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Related papers: Quantum singularities in a solvable toy model

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It is shown that the initial conditions in the quasi-Heisenberg quantization scheme can be set at the initial cosmological singularity per se. This possibility is provided by finiteness of some quantities, namely momentums of the dynamical…

General Relativity and Quantum Cosmology · Physics 2017-08-01 S. L. Cherkas , V. L. Kalashnikov

Despite its great successes in accounting for the current observations, the so called `standard' model of cosmology faces a number of fundamental unresolved questions. Paramount among these are those relating to the nature of the origin of…

General Relativity and Quantum Cosmology · Physics 2008-02-29 Martin Bojowald , Reza Tavakol

Quantum particles can be obtained from a classical probability distribution in phase space by a suitable coarse graining, whereby simultaneous classical information about position and momentum can be lost. For a suitable time evolution of…

Quantum Physics · Physics 2015-05-18 C. Wetterich

The exactly solvable quantum model of the homogeneous, isotropic and closed universe in the matter-energy production epoch is considered. It is assumed that the universe is originally filled with a uniform scalar field and a perfect fluid…

General Relativity and Quantum Cosmology · Physics 2011-07-19 V. E. Kuzmichev , V. V. Kuzmichev

The degree of freedom of the scalar field in scalar-tensor gravity is employed as "time" to deparametrize the Hamiltonian constraint of the theory. The deparametrized system is then nonperturbatively quantized by the approach of loop…

General Relativity and Quantum Cosmology · Physics 2026-03-02 Faqiang Yuan , Haida Li , Shengzhi Li , Yongge Ma

Alternative scenarios to the Big Bang singularity have been subject of intense research for several decades by now. Most popular in this sense have been frameworks were such singularity is replaced by a bounce around some minimal…

General Relativity and Quantum Cosmology · Physics 2017-09-25 Emanuele Alesci , Gioele Botta , Francesco Cianfrani , Stefano Liberati

It is shown, that extended particle-like objects should infinitely long collapse into some discontinuous configurations of the same topology, but vanishing mass. Analytic results concerning the general properties and asymptotic rates of…

High Energy Physics - Theory · Physics 2007-05-23 K. Sveshnikov

During the past decade, the experimental development of being able to create ever larger and heavier quantum superpositions has brought the discussion of the connection between microscopic quantum mechanics and macroscopic classical physics…

Quantum Physics · Physics 2010-04-29 Jasper van Wezel

The subject of this study is Quantum and Statistical Mechanics of the Early Universe. In it a new approach to investigation of these two theories - density matrix deformation - is proposed. The distinguishing feature of the proposed…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Alex. E. Shalyt-Margolin

In quantum cosmology, one has to select a specific wave function solution of the quantum state equations under consideration in order to obtain concrete results. The simplest choices have been already explored, in different frameworks,…

General Relativity and Quantum Cosmology · Physics 2021-09-06 P. C. M. Delgado , N. Pinto-Neto

Loop quantum cosmology applies techniques derived for a background independent quantization of general relativity to cosmological situations and draws conclusions for the very early universe. Direct implications for the singularity problem…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Martin Bojowald

Optical experiments designed to explore quantum complementarity are reanalyzed. It is argued that, for each, a classical explanation is not only possible, but more coherent and less contrived. The final conclusion is that these experiments…

Quantum Physics · Physics 2007-05-23 A. F. Kracklauer

Isotropic models in loop quantum cosmology allow explicit calculations, thanks largely to a completely known volume spectrum, which is exploited in order to write down the evolution equation in a discrete internal time. Because of genuinely…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Martin Bojowald

The two ways of constrained systems quantization are considered from the point of view of their self-consistency at the quantum level. With a transparent example of a particle in the external electromagnetic field we demonstrate that the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Yu. S. Kalashnikova , A. V. Nefediev

We apply the complex de Broglie-Bohm formulation of quantum mechanics [1] to a spatially closed homogeneous and isotropic early Universe whose matter content are radiation and dust perfect fluids. We then show that an expanding classical…

General Relativity and Quantum Cosmology · Physics 2016-10-12 M. Fathi , S. Jalalzadeh , P. V. Moniz

A self-contained discussion of nonrelativistic quantum scattering is presented in the case of central potentials in one space dimension, which will facilitate the understanding of the more complex scattering theory in two and three…

Quantum Physics · Physics 2009-11-06 Vania E. Barlette , Marcelo M. Leite , Sadhan K. Adhikari

We introduce the set of constraints the wave function of the Universe has to satisfy in order to describe an Universe undergoing through the process of spontaneous breaking of supersymmetry and discuss the way this may lead to the emergence…

General Relativity and Quantum Cosmology · Physics 2007-05-23 O. Bertolami , P. V. Moniz

We introduce a formulation of quantum theory (QT) as a general probabilistic theory but expressed via quasi-expectation operators (QEOs). This formulation provides a direct interpretation of density matrices as quasi-moment matrices. Using…

Quantum Physics · Physics 2022-03-10 Alessio Benavoli , Alessandro Facchini , Marco Zaffalon

Due to the accelerated expansion of the universe, the possibility of formation of singularities has changed from the classical Big Bang and Big Crunch singularities to include a number of new scenarios. In recent papers it has been shown…

General Relativity and Quantum Cosmology · Physics 2021-12-15 L. Fernández-Jambrina

We study a relation between the cosmological singularities in classical and quantum theory, comparing the classical and quantum dynamics in some models possessing the Big Brake singularity - the model based on a scalar field and two models…

General Relativity and Quantum Cosmology · Physics 2015-06-15 A. Kamenshchik , S. Manti