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Related papers: Quantum Foam

200 papers

An effective model for the spacetime foam is constructed in terms of nonlocal interactions in a classical background. In the weak-coupling approximation, the evolution of the low-energy density matrix is determined by a master equation that…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Luis J. Garay

On the quantum stage spacetime had the foam-like structure. When the Universe cools the foam structure temperes and therefore the Friedman model represents only the mean picture. We show that effects of the foamed structure we observe now…

Astrophysics · Physics 2007-05-23 A. A. Kirillov

We use two simple independent gedankan experiments to show that the holographic principle can be understood intuitively as having its origin in the quantum fluctuations of spacetime. Applied to cosmology, this consideration leads to a…

General Relativity and Quantum Cosmology · Physics 2017-06-28 Y. Jack Ng

Plausibly spacetime is "foamy" on small distance scales, due to quantum fluctuations. We elaborate on the proposal to detect spacetime foam by looking for seeing disks in the images of distant quasars and AGNs. This is a null test in the…

Cosmology and Nongalactic Astrophysics · Physics 2011-04-22 Wayne A. Christiansen , David J. E. Floyd , Y. Jack Ng , Eric S. Perlman

I propose a phenomenological description of space-time foam and discuss the experimental limits that are within reach of forthcoming experiments.

General Relativity and Quantum Cosmology · Physics 2014-11-17 Giovanni Amelino-Camelia

A simple model of spacetime foam, made by spherically symmetric wormholes, with or without a cosmological term is proposed. The black hole area quantization and its consequences are examined in this context. We open the possibility of…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Remo Garattini

On the quantum stage spacetime had the foam-like structure. When the Universe cools, the foam structure tempers and does not disappear. We show that effects caused by the foamed structure mimic very well the observed Dark Matter phenomena.…

Astrophysics · Physics 2008-11-26 A. A. Kirillov , D. Turaev

There are not many tools to quantitatively monitor the emergence of classical geometric features from a quantum spacetime, whose microscopic structure may be a highly quantum-fluctuating "spacetime foam". To improve this situation, we…

High Energy Physics - Theory · Physics 2023-05-10 R. Loll , A. Silva

We propose a formulation of the holographic principle, suitable for a background independent quantum theory of cosmology. It is stated as a relationship between the flow of quantum information and the causal structure of a quantum…

High Energy Physics - Theory · Physics 2007-05-23 Fotini Markopoulou , Lee Smolin

Astronomical observations of distant quasars may be important to test models for quantum gravity, which posit Planck-scale spatial uncertainties ('spacetime foam') that would produce phase fluctuations in the wavefront of radiation emitted…

Cosmology and Nongalactic Astrophysics · Physics 2016-07-29 Eric S. Perlman , Saul A. Rappaport , Y. Jack Ng , Wayne A. Christiansen , John DeVore , David Pooley

The concept of holography has lured philosophers of science for decades, and is becoming more and more popular on several fronts of science, e. g. in the physics of black holes. In this paper we try to understand things as if the visible…

Computational Physics · Physics 2007-05-23 Zoltan Batiz , Bhag C. Chauhan

More than 65 years ago, John Wheeler suggested that quantum uncertainties of the metric would be of order one at the Planck scale, leading to large fluctuations in spacetime geometry and topology, which he termed "spacetime foam." In this…

General Relativity and Quantum Cosmology · Physics 2023-05-17 S. Carlip

Quantum gravitational effects, on the one hand, lead to a limitation in the accuracy of measuring spatial and time intervals, and, on the other hand, they generate a discrete of spacetime structure (quantum foam). The common source of both…

General Relativity and Quantum Cosmology · Physics 2024-07-17 Yu. L. Bolotin , V. V. Yanovsky

Progress in the new information-theoretic process physics is reported in which the link to the phenomenology of general relativity is made. In process physics the fundamental assumption is that reality is to be modelled as self-organising…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Reginald T. Cahill

In this work, I review some aspects concerning the evolution of quantum low-energy fields in a foamlike spacetime, with involved topology at the Planck scale but with a smooth metric structure at large length scales, as follows. Quantum…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Luis J. Garay

Quantum diffusion describes the inflow of vacuum quantum fluctuations as they get amplified by gravitational instability, and stretched to large distances during inflation. In this picture, the dynamics of the universe's expansion becomes…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-12 Vincent Vennin , David Wands

The spin foam framework provides a way to define the dynamics of canonical loop quantum gravity in a spacetime covariant way, by using a path integral over histories of quantum states which can be interpreted as `quantum space-times'. This…

General Relativity and Quantum Cosmology · Physics 2015-06-15 Jonathan Engle

If spacetime undergoes quantum fluctuations, an electromagnetic wavefront will acquire uncertainties in direction as well as phase as it propagates through spacetime. These uncertainties can show up in interferometric observations of…

General Relativity and Quantum Cosmology · Physics 2016-11-15 Y. Jack Ng

A mathematical formalism for treating spacetime topology as a quantum observable is provided. We describe spacetime foam entirely in algebraic terms. To implement the correspondence principle we express the classical spacetime manifold of…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Ioannis Raptis , Roman R. Zapatrin

At Planck-scale, spacetime is "foamy" due to quantum fluctuations predicted by quantum gravity. Here we consider the possibility of using spacetime foam-induced phase incoherence of light from distant galaxies and gamma-ray bursters to…

Astrophysics · Physics 2009-11-07 Y. Jack Ng , W. A. Christiansen , H. van Dam