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Related papers: Probing spacetime foam with extragalactic sources

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Ultralight dark matter induces time-dependent perturbations in the spacetime metric, enabling its gravitational direct detection. In this work, we propose using astrometry to detect dark matter. After reviewing the calculation of the metric…

High Energy Physics - Phenomenology · Physics 2025-08-06 Jeff A. Dror , Sarunas Verner

The interferometry-based experimental tests of quantum properties of space-time which the author sketched out in a recent short Letter [Nature 398 (1999) 216] are here discussed in self-contained fashion. Besides providing detailed…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Giovanni Amelino-Camelia

Quantum technologies are opening novel avenues for applied and fundamental science at an impressive pace. In this perspective article, we focus on the promises coming from the combination of quantum technologies and space science to test…

In the context of a model of space-time foam, made by $N$ wormholes we discuss the possibility of having a foam formed by different configurations. An equivalence between Schwarzschild and Schwarzschild-Anti-de Sitter wormholes in terms of…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Remo Garattini

A simple model of spacetime foam, made by $N$ Reissner-Nordstr\"{o}m wormholes with a magnetic and electric charge in a semiclassical approximation, is taken under examination. The Casimir-like energy of the quantum fluctuation of such a…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Remo Garattini

We conjecture that the neutral black hole pair production is related to the vacuum fluctuation of pure gravity via the Casimir-like energy. Implications on the foam-like structure of spacetime are discussed.

General Relativity and Quantum Cosmology · Physics 2009-10-31 Remo Garattini

We re-examine the brick-wall model in the context of spacetime foam. In particular we consider a foam composed by wormholes of different sizes filling the black hole horizon. The contribution of such wormholes is computed via a scale…

General Relativity and Quantum Cosmology · Physics 2016-12-21 Remo Garattini

I consider the possibility that space experiments be used to search for quantum properties of spacetime. On the basis of recent quantum-gravity results, I argue that insight on some quantum properties of spacetime can be obtained with…

Astrophysics · Physics 2009-11-10 Giovanni Amelino-Camelia

New quantum degrees of freedom of space-time, originating at the Planck scale, could create a coherent indeterminacy and noise in the transverse position of massive bodies on macroscopic scales. An experiment is under development at…

General Relativity and Quantum Cosmology · Physics 2013-07-18 Craig Hogan

The current understanding of dark matter comes largely from measurements of the total matter content in the universe, from the distribution of gravitating matter on very large scales, and from rotation curves and velocity dispersions on…

In cosmology it has become usual to introduce new entities as dark matter and dark energy in order to explain otherwise unexplained observational facts. Here, we propose a different approach treating spacetime as a continuum endowed with…

General Relativity and Quantum Cosmology · Physics 2008-11-26 A. Tartaglia , M. Capone

Astronomical observations strongly suggest that our universe is now accelerating and contains a substantial admixture of dark vacuum energy. Using numerical simulations to study this newly consolidated cosmological model (with a constant…

Astrophysics · Physics 2009-11-10 Fred C. Adams , Michael T. Busha , August E. Evrard , Risa H. Wechsler

In a D-brane model of space-time foam, there are contributions to the dark energy that depend on the D-brane velocities and on the density of D-particle defects. The latter may also reduce the speeds of photons linearly with their energies,…

Cosmology and Nongalactic Astrophysics · Physics 2011-05-25 John Ellis , Nick E. Mavromatos , Dimitri V. Nanopoulos

The evolution of a global monopole with an inflating core is investigated. An analytic expression for the exterior metric at large distances from the core is obtained. The overall spacetime structure is studied numerically, both in vacuum…

General Relativity and Quantum Cosmology · Physics 2009-10-30 Inyong Cho , Alexander Vilenkin

Simple models of a classical spacetime foam are considered, which consist of identical static defects embedded in Minkowski spacetime. Plane-wave solutions of the vacuum Maxwell equations with appropriate boundary conditions at the defect…

High Energy Physics - Phenomenology · Physics 2008-11-26 S. Bernadotte , F. R. Klinkhamer

Gamma-ray bursts and ultra-high-energy cosmic rays provide an important testing ground for fundamental physics. A simple-minded analysis of some gamma-ray bursts would lead to a huge estimate of the overall energy emitted, and this…

High Energy Physics - Phenomenology · Physics 2015-06-25 Giovanni Amelino-Camelia

An interferometric technique is proposed for determining the spatial forms of the individual degrees of freedom through which a many body system can absorb energy from its environment. The method separates out the coherent excitations…

Quantum Physics · Physics 2017-08-30 S. Withington , C. N. Thomas , D. J. Goldie

In this whitepaper, we outline how recent technological advances and ongoing developments open qualitatively new science opportunities in cosmology, fundamental physics, and quantum astrophysics. First, intensity interferometry can…

Recently a stochastic underpinning for space time has been considered, what may be called Quantized Fractal Space Time. This leads us to a number of very interesting consequences which are testable, and also provides a rationale for several…

General Physics · Physics 2017-02-08 B. G. Sidharth

Any slight variations in the fundamental constants of Nature, which may be induced by dark matter or some yet-to-be-discovered cosmic field, would characteristically alter the phase of a light beam inside an interferometer, which can be…

High Energy Physics - Phenomenology · Physics 2015-04-24 Y. V. Stadnik , V. V. Flambaum
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