English
Related papers

Related papers: Is limiting curvature mimetic gravity an effective…

200 papers

Considering as usual that the underlying geometry of our universe is well described by the spatially flat Friedmann-Lemaitre-Robertson-Walker line element, we review how the background of holonomy corrected Loop Quantum Cosmology (LQC)…

General Relativity and Quantum Cosmology · Physics 2019-05-01 Jaume de Haro , Llibert Aresté Saló , Supriya Pan

We revisit the non-singular black hole solution in (extended) mimetic gravity with a limiting curvature from a Hamiltonian point of view. We introduce a parameterization of the phase space which allows us to describe fully the Hamiltonian…

General Relativity and Quantum Cosmology · Physics 2018-06-13 Jibril Ben Achour , Frederic Lamy , Hongguang Liu , Karim Noui

We show that under certain technical assumptions, including the existence of a constant mean curvature (CMC) slice and strict positivity of the scalar field, general relativity conformally coupled to a scalar field can be quantised on a…

General Relativity and Quantum Cosmology · Physics 2013-04-25 Norbert Bodendorfer , Alexander Stottmeister , Andreas Thurn

The "improved dynamics" of loop quantum cosmology is extended to include anisotropies of the Bianchi I model. As in the isotropic case, a massless scalar field serves as a relational time parameter. However, the extension is non-trivial…

General Relativity and Quantum Cosmology · Physics 2010-04-14 Abhay Ashtekar , Edward Wilson-Ewing

This papers offers a critical discussion on the procedure by which Loop Quantum Cosmology (LQC) is constructed from the full Loop Quantum Gravity (LQG) theory. Revising recent issues in preserving SU(2) symmetry when quantizing the…

General Relativity and Quantum Cosmology · Physics 2015-06-03 Francesco Cianfrani , Giovanni Montani

We present a new cosmological model derived from Loop Quantum Gravity. The formulation is based on a projection of the kinematical Hilbert space of the full theory down to a subspace representing the proper arena for an inhomogeneous…

General Relativity and Quantum Cosmology · Physics 2015-06-11 Emanuele Alesci , Francesco Cianfrani

We introduce a new framework for loop quantum gravity: mimicking the spinfoam quantization procedure we propose to study the symmetric sectors of the theory imposing the reduction weakly on the full kinematical Hilbert space of the…

General Relativity and Quantum Cosmology · Physics 2015-06-12 Emanuele Alesci , Francesco Cianfrani

The concept of effective dynamics has proven successful in LQC, a loop-inspired quantization of cosmological spacetimes. We apply the same idea of its derivation in LQC to the full theory, by computing the expectation value of the scalar…

General Relativity and Quantum Cosmology · Physics 2018-09-17 Andrea Dapor , Klaus Liegener

One of the qualitatively distinct and robust implication of Loop Quantum Gravity (LQG) is the underlying discrete structure. In the cosmological context elucidated by Loop Quantum Cosmology (LQC), this is manifested by the Hamiltonian…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Kinjal Banerjee , Ghanashyam Date

The framework of quantum symmetry reduction is applied to loop quantum gravity with respect to transitively acting symmetry groups. This allows to test loop quantum gravity in a large class of minisuperspaces and to investigate its features…

General Relativity and Quantum Cosmology · Physics 2010-11-19 Martin Bojowald

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

A one-parameter deformation of Einstein?Hilbert gravity with an inverse Riemann curvature term is derived as the classical limit of quantum gravity compatible with an accelerating universe. This result is based on the investigation of…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Frederic P. Schuller , Mattias N. R. Wohlfarth

We propose a quantum symmetry reduction of loop quantum gravity to Bianchi I spacetimes. To this end, we choose the diagonal metric gauge for the spatial diffeomorphism constraint at the classical level, leading to an…

General Relativity and Quantum Cosmology · Physics 2015-04-16 Norbert Bodendorfer

Certain versions of mimetic gravity have recently been claimed to present potential covariant theories of canonically modified spherically symmetric gravity, motivated by ingredients from loop quantum gravity. If such an equivalence were to…

General Relativity and Quantum Cosmology · Physics 2024-04-22 Martin Bojowald , Erick I. Duque

Over the last two years, the canonical approach to quantum gravity based on connections and triads has been put on a firm mathematical footing through the development and application of a new functional calculus on the space of gauge…

High Energy Physics - Theory · Physics 2015-06-26 Abhay Ashtekar

We discuss the semiclassical limit of Quantum Reduced Loop Gravity, a recently proposed model to address the quantum dynamics of the early Universe. We apply the techniques developed in full Loop Quantum Gravity to define the semiclassical…

General Relativity and Quantum Cosmology · Physics 2015-06-18 Emanuele Alesci , Francesco Cianfrani

In the framework of loop quantum cosmology anomaly free quantizations of the Hamiltonian constraint for Bianchi class A, locally rotationally symmetric and isotropic models are given. Basic ideas of the construction in (non-symmetric) loop…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Martin Bojowald

Polymer models are effective in describing quantum gravity effects around the initial singularity, leading to its replacement by bouncing surfaces on which the curvature and densities are finite. Their properties depend on the space-time…

General Relativity and Quantum Cosmology · Physics 2026-02-23 D. A. Cook , A. Olimpieri , I. P. R. Baranov , H. A. Borges , S. Carneiro

We discuss mimetic gravity theories with direct couplings between the curvature and higher derivatives of the scalar field, up to the quintic order, which were proposed to solve the instability problem for linear perturbations around the…

General Relativity and Quantum Cosmology · Physics 2019-12-18 Alexander Ganz , Nicola Bartolo , Sabino Matarrese

The use of non-regular representations of the Heisenberg-Weyl commutation relations has proved to be useful for studying conceptual and technical issues in quantum gravity. Of particular relevance is the study of Loop Quantum Cosmology…

General Relativity and Quantum Cosmology · Physics 2011-04-11 Alejandro Corichi , Tatjana Vukasinac , Jose A. Zapata
‹ Prev 1 2 3 10 Next ›