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Related papers: Ramifications of Non Commutative Spacetime

200 papers

The questions of what represents space-time in GR, the status of gravitational energy, the substantivalist-relationalist issue, and the (non)exceptional status of gravity are interrelated. If space-time has energy-momentum, then space-time…

History and Philosophy of Physics · Physics 2022-08-12 J. Brian Pitts

We study properties of a scalar quantum field theory on two-dimensional noncommutative space-times. Contrary to the common belief that noncommutativity of space-time would be a key to remove the ultraviolet divergences, we show that field…

High Energy Physics - Theory · Physics 2007-05-23 M. Chaichian , A. Demichev , P. Presnajder

We have recently introduced an approach for studying perturbatively classical and quantum canonical general relativity. The perturbative technique appears to preserve many of the attractive features of the non-perturbative quantization…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Rodolfo Gambini , Jorge Pullin

The contemporary physics has revealed growing evidences that the emergence can be applied to not only biology and condensed matter systems but also gravity and spacetime. We observe that noncommutative spacetime necessarily implies emergent…

High Energy Physics - Theory · Physics 2015-04-03 Hyun Seok Yang

In loop quantum cosmology, Friedmann-LeMaitre-Robertson-Walker (FLRW) space-times arise as well-defined approximations to specific \emph{quantum} geometries. We initiate the development of a quantum theory of test scalar fields on these…

General Relativity and Quantum Cosmology · Physics 2009-11-06 Abhay Ashtekar , Wojciech Kaminski , Jerzy Lewandowski

Spacetime emergence refers to the notion that classical spacetime "emerges" as an approximate macroscopic entity from a non-spatio-temporal structure present in a more complete theory of interacting fundamental constituents. In this…

High Energy Physics - Theory · Physics 2015-06-05 Chiu Man Ho , Thomas W. Kephart , Djordje Minic , Y. Jack Ng

The perturbative approach to quantum field theory using retarded functions is extended to noncommutative theories. Unitarity as well as quantized equations of motion are studied and seen to cause problems in the case of space-time…

High Energy Physics - Theory · Physics 2009-11-10 Tobias Reichenbach

Though Quantum SuperString Theory has shown promise, there are some puzzling features like the extra dimensions, which are curled up in the Kaluza-Klein sense. On the other hand a recent formulation of what may be called Quantized Fractal…

General Physics · Physics 2007-05-23 B. G. Sidharth

The idea that spacetime has to be replaced by Clifford space (C-space) is explored. Quantum field theory (QFT) and string theory are generalized to C-space. It is shown how one can solve the cosmological constant problem and formulate…

High Energy Physics - Theory · Physics 2009-11-11 Matej Pavsic

Recently, we presented a unified way of analysing classical cosmological perturbation in generalized gravity theories. In this paper, we derive the perturbation spectrums generated from quantum fluctuations again in unified forms. We…

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

The possibility has been recently demonstrated to manufacture (nonrelativistic, Hamiltonian) many-body problems which feature an isochronous time evolution with an arbitrarily assigned period $T$ yet mimic with good approximation, or even…

General Relativity and Quantum Cosmology · Physics 2015-08-11 Fabio Briscese , Francesco Calogero

It was recently suggested that the cosmological constant problem as viewed in a non-perturbative framework is intimately connected to the choice of time and a physical Hamiltonian. We develop this idea further by calculating the…

General Relativity and Quantum Cosmology · Physics 2018-04-05 Syed Moeez Hassan

In high-energy physics, coordinate noncommutativity represents the core idea that space itself can be quantized, as expressed through the frameworks of string theory and noncommutative field theory. Influence of such a noncommutativity on…

Quantum Physics · Physics 2025-04-22 Salim Medjber , Hacene Bekkar , Salah Menouar , Jeong Ryeol Choi

Classical limits of quantum systems are shown to lead to different conceptions of spaces different from the classical one underlying the process of quantization of such systems. The accent is put in situations where traces of…

Quantum Physics · Physics 2022-07-22 Thierry Paul

We study relativistic particle, string and membrane theories as defining field theories containing gravity in (0+1), (1+1) and (2+1) spacetime dimensions respectively. We show how an off shell invariance of the massless particle action…

High Energy Physics - Theory · Physics 2007-05-23 W. Chagas-Filho

Trying to connect a fundamentally non-commutative spacetime with the conservative perturbative approach to quantum gravity, we are led to the natural question: are non-commutative geometrical effects already present in the regime where…

General Relativity and Quantum Cosmology · Physics 2023-04-20 Markus Fröb , Albert Much , Kyriakos Papadopoulos

We introduce three space-times that are discrete in time and compatible with the Lorentz symmetry. We show that these spaces are no commutative, with commutation relations similar to the relations of the Snyder and Yang spaces. Furthermore,…

High Energy Physics - Theory · Physics 2008-11-26 Juan M. Romero , J. D. Vergara , J. A. Santiago

We show the existence of a noncommutative spacetime structure in the context of a complete discussion on the underlying spacetime symmetries for the physical system of a free massless relativistic particle. The above spacetime symmetry…

High Energy Physics - Theory · Physics 2009-11-10 R. P. Malik

We propose a variation of spacetime noncommutative field theory to realize the stringy spacetime uncertainty relation without breaking any of the global symmetries of the homogeneous isotropic universe. We study the spectrum of metric…

High Energy Physics - Theory · Physics 2009-11-07 Robert Brandenberger , Pei-Ming Ho

The structure and properties of possible $q$-Minkowski spaces is discussed, and the corresponding non-commutative differential calculi are developed in detail and compared with already existing proposals. This is done by stressing its…

High Energy Physics - Theory · Physics 2016-08-14 J. A. de Azcárraga , P. P. Kulish , F. Rodenas