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Related papers: The structure of cosmic time

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In the early seventies, Alan Sandage defined cosmology as the search for two numbers: Hubble parameter ${{H}_{0}}$ and deceleration parameter ${{q}_{0}}$. The first of the two basic cosmological parameters (the Hubble parameter) describes…

General Relativity and Quantum Cosmology · Physics 2015-02-04 Yu. L. Bolotin , V. A. Cherkaskiy , O. A. Lemets , D. A. Yerokhin , L. G. Zazunov

We pursue the view that quantum theory may be an emergent structure related to large space-time scales. In particular, we consider classical Hamiltonian systems in which the intrinsic proper time evolution parameter is related through a…

General Relativity and Quantum Cosmology · Physics 2014-11-17 Hans-Thomas Elze

A new dynamical paradigm merging quantum dynamics with cosmology is discussed. Time evolution involves a genuine passage of time, which distinguishes the formalism from those where dynamics in space is equivalent to statics in space-time.…

General Physics · Physics 2024-02-01 Marek Czachor

In a previous paper we proposed a new approach to the beginning of inflation -- a lingering universe. The universe begins in a lingering state with a nearly vanishing Hubble parameter. This calls into question the absolute age of the…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-09 Brandon Melcher , Arnab Pradhan , Scott Watson

We show that within the cosmology associated with conformal gravity the age of the universe is given as $1/H_0$, to thus overcome the current cosmological age crisis. We show that while the parameter $\Omega_{mat} = \rho_{mat} / \rho_C$…

Astrophysics · Physics 2007-05-23 Philip D. Mannheim

In the standard cosmological theory one uses the Einstein concepts of space and time as were originally introduced for the special theory of relativity and the general relativity theory. According to this approach all physical quantities…

Astrophysics · Physics 2007-05-23 Moshe Carmeli

The nature of time vis-a-vis relativity is critically examined. Based on the author's space-time interaction hypothesis of late 1970's, cosmological model with time-varying velocity of light is discussed.

General Relativity and Quantum Cosmology · Physics 2007-05-23 S. C. Tiwari

The discovery that the Universe is accelerating in its expansion has brought the basic concept of cosmic expansion into question. An analysis of the evolution of this concept suggests that the paradigm that was finally settled into prior to…

History and Philosophy of Physics · Physics 2014-09-12 Daryl Janzen

In the early seventies, Alan Sandage defined cosmology as the search for two numbers: Hubble parameter ${{H}_{0}}$ and deceleration parameter ${{q}_{0}}$. The first of the two basic cosmological parameters (the Hubble parameter) describes…

General Relativity and Quantum Cosmology · Physics 2015-07-01 Yu. L. Bolotin , V. A. Cherkaskiy , O. A. Lemets , D. A. Yerokhin , L. G. Zazunov

Existing accounts of the cosmological arrow of time face a dilemma: generalist approaches that posit time-asymmetric laws lack independent motivation, while particularist approaches that invoke a Past Hypothesis face serious conceptual and…

History and Philosophy of Physics · Physics 2025-10-06 Sean Gryb , Simon Friederich

By including appropriate Riemman cubic invariants, we find that the dynamics of classical time crystals can be straightforwardly realized in Einstein gravity on the FLRW metric. The time reflection symmetry is spontaneously broken in the…

High Energy Physics - Theory · Physics 2020-11-25 Xing-Hui Feng , Hyat Huang , Shou-Long Li , H. Lu , Hao Wei

Barrow, and Barrow and collaborators, have put forward theoretical models with variable fundamental constants including JBD theories. The experimental evidence for an accelerating Universe points out to a deceleration parameter…

General Relativity and Quantum Cosmology · Physics 2009-09-23 Marcelo Samuel Berman , Luis A. Trevisan

The role of global topology in the dynamics of the Universe is poorly understood. Along with observational programmes for determining the topology of the Universe, some small theoretical steps have recently been made. Heuristic…

General Physics · Physics 2015-06-03 Boudewijn F. Roukema

We consider a novel model of cosmic inflation. In our model one does not need any specific matter field to drive inflation, but inflation stems from the microscopic, Planck scale structure of spacetime, thus being of quantum gravitational…

General Relativity and Quantum Cosmology · Physics 2014-08-28 Jarmo Mäkelä

We investigate the role of the cosmological constant in the holographic description of a radiation-dominated universe $C_2/R^4$ with a positive cosmological constant $\Lambda$. In order to understand the nature of cosmological term, we…

High Energy Physics - Theory · Physics 2010-04-05 Y. S. Myung

Collapse models possibly suggest the need for a better understanding of the structure of space-time. We argue that physical space, and space-time, are emergent features of the Universe, which arise as a result of dynamical collapse of the…

Quantum Physics · Physics 2017-02-01 Tejinder P. Singh

There are theories which implement the idea that the constants of nature may be "time dependent." These introduce new fields representing "evolving constants," in addition to physical fields. We argue that dynamical matter coupling…

General Relativity and Quantum Cosmology · Physics 2018-07-27 Syed Moeez Hassan , Viqar Husain , Babar Qureshi

I describe an approach which connects classical gravity with the quantum microstructure of spacetime. The field equations arise from maximizing the density of states of matter plus geometry. The former is identified using the thermodynamics…

General Relativity and Quantum Cosmology · Physics 2017-08-25 T. Padmanabhan

The standard model of modern cosmology, which is based on the Friedmann-Lema\^itre-Robertson-Walker metric, allows the definition of an absolute time. However, there exist (cosmological) models consistent with the theory of general…

General Relativity and Quantum Cosmology · Physics 2013-03-20 Michael Buser , Endre Kajari , Wolfgang P. Schleich

Recent advances in observational cosmology are changing the way we view the nature of time. In general relativity, the freedom in choosing a time hypersurface has hampered the implementation of the theory. Fortunately, Hamilton-Jacobi…

Astrophysics · Physics 2007-05-23 D. S. Salopek
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