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

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In this paper, we study implications of the geometrical nature of space- time for some of the basic tenets of quantum mechanics. That is, we study two different implications of the principle of general covariance; first we quantize a…

General Relativity and Quantum Cosmology · Physics 2013-05-16 Johan Noldus

As time passes, once simple quantum states tend to become more complex. For strongly coupled k-local Hamiltonians, this growth of computational complexity has been conjectured to follow a distinctive and universal pattern. In this paper we…

High Energy Physics - Theory · Physics 2017-02-28 Adam R. Brown , Leonard Susskind , Ying Zhao

We develop a dynamical framework for quantum measurement based on stochastic but unitary evolution in projective state space. Random Hamiltonians drawn from the Gaussian Unitary Ensemble generate stochastic unitary dynamics of the quantum…

Quantum Physics · Physics 2026-01-27 Alexey A. Kryukov

In its canonical formulation, general relativity is subject to gauge transformations that are equivalent to space-time coordinate changes of general covariance only when the gauge generators, given by the Hamiltonian and diffeomorphism…

General Relativity and Quantum Cosmology · Physics 2023-10-31 Martin Bojowald , Erick I. Duque

The dynamics of time-dependent coupled oscillator model for the charged particle motion subjected to a time-dependent external magnetic field is investigated. We used canonical transformation approach for the classical treatment of the…

Quantum Physics · Physics 2015-05-20 Salah Menouar , Mustapha Maamache , Jeong Ryeol Choi

In this second part of the `essay on the completion of quantum theory' we define the {\em unitary setting of completed quantum mechanics}, by adding as intrinsic data to those from Part I (arXiv:1711.08643) the choice of a north pole N and…

Mathematical Physics · Physics 2018-07-13 Wolfgang Bertram

We study the classical and quantum models of a flat Friedmann-Robertson-Walker (FRW) space-time, coupled to a perfect fluid, in the context of the consensus and a gauge-fixed Lagrangian frameworks. It is shown that, either in the usual or…

General Relativity and Quantum Cosmology · Physics 2015-03-19 Babak Vakili

We examine the dependence of quantization on global properties of a classical system. Quantization based on local properties may lead to ambiguities and inconsistency between local and global symmetries of a quantum system. Our quantization…

Astrophysics · Physics 2009-11-07 Wlodzimierz Piechocki

We consider a toy model of the interaction of a qubit with an exotic space-time containing a time-like curve. Consistency seems to require that the global evolution of the qubit be non-unitary. Given that quantum mechanics is globally…

Quantum Physics · Physics 2008-11-26 T. C. Ralph

The canonical quantum theory of a free field using arbitrary foliations of a flat two-dimensional spacetime is investigated. It is shown that dynamical evolution along arbitrary spacelike foliations is unitarily implemented on the same Fock…

High Energy Physics - Theory · Physics 2009-10-30 C. G. Torre , M. Varadarajan

Quantum field theory in curved spacetimes suffers in general from an infinite ambiguity in the choice of Fock representation and associated vacuum. In cosmological backgrounds, the requirement of a unitary implementation of the field…

High Energy Physics - Theory · Physics 2020-04-20 Luis J. Garay , Alberto García Martín-Caro , Mercedes Martín-Benito

We show that the real massive Klein-Gordon theory admits a description in terms of states on various timelike hypersurfaces and amplitudes associated to regions bounded by them. This realizes crucial elements of the general boundary…

High Energy Physics - Theory · Physics 2008-11-26 Robert Oeckl

In this paper, the generic part of the gauge theory of gravity is derived, based merely on the action principle and on the general principle of relativity. We apply the canonical transformation framework to formulate geometrodynamics as a…

General Relativity and Quantum Cosmology · Physics 2026-01-01 J. Struckmeier , J. Muench , D. Vasak , J. Kirsch , M. Hanauske , H. Stoecker

Our main goal in this paper is to extend to any system of coupled quadratic Hamiltonians some properties known for systems of quantum harmonic oscillators related with the Brownian Quantum Motion model. In a first part we get a rather…

Mathematical Physics · Physics 2012-11-19 Didier Robert

In this paper, we present a variational treatment of the linear dependence for a non-orthogonal time-dependent basis set in solving the Schr\"odinger equation. The method is based on: i) the definition of a linearly independent working…

Quantum Physics · Physics 2022-10-12 Loïc Joubert-Doriol

The quantum space-time model which accounts material Reference Frames (RF) quantum effects considered for flat space-time and ADM canonical gravity. As was shown by Aharonov for RF - free material object its c.m. nonrelativistic motion in…

High Energy Physics - Theory · Physics 2007-05-23 S. Mayburov

The subject of this paper is the consecutive procedure of discretization and quantization of two similar classical integrable systems in three-dimensional space-time: the standard three-wave equations and less known modified three-wave…

Exactly Solvable and Integrable Systems · Physics 2009-11-13 S. Sergeev

Dealing with a generic time-local non-Markovian master equation, we define current and power to be process-dependent as in classical thermodynamics. Each process is characterized by a symmetry transformation, a gauge of the master equation,…

Quantum Physics · Physics 2023-08-01 Fernando Nicacio , Raphael N. P. Maia

A midi-superspace model is a field theory obtained by symmetry reduction of a parent gravitational theory. Such models have proven useful for exploring the classical and quantum dynamics of the gravitational field. I present 3 recent…

General Relativity and Quantum Cosmology · Physics 2011-04-15 C. G. Torre

The purpose of this paper is to analyze in detail the Hamiltonian formulation for the compact Gowdy models coupled to massless scalar fields as a necessary first step towards their quantization. We will pay special attention to the coupling…

General Relativity and Quantum Cosmology · Physics 2008-11-26 J. Fernando Barbero G. , Daniel Gómez Vergel , Eduardo J. S. Villaseñor