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Related papers: Cosmology within Noncommutative Spectral Geometry

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New Planck scale physics may solve the singularity problems of classical general relativity and may lead to interesting consequences for very early Universe cosmology. Two approaches to these questions are reviewed in this article. The…

General Relativity and Quantum Cosmology · Physics 2016-08-31 Robert H. Brandenberger

We provide detailed evidence for the claim that nonperturbative quantum gravity, defined through state sums of causal triangulated geometries, possesses a large-scale limit in which the dimension of spacetime is four and the dynamics of the…

High Energy Physics - Theory · Physics 2010-04-06 J. Ambjorn , J. Jurkiewicz , R. Loll

It is first argued that radiation by a uniformly accelerated charge in flat space-time indicates the need for a unified geometric theory of gravity and electromagnetism. Such a theory, based on a metric-affine $U_4$ manifold, is constructed…

General Physics · Physics 2018-08-30 Partha Ghose

Quantum theory is formulated as a probabilistic theory on a flat Minkowski space-time, while general theory of relativity is formulated on a curved manifold as a geometric theory. Bohmian Quantum Gravity approach indicates that one need to…

General Physics · Physics 2018-10-31 Sijo K. Joseph

Astrophysical observations provide a picture of the universe as a 4-dim homogeneous and isotropic flat space-time dominated by an unknown form of dark energy. To achieve such a cosmology one has to consider in the early universe an…

Astrophysics · Physics 2009-11-10 F. Canfora , A. Troisi

The cosmological scale factor $a(t)$ of the flat-space Robertson-Walker geometry is examined from a Hamiltonian perspective wherein $a(t)$ is interpreted as an independent dynamical coordinate and the curvature density $\sqrt {- g(a)}…

General Physics · Physics 2008-10-04 M. Ibison

The configuration space of general relativity is superspace - the space of all Riemannian 3-metrics modulo diffeomorphisms. However, it has been argued that the configuration space for gravity should be conformal superspace - the space of…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Bryan Kelleher

This paper proposes a method of unifying quantum mechanics and gravity based on quantum computation. In this theory, fundamental processes are described in terms of pairwise interactions between quantum degrees of freedom. The geometry of…

Quantum Physics · Physics 2018-04-11 Seth Lloyd

We investigate the quantum structure of spacetime at fundamental scales via a novel, Lorentz-invariant noncommutative coordinate framework. Building on insights from noncommutative geometry, spectral theory, and algebraic quantum field…

Mathematical Physics · Physics 2026-01-13 Markus B. Fröb , Albert Much , Kyriakos Papadopoulos

The quest for a quantum gravity phenomenology has inspired a quantum notion of space-time, which motivates us to study the fate of the relativistic symmetries of a particular model of quantum space-time, as well as its intimate connection…

High Energy Physics - Theory · Physics 2023-07-21 Partha Nandi , Anwesha Chakraborty , Sayan Kumar Pal , Biswajit Chakraborty , Frederik G Scholtz

I give a summary review of the research program using noncommutative geometry as a framework to determine the structure of space-time. Classification of finite noncommutative spaces under few assumptions reveals why nature chose the…

High Energy Physics - Theory · Physics 2019-02-25 Ali H. Chamseddine

Treating the gravitational force on the same footing as the electroweak and strong forces, we present a quantum field theory of gravity based on spin and scaling gauge symmetries. A biframe spacetime is initiated to describe such a quantum…

High Energy Physics - Theory · Physics 2016-01-20 Yue-Liang Wu

Familiar textbook quantum mechanics assumes a fixed background spacetime to define states on spacelike surfaces and their unitary evolution between them. Quantum theory has changed as our conceptions of space and time have evolved. But…

General Relativity and Quantum Cosmology · Physics 2008-06-09 James B. Hartle

We develop the spectral point of view on geometry based on the formalism of quantum physics. We start from the simple physical question of specifying our position in space and explain how the spectral geometric point of view provides a new…

High Energy Physics - Theory · Physics 2019-04-11 Ali H. Chamseddine , Alain Connes

A generalised equivalence principle is put forward according to which space-time symmetries and internal quantum symmetries are indistinguishable before symmetry breaking. Based on this principle, a higher-dimensional extension of Minkowski…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Dorje C. Brody , Lane P. Hughston

The cosmological constant problem can be understood as the failure of the decoupling principle behind effective field theory, so that some quantities in the low-energy theory are extremely sensitive to the high-energy properties. While this…

High Energy Physics - Theory · Physics 2015-12-01 Carlos Barceló , Raúl Carballo-Rubio , Luis J. Garay

It is shown that for Robertson-Walker models with flat or closed space sections, all of the cosmological spectral shift can be attributed to the non-flat connection (and thus indirectly to space-time curvature). For Robertson-Walker models…

General Physics · Physics 2013-03-29 Dag Østvang

A physical theory of the world is presented under the unifying principle that all of nature is laid out before us and experienced through the passage of time. The one-dimensional progression in time is opened out into a multi-dimensional…

General Physics · Physics 2016-07-01 David J. Jackson

Modelling structure formation across the full dynamical range of the Universe remains a major challenge in cosmology. This difficulty originates from a fundamental limitation of geodesics in general relativity: a one-parameter family of…

Cosmology and Nongalactic Astrophysics · Physics 2026-04-16 Obinna Umeh

A complete model of the universe needs at least three parts: (1) a complete set of physical variables and dynamical laws for them, (2) the correct solution of the dynamical laws, and (3) the connection with conscious experience. In quantum…

High Energy Physics - Theory · Physics 2007-05-23 Don N. Page
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