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Related papers: Squeezed vacua in loop quantum gravity

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This article sheds new light on the problem of cosmological reduction in Loop Quantum Gravity. We critically analyze Quantum Reduced Loop Gravity -- an attempt to extract the cosmological sector of the full theory. We reconsider the…

General Relativity and Quantum Cosmology · Physics 2021-01-12 Jakub Bilski , Antonino Marciano

A new set of twisted geometric variables is introduced to parametrize the holonomy-flux phase space in loop quantum gravity. It is verified that these new geometric variables, after symplectic reduction with respect to the Gauss constraint,…

General Relativity and Quantum Cosmology · Physics 2024-10-15 Gaoping Long , Hongguang Liu , Cong Zhang

Frustrated spin models may lead to the formation of both classical non-collinear spin structures and unique quantum phases including highly entangled quantum spin liquids. Here, we study the entanglement and spatial quantum correlations in…

Strongly Correlated Electrons · Physics 2025-05-29 Levente Rózsa , Dennis Wuhrer , Sebastián A. Díaz , Ulrich Nowak , Wolfgang Belzig

In any attempt to build a quantum theory of gravity, a central issue is to unravel the structure of space-time at the smallest scale. Of particular relevance is the possible definition of coordinate functions within the theory and the study…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Alejandro Corichi , Jose A. Zapata

Coherent states on the quantum group $SU_q(2)$ are defined by using harmonic analysis and representation theory of the algebra of functions on the quantum group. Semiclassical limit $q\rightarrow 1$ is discussed and the crucial role of…

High Energy Physics - Theory · Physics 2010-11-01 I. Ya. Aref'eva , R. Parthasarathy , K. S. Viswanathan , I. V. Volovich

Quantum gravity is expected to be necessary in order to understand situations where classical general relativity breaks down. In particular in cosmology one has to deal with initial singularities, i.e. the fact that the backward evolution…

General Relativity and Quantum Cosmology · Physics 2016-10-19 Martin Bojowald

In previous work we discussed the quantization of paths in spacetime. Building on these ideas we have developed a mathematically coherent theory addressing a number of open questions concerning Loop Quantum Gravity. Our approach develops a…

General Relativity and Quantum Cosmology · Physics 2019-02-07 James Moffat , Charles H. -T. Wang

Loop quantum gravity introduces strong non-perturbative modifications to the dynamical equations in the semi-classical regime, which are responsible for various novel effects, including resolution of the classical singularity in a Friedman…

High Energy Physics - Theory · Physics 2007-05-23 Martin Bojowald , Roy Maartens , Parampreet Singh

We propose a new type of gauge in two-dimensional quantum gravity. We investigate pure gravity in this gauge, and find that the system reduces to quantum mechanics of loop length $l$. Furthermore, we rederive the $c\!=\!0$ string field…

High Energy Physics - Theory · Physics 2009-10-22 M. Fukuma , N. Ishibashi , H. Kawai , M. Ninomiya

When gauge field theory coherent states for loop quantum gravity (LQG) were introduced, an optimized semiclassical proper length emerged, corresponding to the edge length $\epsilon$ of a graph embedded in a given classical geometry. Here…

General Relativity and Quantum Cosmology · Physics 2014-02-20 Paul G. N. de Vegvar

The perturbative consistency of coherent states within interacting quantum field theory requires them to be altered beyond the simple non-squeezed form. Building on this point, we perform explicit construction of consistent squeezed…

High Energy Physics - Theory · Physics 2023-12-01 Lasha Berezhiani , Giordano Cintia , Michael Zantedeschi

Quantum gravity is investigated in the limit of a large number of space-time dimensions, using as an ultraviolet regularization the simplicial lattice path integral formulation. In the weak field limit the appropriate expansion parameter is…

High Energy Physics - Theory · Physics 2008-11-26 Herbert W. Hamber , Ruth M. Williams

Quantum geometry, i.e., the quantum theory of intrinsic and extrinsic spatial geometry, is a cornerstone of loop quantum gravity. Recently, there have been many new ideas in this field, and I will review some of them. In particular, after a…

General Relativity and Quantum Cosmology · Physics 2015-06-03 Hanno Sahlmann

We present a new method for constructing operators in loop quantum gravity. The construction is an application of the general idea of "coherent state quantization", which allows one to associate a unique quantum operator to every function…

General Relativity and Quantum Cosmology · Physics 2015-11-18 Emanuele Alesci , Andrea Dapor , Jerzy Lewandowski , Ilkka Makinen , Jan Sikorski

We construct a state in the loop quantum gravity theory with zero cosmological constant, which should correspond to the flat spacetime vacuum solution. This is done by defining the loop transform coefficients of a flat connection…

General Relativity and Quantum Cosmology · Physics 2009-01-16 A. Mikovic

I briefly review some of the recent progress in quantum field theory in curved spacetime and other aspects of semiclassical gravity, as reported at the D3 Workshop at GR15.

General Relativity and Quantum Cosmology · Physics 2007-05-23 Robert M. Wald

Loop quantum cosmology is a symmetry reduced quantization of cosmological spacetimes based on loop quantum gravity. While it has been successful in resolution of various cosmological singularities and connecting Planck scale physics to…

General Relativity and Quantum Cosmology · Physics 2019-12-25 Klaus Liegener , Parampreet Singh

The study of Gaussian states has arisen to a privileged position in continuous variable quantum information in recent years. This is due to vehemently pursued experimental realisations and a magnificently elegant mathematical framework. In…

Quantum Physics · Physics 2014-03-17 Gerardo Adesso , Sammy Ragy , Antony R. Lee

We review the application of the loop representation to gauge theories and general relativity. The emphasis lies on exhibiting the loop calculus techniques, and their application to the canonical quantization. We discuss the role that knot…

High Energy Physics - Theory · Physics 2009-09-25 Rodolfo Gambini

We recently introduced a new representation for loop quantum gravity, which is based on the BF vacuum and is in this sense much nearer to the spirit of spin foam dynamics. In the present paper we lay out the classical framework underlying…

General Relativity and Quantum Cosmology · Physics 2015-07-03 Bianca Dittrich , Marc Geiller