Results 11 to 20 of about 51,631 (191)
Living Reviews in Relativity, 2008 Quantum gravity is expected to be necessary in order to understand situations in which classical general relativity breaks down. In particular in cosmology one has to deal with initial singularities, i.e., the fact that the backward evolution of a ...
Bojowald Martin
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Living Reviews in Relativity, 2005 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 of a classical
Bojowald Martin
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Switching Internal Times and a New Perspective on the `Wave Function of the Universe’
Universe, 2019 Despite its importance in general relativity, a quantum notion of general covariance has not yet been established in quantum gravity and cosmology, where, given the a priori absence of coordinates, it is necessary to replace classical frames with ...
Philipp A. Höhn
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Does a Theory of Everything Exist?
Философия и космология, 2021 Since Einstein’s failure to define a Grand Unified Theory, physicists have pursued a comprehensive theory explaining nature, a Theory of Everything. But because General Relativity, Quantum Field Theory, and Cosmology have little in common, defining one ...
James R Johnson
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Black Hole Thermodynamics [PDF]
, 2014 The discovery in the early 1970s that black holes radiate as black bodies has radically affected our understanding of general relativity, and offered us some early hints about the nature of quantum gravity.
Carlip, S.
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Einstein and Rastall theories of gravitation in comparison
European Physical Journal C: Particles and Fields, 2018 We profit by a recent paper of Visser claiming that Rastall gravity is equivalent to Einstein gravity to compare the two gravitational theories in a general way. Our conclusions are different from Visser’s ones.
F. Darabi +4 more
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$$f(\mathcal {G})$$ f(G) Noether cosmology
European Physical Journal C: Particles and Fields, 2020 We develop the n-dimensional cosmology for $$f(\mathcal {G})$$ f(G) gravity, where $$\mathcal {G}$$ G is the Gauss–Bonnet topological invariant. Specifically, by the so-called Noether Symmetry Approach, we select $$f(\mathcal {G})\simeq \mathcal {G}^k ...
Francesco Bajardi, Salvatore Capozziello
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DeWitt boundary condition is consistent in Hořava-Lifshitz quantum gravity
Physics Letters B, 2022 In quantum cosmology the DeWitt boundary condition is a proposal to set the wave function of the universe to vanish at the classical big-bang singularity.
Hiroki Matsui +2 more
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Braneworlds and Quantum States of Relativistic Shells [PDF]
, 2007 We review some applications of relativistic shells that are relevant in the context of quantum gravity/quantum cosmology. Using a recently developed approach, the stationary states of this general relativistic system can be determined in the ...
Ansoldi, Stefano
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Making Classical and Quantum Canonical General Relativity Computable through a Power Series Expansion in the Inverse Cosmological Constant [PDF]
Physical Review Letters, 2000 5 pages, RevTeX with multicol and ...
Gambini, Rodolfo, Pullin, Jorge
openaire +3 more sources