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This work applies the principles of quantum cosmology to examine models incorporating a quintom field. Specifically, three distinct models are analyzed: a simplified toy model, a model featuring an exponential quintom potential, and one…

General Relativity and Quantum Cosmology · Physics 2025-07-22 Behzad Tajahmad

We derive a semi-classical nonequilibrium work identity by applying the Wigner-Weyl quantization scheme to the Jarzynski identity for a classical Hamiltonian. This allows us, to the leading order in $\hbar$, to overcome the problem of…

Quantum Physics · Physics 2020-09-25 O. Brodier , K. Mallick , A. M. Ozorio de Almeida

The flat, homogeneous, and isotropic universe with a massless scalar field is a paradigmatic model in Loop Quantum Cosmology. In spite of the prominent role that the model has played in the development of this branch of physics, there still…

General Relativity and Quantum Cosmology · Physics 2010-09-23 Mercedes Martin-Benito , Guillermo A. Mena Marugan , Javier Olmedo

Recently, Falomir, Gamboa, Mendez, Gondolo and Maldonado proposed a bicosmology scenario [1-4] for solving some cosmological problems related to inflation, dark matter, and thermal history of the universe. Their plan is to introduce…

General Relativity and Quantum Cosmology · Physics 2022-12-27 Nahomi Kan , Takuma Aoyama , Kiyoshi Shiraishi

General analytical solutions of the Quantum Hamilton Jacobi Equation for conservative one-dimensional or reducible motion are presented and discussed. The quantum Hamilton's characteristic function and its derivative, i.e. the quantum…

Quantum Physics · Physics 2015-12-07 Mario Fusco Girard

Relativistic dynamics with energy and momentum resricted to an anti-de-Sitter space is presented, specifically in the introduction of coordiate operators conjugate to such momenta. Definition of functions of these operators, their…

High Energy Physics - Theory · Physics 2011-03-28 Myron Bander

The Wigner time delay, defined by the energy derivative of the total scattering phase shift, is an important spectral measure of an open quantum system characterising the duration of the scattering event. It is related to the trace of the…

Chaotic Dynamics · Physics 2014-12-12 Jack Kuipers , Dmitry V. Savin , Martin Sieber

Quantization in the minisuperspace of non minimal scalar-tensor theories leads to a partial differential equation which is non separable. Through a conformal transformation we can recast the Wheeler-DeWitt equation in an integrable form,…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Julio C. Fabris , Nelson Pinto-Neto , A. F. Velasco

[Shortened abstract:] In this thesis we investigate a solution to the `problem of time' in canonical quantum gravity by splitting spacetime into surfaces of constant mean curvature parameterised by York time. We argue that there are reasons…

General Relativity and Quantum Cosmology · Physics 2016-09-14 Philipp Roser

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

The paper addresses the quantization of minisuperspace cosmological models, with application to the Taub Model. By desparametrizing the model with an extrinsic time, a formalism is developed in order to define a conserved Schr\"{o}dinger…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Gabriel Catren , Rafael Ferraro

The Wheeler-DeWitt (WDW) equation is analyzed using two boundary proposals: the Hartle-Hawking no-boundary condition and tunneling condition. By compactifying the scale factor $a$ into $ x = a/(1+a) $, we reformulate the WDW equation to…

General Relativity and Quantum Cosmology · Physics 2025-03-28 Jie Jiang , Deog Ki Hong , Dong-han Yeom

We study the classical and quantum models of a scalar field Friedmann-Robertson-Walker (FRW) cosmology with an eye to the issue of time problem in quantum cosmology. We introduce a canonical transformation on the scalar field sector of the…

General Relativity and Quantum Cosmology · Physics 2015-06-11 Babak Vakili

We discuss the derivation of the so-called semi-classical equations for both mini-superspace and dilaton gravity. We find that there is no systematic derivation of a semi-classical theory in which quantum mechanics is formulated in a…

General Relativity and Quantum Cosmology · Physics 2010-11-01 S. P. de Alwis , D. A. MacIntire

The quantum cosmological version of a nonsingular Universe presented by Mukhanov and Brandenberger in the early nineties has been developed and the Hamilton Jacobi equation has been found under semiclassical (WKB) approximation. It has been…

General Relativity and Quantum Cosmology · Physics 2010-01-11 Abhik Kumar Sanyal

We present a phase-space noncommutative version of quantum mechanics and apply this extension to Quantum Cosmology. We motivate this type of noncommutative algebra through the gravitational quantum well (GQW) where the noncommutativity…

High Energy Physics - Theory · Physics 2015-05-13 Catarina Bastos , Orfeu Bertolami , Nuno Dias , Joao Nuno Prata

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

I apply the preceding paper's semiclassical treatment to geometrodynamics. The analogy between the two papers is quite useful at the level of the quadratic constraints, while I document the differences between the two due to the underlying…

General Relativity and Quantum Cosmology · Physics 2010-10-27 Edward Anderson

Semiclassical techniques have proven to be a very powerful method to extract physical effects from different quantum theories. Therefore, it is expected that in the near future they will play a very prominent role in the context of quantum…

General Relativity and Quantum Cosmology · Physics 2014-12-17 David Brizuela

We study the quantum cosmology of a quadratic $f(R)$ theory with a FRW metric, via one of its equivalent Horndeski type actions, where the dynamics of the scalar field is induced. The classical equations of motion and the Weeler-deWitt…

General Relativity and Quantum Cosmology · Physics 2017-06-22 V. Vázquez-Báez , C. Ramírez