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Related papers: Loop Quantum Cosmology and Spin Foams

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This thesis is a compilation of research in relativistic quantum information theory, and research in quantum reference frames. The research in the former category provides a fundamental construction of quantum information theory of…

Quantum Physics · Physics 2013-12-18 Matthew C Palmer

The very early universe provides the best arena we currently have to test quantum gravity theories. The success of the inflationary paradigm in accounting for the observed inhomogeneities in the cosmic microwave background already…

General Relativity and Quantum Cosmology · Physics 2015-06-15 Abhay Ashtekar

Cosmological perturbations are generally described by quantum fields on (curved but) classical space-times. While this strategy has a large domain of validity, it can not be justified in the quantum gravity era where curvature and matter…

General Relativity and Quantum Cosmology · Physics 2015-06-12 Ivan Agullo , Abhay Ashtekar , William Nelson

By incorporating quantum aspects of gravity, Loop Quantum Cosmology (LQC) provides a self-consistent extension of the inflationary scenario, allowing for modifications in the primordial inflationary power spectrum with respect to the…

Cosmology and Nongalactic Astrophysics · Physics 2019-11-01 Micol Benetti , Leila Graef , Rudnei O. Ramos

We propose that the size of the universe and its rate of expansion cannot be simultaneously specified with arbitrary precision, a quantum mechanical statement encoded in a deformed commutation relation for the scale factor. The deformation…

Cosmology and Nongalactic Astrophysics · Physics 2026-05-15 Savvas M. Koushiappas

Guided by recent developments towards the implementation of the deformation quantization program within the Loop Quantum Cosmology (LQC) formalism, in this paper we address the introduction of both the integral and differential…

General Relativity and Quantum Cosmology · Physics 2022-10-04 Jasel Berra-Montiel , Alberto Molgado , Eduardo Torres-Cordero

We propose an approach which, by combining insights from Loop Quantum Gravity (LQG), Topos theory, Non-commutative Geometry \`a la Connes, and spacetime relationalism, provides fertile ground for the search of an adequate spacetime picture…

General Relativity and Quantum Cosmology · Physics 2021-03-12 Alejandro Ascárate

It is shown that only in the space-times admitting a 1+3-foliation by flat Cauchy hypesurfaces (i.e., in the Bianchi I type space-times the isotropic version of which the spatially flat Friedmann-Robertson-Walker space-times are) the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 E. A. Tagirov

This chapter provides a review of the frameworks developed for cosmological perturbation theory in loop quantum cosmology, and applications to various models of the early universe including inflation, ekpyrosis and the matter bounce, with…

General Relativity and Quantum Cosmology · Physics 2024-03-08 Ivan Agullo , Anzhong Wang , Edward Wilson-Ewing

A hidden gauge theory structure of quantum mechanics which is invisible in its conventional formulation is uncovered. Quantum mechanics is shown to be equivalent to a certain Yang-Mills theory with an infinite-dimensional gauge group and a…

High Energy Physics - Theory · Physics 2009-10-31 M. Reuter

A covariant spin-foam formulation of quantum gravity has been recently developed, characterized by a kinematics which appears to match well the one of canonical loop quantum gravity. In this paper we reconsider the implementation of the…

General Relativity and Quantum Cosmology · Physics 2014-11-21 You Ding , Carlo Rovelli

The loop quantization of the conformal Brans-Dicke cosmology is explored in the spatially flat and Bianchi-I setting. The scalar and conformal constraints governing the canonical model are quantized using the loop techniques. The physical…

General Relativity and Quantum Cosmology · Physics 2023-12-29 Chun-Yen Lin , Xiangjing Liu , Yongge Ma , Cong Zhang

This is an introduction to spin foam models for non-perturbative quantum gravity, an approach that lies at the point of convergence of many different research areas, including loop quantum gravity, topological quantum field theories, path…

General Relativity and Quantum Cosmology · Physics 2011-02-16 Daniele Oriti

In the quest of a physical theory of quantum gravity, spin foam models, or in short spinfoams, propose a well-defined path integral summing over quantized discrete space-time geometries. At the crossroad of topological quantum field theory,…

General Relativity and Quantum Cosmology · Physics 2025-01-08 Etera R. Livine

In this work a loop quantum corrected model is obtained for spherically symmetric space-times in the vacuum. This effective model is derived by the use of the path integral method, previously employed in several models of Loop Quantum…

General Relativity and Quantum Cosmology · Physics 2026-05-21 Juan Carlos Del Águila , Hugo A. Morales

We consider quantum transition amplitudes, partition functions and observables for 3D spin foam models within $SU(2)$ quantum group deformation symmetry, where the deformation parameter is a complex fifth root of unity. By considering…

High Energy Physics - Theory · Physics 2022-01-13 Marcelo Amaral , Raymond Aschheim , Klee Irwin

We construct a canonical formulation of general relativity for the case of a timelike foliation of spacetime. The formulation possesses explicit covariance with respect to Lorentz transformations in the tangent space. Applying the loop…

General Relativity and Quantum Cosmology · Physics 2016-08-31 Sergei Alexandrov , Zoltan Kadar

The Coleman-Mandula (CM) theorem states that the Poincar\'e and internal symmetries of a Minkowski spacetime quantum field theory cannot combine nontrivially in an extended symmetry group. We establish an analogous result for quantum field…

Mathematical Physics · Physics 2017-08-02 Christopher J. Fewster

Based upon the holographic principle, Jacobson demonstrated that the spacetime can be viewed as a gas of atoms with a related entropy given by the Bekenstein-Hawking formula. Following this argument, Friedmann equations can be derived by…

General Relativity and Quantum Cosmology · Physics 2015-10-13 C. A. S. Silva

Polymer quantum mechanics has been studied as a simplified picture that reflects some of the key properties of Loop Quantum Gravity; however, while the fate of relativistic symmetries in Loop Quantum Gravity is still not established, it is…

General Relativity and Quantum Cosmology · Physics 2017-12-06 Giovanni Amelino-Camelia , Michele Arzano , Malú Maira Da Silva , Daniel H. Orozco-Borunda