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Related papers: Radiation-Dominated Quantum Friedmann Models

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We perform a minisuperspace analysis of an information-theoretic nonlinear Wheeler-deWitt (WDW) equation for de Sitter universes. The nonlinear WDW equation, which is in the form of a difference-differential equation, is transformed into a…

General Relativity and Quantum Cosmology · Physics 2012-04-02 Rajesh R. Parwani , Siti Nursaba Tarih

We present a systematic analysis of the dynamics of flat Friedmann-Lema\^{i}tre-Robertson-Walker cosmological models with radiation and dust matter in generalized teleparallel $f(T)$ gravity. We show that the cosmological dynamics of this…

General Relativity and Quantum Cosmology · Physics 2017-09-05 Manuel Hohmann , Laur Jarv , Ulbossyn Ualikhanova

There is a common expectation that the big-bang singularity must be resolved in quantum gravity but it is not clear how this can be achieved. A major obstacle here is the difficulty of interpreting wave-functions in quantum gravity. The…

General Relativity and Quantum Cosmology · Physics 2023-11-07 Ali Kaya

Several proposals to deal with the dynamics of general relativity involve gauge fixings or the introduction matter fields in terms of which the theory is deparameterized. The resulting theories have true Hamiltonians for their evolution…

General Relativity and Quantum Cosmology · Physics 2013-05-30 Rodolfo Gambini , Jorge Pullin

In this work we study the birth of Friedmann-Lema\^{\i}tre-Robertson-Walker (FLRW) models with zero ($k=0$) and negative ($k=-1$) curvatures of the spatial sections. The material content of the models is composed of a radiation perfect…

General Relativity and Quantum Cosmology · Physics 2023-01-13 G. Oliveira-Neto , D. L. Canedo , G. A. Monerat

We describe how physical universes that are composed of gauge and gravitationally interacting bosonic and fermionic quantum fields arise from the generic discrete distribution of many quantifiable properties of arbitrary static entities.…

General Physics · Physics 2018-08-17 Sergei Bashinsky

We shall revisit the conventional treatment of open quantum devices based on the Wigner-Function formalism. Our analysis will show that the artificial spatial separation between device active region and external reservoirs -properly defined…

Other Condensed Matter · Physics 2007-05-23 Luigi Genovese , David Taj , Fausto Rossi

We compute effective equations of the quantum FRW flat universe in the radiation dominated era at $\hbar$ order, described in terms of Ashtekar variables employing a new method for the geometrical formulation of quantum mechanics.…

General Relativity and Quantum Cosmology · Physics 2017-01-03 Aureliano Skirzewski , Jesus Rodriguez

In a recent paper [Phys. Rev. D 92:084012, 2015], the author studied the classical $(1+1)$-dimensional Friedmann-Robertson-Walker (FRW) universe filled with a perfect fluid in Ho\v{r}ava-Lifshitz (HL) theory of gravity. This theory is…

General Relativity and Quantum Cosmology · Physics 2016-05-25 J. P. M. Pitelli

In this work the homogeneous and isotropic Universe of Friedmann-Robertson-Walker is studied in the presence of two fluids: stiff matter and radiation described by the Schutz's formalism. We obtain to the classic case the behaviour of the…

General Relativity and Quantum Cosmology · Physics 2017-10-18 F. G. Alvarenga , R. Fracalossi , R. C. Freitas , S. V. B. Gonçalves

We propose a version of the non-relativistic quantum mechanics in which the pure states of a quantum system are described as sections of a Hilbert (generally infinitely-dimensional) fibre bundle over the space-time. There evolution is…

Quantum Physics · Physics 2008-11-26 Bozhidar Z. Iliev

To admit a canonically conjugate time operator, the Hamiltonian has to be a generator of translations (like the momentum operator generates translations in space), so its spectrum must be unbounded. But the Hamiltonian governing our world…

Quantum Physics · Physics 2024-09-02 Ovidiu Cristinel Stoica

In this work, we use an extension of the quantization condition, given in Ref. [1], to numerically explore the finite-volume spectrum of three relativistic particles, in the case that two-particle subsets are either resonant or bound. The…

High Energy Physics - Lattice · Physics 2019-10-17 Fernando Romero-López , Stephen R. Sharpe , Tyler D. Blanton , Raúl A. Briceño , Maxwell T. Hansen

The formation of bound states involving multiple particles underlies many interesting quantum physical phenomena, such as Efimov physics or superconductivity. In this work we show the existence of an infinite number of such states for some…

Quantum Physics · Physics 2016-06-01 Tao Shi , Ying-Hai Wu , A. Gonzalez-Tudela , J. I. Cirac

In this paper we study the quantum cosmology of homogeneous and isotropic cosmology, via the Weyl-Wigner-Groenewold-Moyal formalism of phase space quantization, with perfect fluid as a matter source. The corresponding quantum cosmology is…

General Relativity and Quantum Cosmology · Physics 2017-01-25 M. Rashki , S. Jalalzadeh

Any two infinite-dimensional (separable) Hilbert spaces are unitarily isomorphic. The sets of all their self-adjoint operators are also therefore unitarily equivalent. Thus if all self-adjoint operators can be observed, and if there is no…

Quantum Physics · Physics 2008-02-03 A. P. Balachandran

In this work we study the existence of mechanisms of transition to global chaos in a closed Friedmann-Robertson-Walker universe with a massive conformally coupled scalar field. We propose a complexification of the radius of the universe so…

General Relativity and Quantum Cosmology · Physics 2009-11-10 S. E. Jorás , T. J. Stuchi

The spinning electromagnetic universe, known also as the Rotating Bertotti-Robinson(RBR) spacetime is considered as a model to represent our cosmos. The model derives from different physical considerations, such as colliding waves, throat…

General Relativity and Quantum Cosmology · Physics 2025-02-07 M. Halilsoy , V. Memari

We consider space-times with two isometries which represent gravitational waves with distinct wavefronts which propagate into exact Friedmann-Robertson-Walker (FRW) universes. The geometry of possible wavefronts is analysed in detail in all…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Jiri Bicak , Jerry B. Griffiths

This study explores the age-old quest to construct a geometric model of a quantum particle. While static classical particle models have largely been dismissed, the focus has now shifted to intricate dynamic models that hold the promise of…

General Relativity and Quantum Cosmology · Physics 2024-05-21 Michael Cramer Andersen