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Related papers: Nonlocal Effects in Quantum Gravity

200 papers

In loop quantum cosmology, non-perturbative quantum gravity effects lead to the resolution of the big bang singularity by a quantum bounce without introducing any new degrees of freedom. Though fundamentally discrete, the theory admits a…

General Relativity and Quantum Cosmology · Physics 2010-05-12 Gonzalo J. Olmo , Parampreet Singh

Based on empirical evidence, quantum systems appear to be strictly linear and gauge invariant. This work uses concise mathematics to show that quantum eigenvalue equations on a one dimensional ring can either be gauge invariant or have a…

Quantum Physics · Physics 2014-07-15 Arthur Davidson

It is shown that if a metric in quantum gravity can be decomposed as a sum of classical and quantum parts then Einstein quantum gravity looks approximately like modified gravity with a nonminimal interaction between gravity and matter.

General Relativity and Quantum Cosmology · Physics 2014-02-07 Vladimir Dzhunushaliev , Vladimir Folomeev , Burkhard Kleihaus , Jutta Kunz

Using a novel approach, we work out the general relativistic effects on the quantum interference of de Broglie waves associated with thermal neutrons. The unified general formula is consistent with special relativistic results in the flat…

General Relativity and Quantum Cosmology · Physics 2009-11-07 K. K. Nandi , Yuan-Zhong Zhang

Semi-classical gravity is an approximation to quantum gravity where gravity is treated classically and matter quantum mechanically. Matter is described by quantum field theory on curved space-time, whereas gravity is described by a…

General Relativity and Quantum Cosmology · Physics 2019-02-07 Ward Struyve

When attempting to assess the strengths and weaknesses of various principles in their potential role of guiding the formulation of a theory of quantum gravity, it is crucial to distinguish between principles which are strongly supported by…

History and Philosophy of Physics · Physics 2014-01-03 M. Holman

Time reversal symmetry is a fundamental property of many quantum mechanical systems. The relation between statistical physics and time reversal is subtle and not all statistical theories conserve this particular symmetry, most notably…

Strongly Correlated Electrons · Physics 2017-08-02 Miriam Scharnke , Niclas Schlünzen , Michael Bonitz

Quantum-gravity renders the space-time dimension to depend on the size of region; it monotonically increases with the size of region and asymptotically approaches four for large distances. This effect was discovered in numerical simulations…

High Energy Physics - Theory · Physics 2010-02-17 Michael Maziashvili

The paper argues that far from challenging - or even refuting - Bohm's quantum theory, the no-hidden-variables theorems in fact support the Bohmian ontology for quantum mechanics. The reason is that (i) all measurements come down to…

Quantum Physics · Physics 2018-07-04 Dustin Lazarovici , Andrea Oldofredi , Michael A. Esfeld

Any metric theory of gravity whose interaction with quantum particles is described by a covariant wave equation is equivalent to a vector theory that satisfies Maxwell-type equations identically. This result does not depend on any…

General Relativity and Quantum Cosmology · Physics 2014-04-30 Giorgio Papini

One of the leading issues in quantum field theory and cosmology is the mismatch between the observed and calculated values for the cosmological constant in Einstein's field equations of up to 120 orders of magnitude. In this paper, we…

General Relativity and Quantum Cosmology · Physics 2023-09-21 Michael Bishop , Peter Martin , Douglas Singleton

Despite the fact that quantum gravity is non-renormalisable, a consistent and mathematically rigorous construction of a perturbation series is possible. This is based on the use of the Batalin-Vilkovisky-Becchi-Rouet-Stora-Tyutin formalism…

General Relativity and Quantum Cosmology · Physics 2022-12-26 Romeo Brunetti , Klaus Fredenhagen , Kasia Rejzner

In its canonical formulation, general relativity is subject to gauge transformations that are equivalent to space-time coordinate changes of general covariance only when the gauge generators, given by the Hamiltonian and diffeomorphism…

General Relativity and Quantum Cosmology · Physics 2023-10-31 Martin Bojowald , Erick I. Duque

This is a self-contained introduction to quantum Riemannian geometry based on quantum groups as frame groups, and its proposed role in quantum gravity. Much of the article is about the generalisation of classical Riemannian geometry that…

High Energy Physics - Theory · Physics 2007-05-23 S. Majid

Well-known to specialists but little-known to the wider audience is that Newtonian gravity can be understood as geodesic motion in space-time, where time is absolute and space is Euclidean. Newtonian cosmology formulated by Heckmann agrees…

Classical Physics · Physics 2016-09-08 J. L. McCauley

We construct the covariant nonlocal action for recently suggested long-distance modifications of gravity theory motivated by the cosmological constant and cosmological acceleration problems. This construction is based on the special…

High Energy Physics - Theory · Physics 2007-05-23 A. O. Barvinsky

In canonical quantum gravity the wave function of the universe is static, leading to the so-called problem of time. We summarize here how Bohmian mechanics solves this problem.

General Relativity and Quantum Cosmology · Physics 2023-07-18 Ward Struyve

We consider nonlocal modified Einstein gravity without matter, where nonlocal term has the form $P(R) F(\Box) Q(R)$. For this model, in this paper we give the derivation of the equations of motion in detail. This is not an easy task and…

High Energy Physics - Theory · Physics 2019-02-26 Ivan Dimitrijevic , Branko Dragovich , Zoran Rakic , Jelena Stankovic

The appearance of Hamiltonian constraint in the canonical formalism for general relativity reflects the lack of a fixed external time. The dynamics of general relativistic systems can be expressed with respect to an arbitrarily chosen…

General Relativity and Quantum Cosmology · Physics 2017-09-21 Przemyslaw Malkiewicz

Taking quantum physics as well as large scale astronomical observations into account, a spacetime metric is introduced, such that the nonlinear part of the Einstein tensor contains effects of the order of Planck's constant.

General Relativity and Quantum Cosmology · Physics 2015-06-25 J. Lamey , G. M. Obermair