Phantom singularities and their quantum fate: general relativity and beyond—a CANTATA COST action topic [PDF]
General Relativity and Gravitation, 2019 Cosmological observations allow the possibility that dark energy is caused by phantom fields. These fields typically lead to the occurrence of singularities in the late Universe.
Mariam Bouhmadi-L'opez +2 more
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Review of: "Quantum Cosmology: Cosmology directly linked to the Planck Scale in General Relativity Theory and Newton Gravity" [PDF]
Yohannes Yebabe Tesfay
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Conformal Cyclic Cosmology, gravitational entropy and quantum information
General Relativity and Gravitation, 2023 We inspect the basic ideas underlying Roger Penrose’s Conformal Cyclic Cosmology from the perspective of modern quantum information. We show that the assumed loss of degrees of freedom in black holes is not compatible with the quantum notion of entropy ...
Michał Eckstein
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On the propagation across the big bounce in an open quantum FLRW cosmology [PDF]
The European Physical Journal C, 2022 The propagation of a scalar field in an open FLRW bounce-type quantum spacetime is examined, which arises within the framework of the IKKT matrix theory.
E. Battista, H. Steinacker
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L'emergenza dello spazio-tempo nella gravità quantistica e nella cosmologia quantistica
Philosophy Kitchen, 2019 Our best description of spacetime is provided by general relativity – yet, this theory is not thought to be fundamental. Instead, it is expected to be replaced by a theory of quantum gravity, which may not feature spacetime fundamentally.
Karen Crowther
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Higher-dimensional view on quantum cosmology [PDF]
Physical Review D, 2021 We argue that the choice of boundary condition for the wave function in quantum cosmology depends on the UV completion of general relativity. We provide an explicit example using a braneworld scenario in which a de Sitter cosmology is induced on the ...
U. Danielsson +3 more
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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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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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