Results 21 to 30 of about 20,723 (77)
Loop quantum gravity corrections to gravitational wave dispersion [PDF]
, 1997 Cosmological tensor perturbations equations are derived for Hamiltonian cosmology based on Ashtekar's formulation of general relativity, including typical quantum gravity effects in the Hamiltonian constraint as they are expected from loop quantum ...
Bojowald, Martin, Hossain, Golam Mortuza
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Relational Motivation for Conformal Operator Ordering in Quantum Cosmology
, 2009 Operator-ordering in quantum cosmology is a major as-yet unsettled ambiguity with not only formal but also physical consequences. We determine the Lagrangian origin of the conformal invariance that underlies the conformal operator-ordering choice in ...
Anderson, Edward
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, 2003 The observable universe could be a 1+3-surface (the "brane") embedded in a 1+3+d-dimensional spacetime (the "bulk"), with standard-model particles and fields trapped on the brane while gravity is free to access the bulk.
Maartens, Roy
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, 2005 An almost brief, though lengthy, review introduction about the long history of higher order gravities and their applications, as employed in the literature, is provided.
A. Mardones +55 more
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Beables/Observables in Classical and Quantum Gravity [PDF]
, 2014 Observables 'are observed' whereas beables just 'are'. This gives beables more scope in the cosmological and quantum domains. Both observables and beables are entities that form 'brackets' with 'the constraints' that are 'equal to' zero.
Anderson, Edward
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Coherent states for FLRW space-times in loop quantum gravity
, 2011 We construct a class of coherent spin-network states that capture proprieties of curved space-times of the Friedmann-Lama\^itre-Robertson-Walker type on which they are peaked.
Abhay Ashtekar +7 more
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Evolution of Primordial Black Holes in Loop Quantum Gravity
, 2011 In this work, we study the evolution of Primordial Black Holes within the context of Loop Quantum Gravity. First we calculate the scale factor and energy density of the universe for different cosmic era and then taking these as inputs we study evolution ...
B. Nayak +4 more
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The present moment in quantum cosmology: challenges to the arguments for the elimination of time [PDF]
, 2000 Barbour, Hawking, Misner and others have argued that time cannot play an essential role in the formulation of a quantum theory of cosmology. Here we present three challenges to their arguments, taken from works and remarks by Kauffman, Markopoulou and ...
Smolin, Lee
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Some implications of signature-change in cosmological models of loop quantum gravity
, 2015 Signature change at high density has been obtained as a possible consequence of deformed space-time structures in models of loop quantum gravity. This article provides a conceptual discussion of implications for cosmological scenarios, based on an ...
Bojowald, Martin, Mielczarek, Jakub
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Non-polynomial Lagrangian approach to Regular Black Holes
, 2017 We present a review on Lagrangian models admitting spherically symmetric regular black holes, and cosmological bounce solutions. Non-linear electrodynamics, non-polynomial gravity, and fluid approaches are explained in details.
Chinaglia, Stefano +2 more
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