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Related papers: Coherent State Functional Integrals in Quantum Cos…

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A new formalism is introduced to treat problems in quantum field theory, using coherent functional expansions rather than path integrals. The basic results and identities of this approach are developed. In the case of a Bose gas with…

Quantum Physics · Physics 2017-10-25 P. D. Drummond

We introduce a set of coherent states which are associated with quantum systems governed by a trilinear boson Hamiltonian. These states are produced by the action of a nonunitary displacement operator on a reference state and can be…

Quantum Physics · Physics 2009-10-30 C. Brif

In this paper, the Higgs-like approach is used to analyze the quantum dynamics of a harmonic oscillator constrained on a circle. We obtain the Hamiltonian of this system as a function of the Cartesian coordinate of the tangent line through…

Quantum Physics · Physics 2022-07-27 Ali Mahdifar , Ehsan Amooghorban

Quantum states transformation under free operations plays a central role in the resource theory of coherence. In this paper, we investigate the transformation from a mixed coherent state into a pure one by using both incoherent operations…

Quantum Physics · Physics 2021-01-01 C. L. Liu , D. L. Zhou

The quantum description of time evolution in non-linear gravitational systems such as cosmological space-times is not well understood. We show, in the simplified setting of mini-superspace, that time evolution of this system can be obtained…

General Relativity and Quantum Cosmology · Physics 2023-05-02 Anne-Katherine Burns , David E. Kaplan , Tom Melia , Surjeet Rajendran

The path-integral approach to cosmology consists in the computation of transition amplitudes between states of the quantum geometry of the universe. In the past, the concrete computation of these transitions amplitudes has been performed in…

General Relativity and Quantum Cosmology · Physics 2012-05-22 Francesca Vidotto

The set of coherent states for a noncommutative quantum Bianchi I anisotropic cosmology were built to circumvent the absence of a simultaneous set of configuration observables. By extending known methods of path integrals with coherent…

General Relativity and Quantum Cosmology · Physics 2014-03-13 Román Juárez , David Martínez

The paper presents an interesting mathematical feedback between the formalism of coherent states and the field of integrals and integral representations involving special functions. This materializes through an easy and fast method to…

Quantum Physics · Physics 2024-08-21 Dušan Popov

This paper examines the nature of classical correspondence in the case of coherent states at the level of quantum trajectories. We first show that for a harmonic oscillator, the coherent state complex quantum trajectories and the complex…

Quantum Physics · Physics 2015-05-27 Moncy V. John , Kiran Mathew

A quantum spin system can be modelled by an equivalent classical system, with an effective Hamiltonian obtained by integrating all non-zero frequency modes out of the path integral. The effective Hamiltonian H_eff(S_i) derived from the…

Quantum Physics · Physics 2007-05-23 J H Samson

Unique set of coherent states for the anharmonic oscillator is obtained by requiring i. under the quantum mechanical time evolution a coherent state evolves into another, governed by trajectory in the classical phase space (of a related…

Quantum Physics · Physics 2007-05-23 H. S. Sharatchandra

We present a new method for constructing operators in loop quantum gravity. The construction is an application of the general idea of "coherent state quantization", which allows one to associate a unique quantum operator to every function…

General Relativity and Quantum Cosmology · Physics 2015-11-18 Emanuele Alesci , Andrea Dapor , Jerzy Lewandowski , Ilkka Makinen , Jan Sikorski

Quantum coherence, the ability of a quantum system to be in a superposition of orthogonal quantum states, is a distinct feature of the quantum mechanics, thus marking a deviation from classical physics. Coherence finds its applications in…

Quantum Physics · Physics 2023-01-18 Najmeh Etehadi Abari , Andrey Rakhubovsky , Radim Filip

Coherent states possess a regularized path integral and gives a natural relation between classical variables and quantum operators. Recent work by Klauder and Whiting has included extended variables, that can be thought of as gauge fields,…

Quantum Physics · Physics 2008-02-03 M. C. Ashworth

The Feynman path integral for the generalized harmonic oscillator is reviewed, and it is shown that the path integral can be used to find a complete set of wave functions for the oscillator. Harmonic oscillators with different…

Quantum Physics · Physics 2007-05-23 Dae-Yup Song

We develop a general framework for effective equations of expectation values in quantum cosmology and pose for them the quantum Cauchy problem with no-boundary and tunneling wavefunctions. Cosmological configuration space is decomposed into…

General Relativity and Quantum Cosmology · Physics 2009-10-31 A. O. Barvinsky , D. V. Nesterov

Quantum mechanical phase space path integrals are re-examined with regard to the physical interpretation of the phase space variables involved. It is demonstrated that the traditional phase space path integral implies a meaning for the…

Quantum Physics · Physics 2007-05-23 John R. Klauder

Coherent states on the quantum group $SU_q(2)$ are defined by using harmonic analysis and representation theory of the algebra of functions on the quantum group. Semiclassical limit $q\rightarrow 1$ is discussed and the crucial role of…

High Energy Physics - Theory · Physics 2010-11-01 I. Ya. Aref'eva , R. Parthasarathy , K. S. Viswanathan , I. V. Volovich

We address the nonadiabatic quantum dynamics of macrosystems with several coupled electronic states, taking into account the possibility of multi-state conical intersections. The general situation of an arbitrary number of states and…

Chemical Physics · Physics 2009-11-13 Etienne Gindensperger , Lorenz S. Cederbaum

In this paper, we formulate the phase space description of qubit systems using coadjoint orbits of $SU(2)$ and the Stratonovich-Weyl correspondence, yielding a deformation quantization on the sphere. The resulting star product reproduces…

Quantum Physics · Physics 2026-04-08 Jasel Berra-Montiel , Alberto Molgado , Mar Sánchez-Córdova