speziale

We show that in the Snyder space the area of the disc and of the sphere can be quantized. It is also shown that the area spectrum of the sphere can be related to the Bekenstein conjecture for the area spectrum of a black hole horizon.

High Energy Physics - Theory · Physics 2008-11-26 Juan M. Romero , Adolfo Zamora

An algebraic formulation of Riemannian geometry on quantum spaces is presented, where Riemannian metric, distance, Laplacian, connection, and curvature have their counterparts. This description is also extended to complex manifolds.…

q-alg · Mathematics 2009-10-28 Pei-Ming Ho

It is shown that the definition for the volume of stationary black holes advocated in hep-th/0508108 readily generalizes to the case of dilaton gravity in D=2. The dilaton field is included as part of the measure. A feature observed in D=3…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Daniel Grumiller

Maxwell's equations in the vacuum can be formally cast in the form of Schr\"odinger's equation. Unfortunately, the vector to which this equation directly applies is not a wavefunction: its amplitude squared is not a probability density but…

Quantum Physics · Physics 2025-07-30 Stéphane Virally

We compute the asymptotic expansion of the volume of small sub-Riemannian balls in a contact 3-dimensional manifold, and we express the first meaningful geometric coefficients in terms of geometric invariants of the sub-Riemannian structure

Differential Geometry · Mathematics 2018-12-05 Davide Barilari , Ivan Beschastnyi , Antonio Lerario

We show that the volume of any Riemannian metric on a three sphere is bounded below by the length of the shortest closed curve that links its antipodal image. In particular, the volume is bounded below by the minimum of the length of the…

Differential Geometry · Mathematics 2007-05-23 Christopher B. Croke

Hypersurfaces embedded in conformal manifolds appear frequently as boundary data in boundary-value problems in cosmology and string theory. Viewed as the non-null conformal infinity of a spacetime, we consider hypersurfaces embedded in a…

Differential Geometry · Mathematics 2023-02-06 Samuel Blitz

We review recent progress on two closely related sets of questions concerning convex co-compact hyperbolic manifolds, or convex domains in those manifolds, such as their convex core. The first set of questions is to what extent the…

Geometric Topology · Mathematics 2025-10-08 Jean-Marc Schlenker

In his paper "On the Schlafli differential equality", J. Milnor conjectured that the volume of n-dimensional hyperbolic and spherical simplices, as a function of the dihedral angles, extends continuously to the closure of the space of…

Geometric Topology · Mathematics 2007-05-23 Igor Rivin

Spatial symmetries of the densities appearing in the nuclear Density Functional Theory are discussed. General forms of the local densities are derived by using methods of construction of isotropic tensor fields. The spherical and axial…

Nuclear Theory · Physics 2010-07-21 S. G. Rohozinski , J. Dobaczewski , W. Nazarewicz

We consider locally symmetric manifolds with a fixed universal covering, and construct for each such manifold M a simplicial complex R whose size is proportional to the volume of M. When M is non-compact, R is homotopically equivalent to M,…

Group Theory · Mathematics 2007-05-23 Tsachik Gelander

We establish a min-max estimate on the volume width of a closed Riemannian manifold with nonnegative Ricci curvature. More precisely, we show that every closed Riemannian manifold with nonnegative Ricci curvature admits a PL Morse function…

Differential Geometry · Mathematics 2014-08-21 Stéphane Sabourau

Under a condition that breaks the volume doubling barrier, we obtain a time polynomial structure result on the space of ancient caloric functions with polynomial growth on manifolds. As a byproduct, it is shown that the finiteness result…

Differential Geometry · Mathematics 2025-02-19 Fanghua Lin , Hongbing Qiu , Jun Sun , Qi S. Zhang

In the construction of spectral manifolds in noncommutative geometry, a higher degree Heisenberg commutation relation involving the Dirac operator and the Feynman slash of real scalar fields naturally appears and implies, by equality with…

High Energy Physics - Theory · Physics 2015-03-10 Ali H. Chamseddine , Alain Connes , Viatcheslav Mukhanov

In the 1-dimensional matrix model one identifies the tachyon field in the asymptotic region with a nonlocal transform of the density of fermions. But there is a problem in relating the classical tachyon field with the surface profile of the…

High Energy Physics - Theory · Physics 2014-11-18 Sumit R. Das , Samir D. Mathur

We discuss some additivity properties of the simplicial volume for manifolds with boundary: we give proofs of additivity for glueing amenable boundary components and of superadditivity for glueing amenable submanifolds of the boundary, and…

Algebraic Topology · Mathematics 2015-12-08 Thilo Kuessner

We introduce a numerical method to obtain approximate eigenvalues for some problems of Sturm-Liouville type. As an application, we consider an infinite square well in one dimension in which the mass is a function of the position. Two…

Quantum Physics · Physics 2014-02-24 Juan Jose Alvarez , Manuel Gadella , Luis Pedro Lara

It is shown that the Chern-Simons functional, built in the spinor representation from the initial data on spacelike hypersurfaces, is invariant with respect to infinitesimal conformal rescalings if and only if the vacuum Einstein equations…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Laszlo B Szabados