English
Related papers

Related papers: Quantum Spin Dynamics (QSD)

200 papers

The absence of recognizable, low energy quantum gravitational effects requires that some asymptotic series expansion be wonderfully accurate, but the correct expansion might involve logarithms or fractional powers of Newton's constant. That…

General Relativity and Quantum Cosmology · Physics 2015-05-30 P. J. Mora , N. C. Tsamis , R. P. Woodard

The gravitational effects in the relativistic quantum mechanics are investigated. The exact Foldy-Wouthuysen transformation is constructed for the Dirac particle coupled to the static spacetime metric. As a direct application, we analyze…

General Relativity and Quantum Cosmology · Physics 2011-08-17 Yuri N. Obukhov

We summarize our recently proposed approach to quantum field theory on noncommutative curved spacetimes. We make use of the Drinfel'd twist deformed differential geometry of Julius Wess and his group in order to define an action functional…

High Energy Physics - Theory · Physics 2011-03-24 Alexander Schenkel

We present a theoretical framework for equilibrium and nonequilibrium dynamical simulation of quantum states with spin-density-wave (SDW) order. Within a semiclassical adiabatic approximation that retains electron degrees of freedom, we…

Strongly Correlated Electrons · Physics 2018-01-12 Gia-Wei Chern , Kipton Barros , Zhentao Wang , Hidemaro Suwa , Cristian D. Batista

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

A Wilson loop is defined, in 4-D pure Einstein gravity, as the trace of the holonomy of the Christoffel connection or of the spin connection, and its invariance under the symmetry transformations of the action is showed (diffeomorphisms and…

High Energy Physics - Theory · Physics 2009-10-22 Giovanni Modanese

A new functional calculus, developed recently for a fully non-perturbative treatment of quantum gravity, is used to begin a systematic construction of a quantum theory of geometry. Regulated operators corresponding to areas of 2-surfaces…

General Relativity and Quantum Cosmology · Physics 2010-04-06 Abhay Ashtekar , Jerzy Lewandowski

The asymptotic structure of three-dimensional higher-spin anti-de Sitter gravity is analyzed in the metric approach, in which the fields are described by completely symmetric tensors and the dynamics is determined by the standard…

High Energy Physics - Theory · Physics 2015-03-03 Andrea Campoleoni , Marc Henneaux

Quantum fields are shown to provide an example of infinite-dimensional quantum groups. A dictionary is established between quantum field and quantum group concepts: the expectation value over the vacuum is the counit, Wick's theorem is the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Christian Brouder , Robert Oeckl

In Foldy-Wouthuysen representation, we deduce the effective quantum mechanics for a particle confined to a curved surface by using the thin-layer quantization scheme. We find that the spin effect caused by confined potential as the results…

Quantum Physics · Physics 2022-06-08 Hao Zhao , Yong-Long Wang , Cheng-Zhi Ye , Run Cheng , Guo-Hua Liang , Hui Liu

We show that the Einstein-Hilbert action for the gravitational field can be obtained as a linear low-energy approximation for the dynamical massless fields in the theory with the lagrangian quadratic in the gauge field strength-tensor of…

High Energy Physics - Phenomenology · Physics 2007-05-23 V. V. Kiselev

The gauge approach to gravity based on the local Lorentz group with a general independent affine connection A_{\mu cd} is developed. We consider SO(1,3) gauge theory with a Lagrangian quadratic in curvature as a simple model of quantum…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Sang-Woo Kim , D. G. Pak

The correct quantum description for a curvature squared term in the action can be obtained by casting the action in the canonical form with the introduction of a variable which is the negative of the first derivative of the field variable…

General Relativity and Quantum Cosmology · Physics 2008-11-26 A. K. Sanyal , B. Modak

A manifestly Lorentz-covariant formulation of Loop Quantum Gravity (LQG) is given in terms of finite-dimensional representations of the Lorentz group. The formulation accounts for discrete symmetries, such as parity and time-reversal, and…

General Relativity and Quantum Cosmology · Physics 2021-12-08 Francesco Cianfrani

Spin networks in Loop Quantum Gravity are traditionally described by unitary holonomies corresponding to noiseless transformations. In this work, we extend this framework to incorporate general quantum channels that model effects of…

General Relativity and Quantum Cosmology · Physics 2026-02-13 Bartosz Grygielski , Jakub Mielczarek

We apply the ADM approach to obtain a Hamiltonian description of the Einstein-Hilbert action. In doing so we add four new ingredients: (i) We eliminate the diffeomorphism constraints. (ii) We replace the densities $\sqrt g$ by a function…

General Relativity and Quantum Cosmology · Physics 2014-05-01 Claus Gerhardt

Motivated by the prospect of constraining microscopic models, we calculate the exact one-loop corrected de Sitter entropy (the logarithm of the sphere partition function) for every effective field theory of quantum gravity, with particles…

High Energy Physics - Theory · Physics 2022-02-22 Dionysios Anninos , Frederik Denef , Y. T. Albert Law , Zimo Sun

The recent analysis of quantum cosmology by S. Gielen [1] is extended by discussing the case of dust (in the flat case). The dependence of the Wheeler-DeWitt equation on the operator ordering of the Hamiltonian in the case of a position…

General Relativity and Quantum Cosmology · Physics 2024-07-17 Rudolf Baier , Christian Peterson

We study the quantum fermions+gravity system, that is, the gravitational counterpart of QED. We start from the standard Einstein-Weyl theory, reformulated in terms of Ashtekar variables; and we construct its non- perturbative quantum theory…

General Relativity and Quantum Cosmology · Physics 2009-10-22 H A Marales-Tecotl , C Rovelli

We discuss the universal spin dynamics in quasi one-dimensional systems including the real spin in narrow-gap semiconductors like InAs and InSb, the valley pseudospin in staggered single-layer graphene, and the combination of real spin and…

Mesoscale and Nanoscale Physics · Physics 2017-10-17 E. A. Fajardo , U. Zülicke , R. Winkler
‹ Prev 1 4 5 6 7 8 10 Next ›