English
Related papers

Related papers: The problem of time in quantum cosmology

200 papers

In this topical review we discuss the connections between chaos, decoherence and quantum cosmology. We understand chaos as classical chaos in systems with a finite number of degrees of freedom, decoherence as environment induced decoherence…

General Relativity and Quantum Cosmology · Physics 2015-06-05 Esteban Calzetta

Quantum--mechanical operators corresponding to canonical momentum and position of a point--like particle, which follow from the quantum field theory in the general Riemannian space-time, satisfy generally to a deformation of the canonical…

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

The understanding of time and dynamics can be elucidated by examining the concept of entanglement in quantum theory. This particular perspective on time is referred to as the timeless approach, which posits that the universe exists in a…

General Relativity and Quantum Cosmology · Physics 2023-12-07 H. Hadi , F. Darabi , K. Atazadeh

We critically discuss the measure of very short time intervals. By means of a "gedankenexperiment", we describe an ideal clock based on the occurrence of completely random events. We show that the minimum time interval Delta t that this…

General Relativity and Quantum Cosmology · Physics 2016-03-23 Luciano Burderi , Tiziana Di Salvo

We investigate aspects of quantum cosmology in relation to string cosmology systems that are described in terms of the Dirac-Born-Infeld action. Using the Silverstein-Tong model, we analyze the Wheeler-DeWitt equation for the rolling scalar…

High Energy Physics - Theory · Physics 2009-11-11 Anastasios Psinas

We write down a quantum gravity equation which generalizes the Wheeler-DeWitt one in view of including a time dependence in the wave functional. The obtained equation provides a consistent canonical quantization of the 3-geometries…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Giovanni Montani

There are a number of problematic features within the current treatment of time in physical theories, including the "timelessness" of the Universe as encapsulated by the Wheeler-DeWitt equation. This paper considers one particular…

Quantum Physics · Physics 2018-01-17 K. L. H. Bryan , A. J. M. Medved

If time has three dimensions, how does a particle move? This paper demonstrates that quantum physics naturally emerges from a framework of three-dimensional time. We present the equations governing the motion of 0-spin, 1-spin, and 1/2-spin…

Quantum Physics · Physics 2024-08-21 Xiaodong Chen

The problem of time in quantum mechanics concerns the fact that in the Schr\"odinger equation time is a parameter, not an operator. Pauli's objection to a time-energy uncertainty relation analogue to the position-momentum one, conjectured…

Quantum Physics · Physics 2017-04-05 M. Bauer

Loop quantum cosmology of the k=0 FRW model (with a massless scalar field) is shown to be exactly soluble if the scalar field is used as the internal time already in the classical Hamiltonian theory. Analytical methods are then used i) to…

General Relativity and Quantum Cosmology · Physics 2010-04-23 Abhay Ashtekar , Alejandro Corichi , Parampreet Singh

We elaborate on a proposal made by Greensite and others to solve the problem of time in quantum gravity. The proposal states that a viable concept of time and a sensible inner product can be found from the demand for the Ehrenfest equations…

General Relativity and Quantum Cosmology · Physics 2009-10-28 T. Brotz , C. Kiefer

We study the Stephani quantum cosmological model in the presence of a cosmological constant in radiation dominated Universe. In the present work the Schutz's variational formalism which recovers the notion of time is applied. This gives…

General Relativity and Quantum Cosmology · Physics 2008-11-26 P. Pedram , S. Jalalzadeh , S. S. Gousheh

The time-of-arrival problem asks for the probability distribution for when a quantum particle reaches a specified location. It has been the subject of decades of debate, exemplifying the lack of a self-adjoint time observable in quantum…

Quantum Physics · Physics 2026-04-02 Niyusha Hosseini , Maximilian P. E. Lock

Quantum mechanics in its presently known formulation requires an external classical time for its description. A classical spacetime manifold and a classical spacetime metric are produced by classical matter fields. In the absence of such…

General Relativity and Quantum Cosmology · Physics 2008-11-26 T. P. Singh

We analize the relational quantum evolution of generally covariant systems in terms of Rovelli's evolving constants of motion and the generalized Heisenberg picture. In order to have a well defined evolution, and a consistent quantum…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Rodolfo Gambini , Rafael A. Porto

A class of $k$-Essence cosmological models, with a power law kinetic term, is quantised in the mini-superspace. It is shown that for a specific configuration, corresponding to a pressureless fluid, a Schr\"odinger-type equation is obtained…

General Relativity and Quantum Cosmology · Physics 2016-12-28 C. R. Almeida , J. C. Fabris , F. Sbisá , Y. Tavakoli

We replace the usual Hamiltonian constraint of quantum gravity H|psi>=0 by a weaker one <psi|H|psi>=0. This allows |psi> to satisfy the time-dependent functional Schrodinger equation. In general, only the phase of the wave function appears…

General Relativity and Quantum Cosmology · Physics 2007-05-23 H. Nikolic

We study longstanding problem of cosmological clock in the context of Brans-Dicke theory of gravitation. We present the Hamiltonian formulation of the theory for a class of spatially homogenous cosmological models. Then, we show that…

General Relativity and Quantum Cosmology · Physics 2011-06-09 Hossein Farajollahi , Mehrdad Farhoudi , Hossein Shojaie

Equations of motion for single particle under two proper time model and three proper time model have been proposed and analyzed. The motions of particle are derived from pure classical method but they exhibit the same properties of quantum…

Quantum Physics · Physics 2007-05-23 xiaodong Chen

The purpose of this paper is to introduce a new way to inquire the quantum cosmology for a certain gravitational theory. Normally, the quantum cosmological model is introduced as the minisuperspace theory which is obtained by reducing the…

General Relativity and Quantum Cosmology · Physics 2016-06-07 Miao He , Zi-Liang Wang , Jian-Bo Deng , Hua Chen
‹ Prev 1 8 9 10 Next ›