Results 21 to 30 of about 536 (174)
A model of quantum gravity with emergent spacetime
Journal of High Energy Physics, 2020 We construct a model of quantum gravity in which dimension, topology and geometry of spacetime are dynamical. The microscopic degree of freedom is a real rectangular matrix whose rows label internal flavours, and columns label spatial sites. In the limit
Sung-Sik Lee
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Model for Emergence of Spacetime from Fluctuations
Physical Review Letters, 2023 We use a result of Hawking and Gilkey to define a Euclidean path integral of gravity and matter which has the special property of being independent of the choice of basis in the space of fields. This property allows the path integral to also describe physical regimes that do not admit position bases. These physical regimes are pregeometric in the sense
Marcus Reitz, Barbara Šoda, Achim Kempf
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A Historical Defence of Non-Spacetime Hypotheses: Non-Local Beables and Leibnizian Ubeity
Philosophia Scientiæ, 2016 Do theories of quantum mechanics and quantum gravity require spacetime to be a basic ground-level feature, or can spacetime be seen as an emergent element of these theories?
Edward Slowik
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How Nonassociative Geometry Describes a Discrete Spacetime
Frontiers in Physics, 2019 Nonassociative geometry, providing a unified description of discrete and continuum spaces, is a valuable candidate for the study of discrete models of spacetime. Within the framework of nonassociative geometry we propose a model of emergent spacetime. In
Alexander I. Nesterov, Héctor Mata
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Coherence and emergence of classical spacetime [PDF]
Physical Review D, 1997 Using the coherent-state representation we show that the classical Einstein equation for the FRW cosmological model with a general minimal scalar field can be derived from the semiclassical quantum Einstein equation.
Kim, Sang Pyo +3 more
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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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Time Travelling in Emergent Spacetime [PDF]
, 2021 Most approaches to quantum gravity suggest that relativistic spacetime is not fundamental, but instead emerges from some non-spatiotemporal structure. This paper investigates the implications of this suggestion for the possibility of time travel in the sense of the existence of closed timelike curves in some relativistic spacetimes.
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Entwinement and the emergence of spacetime [PDF]
Journal of High Energy Physics, 2015 It is conventional to study the entanglement between spatial regions of a quantum field theory. However, in some systems entanglement can be dominated by "internal", possibly gauged, degrees of freedom that are not spatially organized, and that can give rise to gaps smaller than the inverse size of the system.
Balasubramanian, V. +3 more
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Boltzmann Entropy, the Holographic Bound and Newtonian Cosmology
Proceedings, 2017 The holographic principle sets an upper bound on the total (Boltzmann) entropy content of the Universe at around 10 123 k B ( k B being Boltzmann’s constant).
Pedro Fernández De Córdoba +1 more
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Cosmological Particle Production in Quantum Gravity
Universe, 2021 Quantum theory of a test field on a quantum cosmological spacetime may be viewed as a theory of the test field on an emergent classical background.
Yaser Tavakoli
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