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Related papers: Regge calculus from discontinuous metrics

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We consider two versions of quantum Regge calculus. The Standard Regge Calculus where the quadratic link lengths of the simplicial manifold vary continuously and the Z_2-Regge Model where they are restricted to two possible values. The goal…

High Energy Physics - Lattice · Physics 2009-10-31 E. Bittner , A. Hauke , H. Markum , J. Riedler , C. Holm , W. Janke

Considered are I class constraints in the tetrad-connection formulation of Regge calculus. One of these is well-known Gauss law which generates rotations in the local frames associated with tetrahedrons in the continuous time 3D section.…

General Relativity and Quantum Cosmology · Physics 2007-05-23 V. Khatsymovsky

Although Regge finite element functions are not continuous, useful generalizations of nonlinear derivatives like the curvature, can be defined using them. This paper is devoted to studying the convergence of the finite element lifting of a…

Numerical Analysis · Mathematics 2024-11-05 Jay Gopalakrishnan , Michael Neunteufel , Joachim Schöberl , Max Wardetzky

The functional integral measure in the 4D Regge calculus normalised w.r.t. the DeWitt supermetric on the space of metrics is considered. The Faddeev-Popov factor in the measure is shown according to the previous author's work on the…

General Relativity and Quantum Cosmology · Physics 2009-10-31 V. M. Khatsymovsky

We investigate pinched geometries in a two-dimensional Lorentzian model of quantum Regge calculus (QRC) using the tensor renormalization group (TRG) method. A pinched geometry refers to a configuration with an infinitely long temporal…

High Energy Physics - Theory · Physics 2026-01-21 Yoshiyasu Ito , Daisuke Kadoh , Yuki Sato

We consider simplest piecewise flat manifold consisting of two identical 4-tetrahedra (call it bisimplex). General relativity action for arbitrary piecewise flat manifold can be expressed in terms of sum of the (half of) bisimplex actions.…

General Relativity and Quantum Cosmology · Physics 2008-10-09 V. M. Khatsymovsky

In Regge calculus the space-time manifold is approximated by certain abstract simplicial complex, called a pseudo-manifold, and the metric is approximated by an assignment of a length to each 1-simplex. In this paper for each pseudomanifold…

General Relativity and Quantum Cosmology · Physics 2017-04-06 Marcin Kisielowski

Discretization of general relativity is a promising route towards quantum gravity. Discrete geometries have a finite number of degrees of freedom and can mimic aspects of quantum geometry. However, selection of the correct discrete freedoms…

General Relativity and Quantum Cosmology · Physics 2018-02-28 Seth K. Asante , Bianca Dittrich , Hal M. Haggard

The metric tensor of a Riemannian manifold can be approximated using Regge finite elements and such approximations can be used to compute approximations to the Gauss curvature and the Levi-Civita connection of the manifold. It is shown that…

Numerical Analysis · Mathematics 2024-02-14 Jay Gopalakrishnan , Michael Neunteufel , Joachim Schöberl , Max Wardetzky

We demonstrate by explicit calculation of the DeWitt-like measure in two-dimensional quantum Regge gravity that it is highly non-local and that the average values of link lengths $l, <l^n>$, do not exist for sufficient high powers of $n$.…

General Relativity and Quantum Cosmology · Physics 2009-10-30 J. Ambjorn , J. Nielsen , J. Rolf , G. Savvidy

We investigate quantum gravity in four dimensions using the Regge approach on triangulations of the four-torus with general, non-regular incidence matrices. We find that the simplicial lattice tends to develop spikes for vertices with low…

High Energy Physics - Lattice · Physics 2009-10-22 Wolfgang Beirl , Harald Markum , J"urgen Riedler

We study the fractal structure of the surface in two-dimensional quantum Regge calculus by performing Monte Carlo simulation with up to 200,000 triangles. The result can be compared with the universal scaling function obtained analytically…

High Energy Physics - Lattice · Physics 2009-10-22 Jun Nishimura , Masaki Oshikawa

Standard Regge Calculus provides an interesting method to explore quantum gravity in a non-perturbative fashion but turns out to be a CPU-time demanding enterprise. One therefore seeks for suitable approximations which retain most of its…

High Energy Physics - Lattice · Physics 2007-05-23 E. Bittner , A. Hauke , C. Holm , W. Janke , H. Markum , J. Riedler

Starting from the canonical phase space for discretised (4d) BF-theory, we implement a canonical version of the simplicity constraints and construct phase spaces for simplicial geometries. Our construction allows us to study the connection…

General Relativity and Quantum Cosmology · Physics 2011-03-03 Bianca Dittrich , James P. Ryan

In the (3+1)D Hamiltonian Regge calculus (one of the coordinates, $ t$, is continuous) conjugate variables are (defined on triangles of discrete 3D section $ t=const$) finite connections and antisymmetric area bivectors. The latter,…

General Relativity and Quantum Cosmology · Physics 2010-04-06 V. Khatsymovsky

Geodesic deviation is the most basic manifestation of the influence of gravitational fields on matter. We investigate geodesic deviation within the framework of Regge calculus, and compare the results with the continuous formulation of…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Sukanya Chakrabarti , Adrian P. Gentle , Arkady Kheyfets , Warner A. Miller

A comparative analysis of the versions of quantum measure in the area tensor Regge calculus is performed on the simplest configurations of the system. The quantum measure is constructed in such the way that it reduces to the Feynman path…

General Relativity and Quantum Cosmology · Physics 2009-11-10 V. M. Khatsymovsky

We use moving frame techniques to derive a notion of curvature for a class of piecewise-smooth Riemannian metrics called Regge metrics, showing that it is a measure that simultaneously satisfies the (weak) Cartan structure equations and the…

Differential Geometry · Mathematics 2026-02-03 Evan S. Gawlik , Jack McKee

Regge calculus is a powerful method to approximate a continuous manifold by a simplicial lattice, keeping the connectivities of the underlying lattice fixed and taking the edge lengths as degrees of freedom. The discrete Regge model…

High Energy Physics - Lattice · Physics 2008-11-26 E. Bittner , W. Janke , H. Markum

We describe the first discrete-time 4-dimensional numerical application of Regge calculus. The spacetime is represented as a complex of 4-dimensional simplices, and the geometry interior to each 4-simplex is flat Minkowski spacetime. This…

General Relativity and Quantum Cosmology · Physics 2009-10-30 Adrian P. Gentle , Warner A. Miller