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Related papers: Simplicity in simplicial phase space

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This paper shows one way to construct phase spaces in special relativity by expanding Minkowski Space. These spaces appear to indicate that we can dispense with gravitational singularities. The key mathematical ideas in the present approach…

Astrophysics · Physics 2007-06-15 Peter Danenhower

In this paper, we address the problem of the dynamics in three dimensional loop quantum gravity with zero cosmological constant. We construct a rigorous definition of Rovelli's generalized projection operator from the kinematical Hilbert…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Karim Noui , Alejandro Perez

We consider the quantization of gravity as an SL(2,C) gauge theory in terms of Ashtekar's selfdual variables and reality conditions for the spatial metric (RCI) and its evolution (RCII). We start from a holomorphic phase space formulation.…

General Relativity and Quantum Cosmology · Physics 2023-10-31 Hanno Sahlmann , Robert Seeger

Spin foam models, loop quantum gravity and group field theory are discussed as quantum gravity candidate theories and usually involve a continuous Lie group. We advocate here to consider quantum gravity inspired models with finite groups,…

General Relativity and Quantum Cosmology · Physics 2011-04-01 Benjamin Bahr , Bianca Dittrich , James P. Ryan

In this work, it is demonstrated how the kinematical Hilbert space of Loop Quantum Gravity (LQG) can be inferred from the configuration space of BF theories via the imposition of the Hamiltonian constraints. In particular, it is outlined…

General Relativity and Quantum Cosmology · Physics 2015-05-20 Francesco Cianfrani

A spin (dependent) system treatment of gravity is adopted akin to the Sen-Ashtekar treatment. Time is reinserted into the space ``fluid'' at the quantum Level. This time - the Lorentzian one- is shown to be a vorticity of a ``fluid…

General Physics · Physics 2011-03-07 Koustubh Kabe

I discuss the use of spinors in the construction of spin-foam models, in particular the form of the closure and simplicity constraints for triangles that are space-like, i.e. with (area)$^2=\half S^{IJ}S_{IJ}>0$, regardless of whether they…

General Relativity and Quantum Cosmology · Physics 2015-06-18 Giorgio Immirzi

The phase structure of four-dimensional simplicial quantum gravity coupled to U(1) gauge fields has been studied using Monte-Carlo simulations. The smooth phase is found in the intermediate region between the crumpled phase and the branched…

High Energy Physics - Lattice · Physics 2009-10-31 S. Horata , H. S. Egawa , N. Tsuda , T. Yukawa

A canonical formalism and constraint analysis for discrete systems subject to a variational action principle are devised. The formalism is equivalent to the covariant formulation, encompasses global and local discrete time evolution moves…

Mathematical Physics · Physics 2013-09-17 Bianca Dittrich , Philipp A Hoehn

The paper concerns the fictitious entanglement of the so-called ``singularities'' in problems, pertaining to quantum gravity, due, in point of fact, to the way we try to employ, in that context, differential geometry, the latter being…

General Physics · Physics 2007-05-23 Anastasios Mallios

The aim of this review paper is to give a panoramic of the impact of spin glass theory and statistical physics in the study of the K-sat problem. The introduction of spin glass theory in the study of the random K-sat problem has indeed left…

Computational Complexity · Computer Science 2014-05-15 Stefano Gogioso

A quantization scheme based on the extension of phase space with application of constrained quantization technic is considered. The obtained method is similar to the geometric quantization. For constrained systems the problem of scalar…

High Energy Physics - Theory · Physics 2009-10-30 George Jorjadze

In quantum gravity, we envision renormalization as the key tool for bridging the gap between microscopic models and observable scales. For spin foam quantum gravity, which is defined on a discretisation akin to lattice gauge theories, the…

General Relativity and Quantum Cosmology · Physics 2020-07-06 Sebastian Steinhaus

In this article we apply background-independent renormalization group methods to spin foam quantum gravity. It is aimed at extending and elucidating the analysis of a companion letter, in which the existence of a fixed point in the…

General Relativity and Quantum Cosmology · Physics 2017-07-21 Benjamin Bahr , Sebastian Steinhaus

We study the state-sum models of quantum gravity based on a representation 2-category of the Poincare 2-group. We call them spin-cube models, since they are categorical generalizations of spin-foam models. A spin-cube state sum can be…

General Relativity and Quantum Cosmology · Physics 2015-06-15 A. Mikovic

In this paper explore the relation between covariant and canonical approaches to quantum gravity and $BF$ theory. We will focus on the dynamical triangulation and spin-foam models, which have in common that they can be defined in terms of…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Matthias Arnsdorf

Spherically symmetric models of loop quantum gravity have been studied recently by different methods that aim to deal with structure functions in the usual constraint algebra of gravitational systems. As noticed by Gambini and Pullin, a…

General Relativity and Quantum Cosmology · Physics 2015-09-09 Martin Bojowald , Suddhasattwa Brahma , Juan D. Reyes

The paper develop the alternative formulation of quantum mechanics known as the phase space quantum mechanics or deformation quantization. It is shown that the quantization naturally arises as an appropriate deformation of the classical…

Mathematical Physics · Physics 2011-09-27 Maciej Blaszak , Ziemowit Domanski

We make a conceptual overview of a particular approach to the initial-value problem in canonical gauge theories. We stress how the first-class phase-space constraints may be relaxed if we interpret them as fixing the values of new degrees…

General Relativity and Quantum Cosmology · Physics 2024-10-08 Roberto Casadio , Leonardo Chataignier , Alexander Yu. Kamenshchik , Francisco G. Pedro , Alessandro Tronconi , Giovanni Venturi

We introduce a family of boundary conditions and point constraints for conformal immersions that increase the controllability of surfaces defined as minimizers of conformal variational problems. Our free boundary conditions fix the metric…

Differential Geometry · Mathematics 2024-11-11 Yousuf Soliman , Ulrich Pinkall , Peter Schröder