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In general relativity, the Einstein equations provide spherically symmetric static spacetimes with dynamics defined as an evolution along the radial coordinate $r$. The geometrical sector becomes a one-dimensional mechanical system, with…

General Relativity and Quantum Cosmology · Physics 2025-11-03 Etera R. Livine , Yuki Yokokura

So far, none of attempts to quantize gravity has led to a satisfactory model that not only describe gravity in the realm of a quantum world, but also its relation to elementary particles and other fundamental forces. Here, we outline the…

General Relativity and Quantum Cosmology · Physics 2021-11-29 Houri Ziaeepour

Gravitomagnetic equations result from applying quaternionic differential operators to the energy-momentum tensor. These equations are similar to the Maxwell's EM equations. Both sets of the equations are isomorphic after changing…

General Relativity and Quantum Cosmology · Physics 2019-02-21 Valeriy I. Sbitnev

A precise interpretation of the Universe wave function is forbidden in the spirit of the Copenhagen School since a precise notion of measure operation cannot be satisfactorily defined. Here we propose a Bohmian interpretation of the…

General Relativity and Quantum Cosmology · Physics 2024-07-04 Giulia Maniccia , Giovanni Montani

We discuss how the classical notions of time and causal structure may emerge together with quantum-mechanical probabilities from a universal quantum state. For this, the process of decoherence between semiclassical branches is important.…

General Relativity and Quantum Cosmology · Physics 2025-06-24 Leonardo Chataignier , Claus Kiefer , Mritunjay Tyagi

In this paper, a new Hamiltonian constraint operator for loop quantum cosmology is constructed by using the Chern-Simons action. The quantum dynamics of the $k=0$ cosmological model with respect to a massless scalar field as an emergent…

General Relativity and Quantum Cosmology · Physics 2019-09-23 Jinsong Yang , Cong Zhang , Yongge Ma

We derive an effective gravitational potential, induced by the quantum wavefunction of a physical vacuum of a self-gravitating configuration, while the vacuum itself is viewed as the superfluid described by the logarithmic quantum wave…

General Relativity and Quantum Cosmology · Physics 2020-12-01 Konstantin G. Zloshchastiev

Generalized Fourier transformation between the position and the momentum representation of a quantum state is constructed in a coordinate independent way. The only ingredient of this construction is the symplectic (canonical) geometry of…

Quantum Physics · Physics 2012-03-14 Witold Chmielowiec , Jerzy Kijowski

We study the back-reaction of quantum systems onto classical ones. Taking the starting point that semi-classical physics should be described at all times by a point in classical phase space and a quantum state in Hilbert space, we consider…

Quantum Physics · Physics 2024-12-18 Isaac Layton , Jonathan Oppenheim , Zachary Weller-Davies

The probability representation for quantum states of the universe in which the states are described by a fair probability distribution instead of wave function (or density matrix) is developed to consider cosmological dynamics. The…

General Relativity and Quantum Cosmology · Physics 2015-06-25 V. I. Man'ko , G. Marmo , C. Stornaiolo

We start from classical Hamiltonian constraint of general relativity to obtain the Einstein-Hamiltonian-Jacobi equation. We obtain a time parameter prescription demanding that geometry itself determines the time, not the matter field, such…

General Relativity and Quantum Cosmology · Physics 2015-06-25 S. Biswas , A. Shaw , B. Modak , D. Biswas

The global dynamics of a homogeneous universe in Loop Quantum Cosmology is viewed as a scattering process of its geometrodynamical equivalent. This picture is applied to build a flexible (easy to generalize) and not restricted just to…

General Relativity and Quantum Cosmology · Physics 2010-04-22 Wojciech Kaminski , Tomasz Pawlowski

The exact solution of the Hamiltonian constraint in canonical gravity and the resultant reduction of Einstein's theory reveal the synergy between gravitation and the intrinsic cosmic clock of our expanding universe. Intrinsic Time…

General Relativity and Quantum Cosmology · Physics 2023-11-27 Chopin Soo

It has earlier been argued that there should exist a formulation of quantum mechanics which does not refer to a background spacetime. In this paper we propose that, for a relativistic particle, such a formulation is provided by a…

General Relativity and Quantum Cosmology · Physics 2007-05-23 T. P. Singh

We study the potential effects of spacetime non-metricity in cosmology. In the spirit of Einstein-Cartan gravity, but with non-metricity replacing torsion, we consider the Einstein-Hilbert action and assume zero torsion. Adopting certain…

General Relativity and Quantum Cosmology · Physics 2023-03-29 Damianos Iosifidis , Ioannis Georgios Vogiatzis , Christos G. Tsagas

Quantum theory expresses the observable relations between physical properties in terms of probabilities that depend on the specific context described by the "state" of a system. However, the laws of physics that emerge at the macroscopic…

Quantum Physics · Physics 2016-06-06 Holger F. Hofmann

In the present paper we generalize the original work of C.W. Misner \cite{M69q} about the quantum dynamics of the Bianchi type IX geometry near the cosmological singularity. We extend the analysis to the generic inhomogeneous universe by…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Giovanni Imponente , Giovanni Montani

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 present a theory of discontinuous motion of particles in continuous space-time. We show that the simplest nonrelativistic evolution equation of such motion is just the Schroedinger equation in quantum mechanics. This strongly implies…

Quantum Physics · Physics 2007-05-23 Rui Qi

The hilbert-space structure of quantum mechanics is related to the causal structure of space-time. The usual measurement hypotheses apparently preclude nonlinear or stochastic quantum evolution. By admitting a difference in the calculus of…

Quantum Physics · Physics 2007-05-23 George Svetlichny