English
Related papers

Related papers: Quantum Gowdy $T^3$ model: A unitary description

200 papers

We study scalar fields subject to an equation of the Klein-Gordon type in nonstationary spacetimes, such as those found in cosmology, assuming that all the relevant spatial dependence is contained in the Laplacian. We show that the field…

General Relativity and Quantum Cosmology · Physics 2015-06-19 Laura Castelló Gomar , Guillermo A. Mena Marugán

This paper is the first of two papers devoted to formulation of quantum mechanics of a particle in a normal geodesic frame of reference in the general Riemannian space-time. Here canonical quantization of geodesic motion in the…

General Relativity and Quantum Cosmology · Physics 2007-05-23 E. A. Tagirov

We study a pair of canonoid (fouled) Hamiltonians of the harmonic oscillator which provide, at the classical level, the same equation of motion as the conventional Hamiltonian. These Hamiltonians, say $K_{1}$ and $K_{2}$, result to be…

Quantum Physics · Physics 2015-06-26 P. Tempesta , E. Alfinito , R. A. Leo , G. Soliani

Canonical quantization of spherically symmetric space-times is carried out, using real-valued densitized triads and extrinsic curvature components, with specific factor ordering choices ensuring in an anomaly free quantum constraint…

General Relativity and Quantum Cosmology · Physics 2015-06-05 Suddhasattwa Brahma

Quantum canonical transformations corresponding to time-dependent diffeomorphisms of the configuration space are studied. A special class of these transformations which correspond to time-dependent dilatations is used to identify a…

Quantum Physics · Physics 2008-11-26 Ali Mostafazadeh

It has recently been shown that the classical electric and magnetic fields which satisfy the source-free Maxwell equations can be linearly mapped into the real and imaginary parts of a transverse-vector wave function which in consequence…

General Physics · Physics 2010-12-24 Steven Kenneth Kauffmann

We formulate the quantum mechanics of the solutions of a Klein-Gordon-type field equation: (\partial_t^2+D)\psi(t)=0, where D is a positive-definite operator acting in a Hilbert space \tilde H. We determine all the positive-definite inner…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Ali Mostafazadeh

We study the evolution of a quantum scalar field in a toy universe which has three stages of evolution, viz., (i) an early (inflationary) de Sitter phase (ii) radiation dominated phase and (iii) late-time (cosmological constant dominated)…

General Relativity and Quantum Cosmology · Physics 2013-12-12 Suprit Singh , Sujoy Kumar Modak , T. Padmanabhan

The canonical quantization of the tachyon field is suggested. Quantization is based on the conception of stable and unstable components of the tachyon degrees of freedom.

High Energy Physics - Phenomenology · Physics 2012-02-14 G. V. Efimov

We review an approach to non-commutative geometry, where models are constructed by quantisation of the coordinates. In particular we focus on the full DFR model and its irreducible components; the (arbitrary) restriction to a particular…

Mathematical Physics · Physics 2010-09-24 Gherardo Piacitelli

We present a quantum geometric framework for stochastic quantisation in the case of a free Klein-Gordon field on Euclidean space. In this approach the noise is part of the background space, spacetime is fuzzy. We extend the notion of sharp…

High Energy Physics - Theory · Physics 2015-06-26 F. Vanderseypen

We quantize a homogeneous and isotropic universe for two models of modified teleparallel gravity, wherein an arbitrary function of the boundary term, namely $B$, is present in the action and in the other model a scalar field that is…

General Relativity and Quantum Cosmology · Physics 2024-05-07 H. Amiri , K. Atazadeh , H. Hadi

Quantum field theory in curved space-times is a well developed area in mathematical physics which has had important phenomenological applications to the very early universe. However, it is not commonly appreciated that on time dependent…

General Relativity and Quantum Cosmology · Physics 2015-07-27 Ivan Agullo , Abhay Ashtekar

On the path towards quantum gravity, we find friction between temporal relations in quantum mechanics (QM) (where they are fixed and field-independent), and in general relativity (where they are field-dependent and dynamic). This paper aims…

General Relativity and Quantum Cosmology · Physics 2017-11-28 Henrique Gomes

By considering (non-relativistic) quantum mechanics as it is done in practice in particular in condensed-matter physics, it is argued that a deterministic, unitary time evolution within a chosen Hilbert space always has a limited scope,…

Quantum Physics · Physics 2017-10-03 Barbara Drossel

Can certain degrees of freedom of a closed physical system, described by a time-independent Hamiltonian, become more and more classical as they evolve from some state? This question is important because our universe seems to have done just…

General Relativity and Quantum Cosmology · Physics 2015-01-26 Kinjalk Lochan , Krishnamohan Parattu , T. Padmanabhan

We consider the Hamiltonian dynamics of spherically symmetric Einstein gravity with a thin null-dust shell, under boundary conditions that fix the evolution of the spatial hypersurfaces at the two asymptotically flat infinities of a…

General Relativity and Quantum Cosmology · Physics 2016-08-25 Jorma Louko , Bernard F. Whiting , John L. Friedman

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

Quantum computation with quantum data that can traverse closed timelike curves represents a new physical model of computation. We argue that a model of quantum computation in the presence of closed timelike curves can be formulated which…

Quantum Physics · Physics 2008-11-26 Dave Bacon

In this paper, we investigate the quantum field theory in Klein space that has two time directions. To study the canonical quantization, we select the ``length of time" $q$ as the evolution direction of the system. In our novel…

High Energy Physics - Theory · Physics 2026-04-07 Bin Chen , Zezhou Hu , Xin-Cheng Mao