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Related papers: Weak Coherent States and their Path Integrals

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We examine the circuit complexity of coherent states in a free scalar field theory, applying Nielsen's geometric approach as in [1]. The complexity of the coherent states have the same UV divergences as the vacuum state complexity and so we…

High Energy Physics - Theory · Physics 2018-10-10 Minyong Guo , Juan Hernandez , Robert C. Myers , Shan-Ming Ruan

Discrete coherent states for a system of $n$ qubits are introduced in terms of eigenstates of the finite Fourier transform. The properties of these states are pictured in phase space by resorting to the discrete Wigner function

Quantum Physics · Physics 2009-10-16 C. Munoz , A. B. Klimov , L. L. Sanchez-Soto , G. Bjork

In the paper our aim was to study the properties of a new version of coherent states whose argument is a linear combination of two special singular square 2 x 2 matrix, having a single nonzero element, equal to 1, and two labeling complex…

Quantum Physics · Physics 2026-02-02 Dušan Popov

Decoherence inevitably happens when a quantum state is exposed to its environment, which can affect quantum critical points (QCP) in a nontrivial way. As was pointed out in recent literature on $(1+1)d$ conformal field theory (CFT), the…

Statistical Mechanics · Physics 2023-08-22 Jong Yeon Lee , Chao-Ming Jian , Cenke Xu

We show that the emergence of time evolution in an otherwise timeless nonrelativistic closed quantum system -- viewed as a poor man's model of generally covariant quantum theory -- can be understood from the perspective of the path integral…

General Relativity and Quantum Cosmology · Physics 2026-05-19 Juan Manuel Diaz , Alejandro Perez

The Cahn-Hilliard equation is the most common model to describe phase separation processes of a mixture of two components. For a better description of short-range interactions of the material with the solid wall, various dynamic boundary…

Analysis of PDEs · Mathematics 2020-10-20 Harald Garcke , Patrik Knopf

Although the path-integral formalism is known to be equivalent to conventional quantum mechanics, it is not generally obvious how to implement path-based calculations for multi-qubit entangled states. Whether one takes the formal view of…

Quantum Physics · Physics 2022-06-08 Narayani Tyagi , Ken Wharton

We describe in detail a physical situation in which instantons are necessarily complex, not just Wick rotations of classical solutions to Euclidean spacetime. These complex instantons arise in the semiclassical evaluation of vacuum pair…

High Energy Physics - Theory · Physics 2012-05-15 Cesim K. Dumlu , Gerald V. Dunne

The quantum coherence of a multipartite system is investigated when some of the parties are moving with uniform acceleration and the analysis is carried out using the single mode approximation. Due to acceleration the quantum coherence is…

Unitarity is a difficult concept to implement in canonical quantum gravity because of state non-normalizability and the problem of time. We take a realist approach based on pilot-wave theory to address this issue in the Ashtekar formulation…

General Relativity and Quantum Cosmology · Physics 2024-05-07 Indrajit Sen , Stephon Alexander , Justin Dressel

We present a computation of the coherent state path integral for a generic linear system using ``functional methods'' (as opposed to discrete time approaches). The Gaussian phase space path integral is formally given by a determinant built…

Quantum Physics · Physics 2009-11-11 C. G. Torre

\(\Un{N}\) coherent states over Grassmann manifold, \(\grsmn{N}{n}\simeq\Un{N}/ (\Un{n}\times \Un{N-n})\), are formulated to be able to argue the WKB-exactness, so called the localization of Duistermaat-Heckman, in the path integral…

High Energy Physics - Theory · Physics 2009-10-28 Kazuyuki Fujii , Taro Kashiwa , Seiji Sakoda

We introduce a quantifier of phase-space complexity for discrete-variable (DV) quantum systems. Motivated by a recent framework developed for continuous-variable systems, we construct a complexity measure of quantum states based on the…

Quantum Physics · Physics 2026-03-05 Siting Tang , Shunlong Luo , Matteo G. A. Paris

In this article, we study quantum coherence of bipartite state from the perspective of weak measurement, which generalizes the notion of coherence relative to measurement. The is being illustrated by computing coherence for the well-known…

Quantum Physics · Physics 2023-04-06 Indrajith V. S , R. Muthuganesan , R. Sankaranarayanan

We study the application of the coherent-state path integral as a numerical tool for wave-packet propagation. The numerical evaluation of path integrals is reduced to a matrix-vector multiplication scheme. Together with a split-operator…

Quantum Physics · Physics 2007-05-23 Bernd Burghardt , Joachim Stolze

A sketch of a recent approach to quantum gravity is presented which involves several unconventional aspects. The basic ingredients include: (1) Affine kinematical variables; (2) Affine coherent states; (3) Projection operator approach for…

General Relativity and Quantum Cosmology · Physics 2017-08-23 John R. Klauder

The path integral approach to the quantization of one degree-of-freedom Newtonian particles is considered within the discrete time-slicing approach, as in Feynman's original development. In the time-slicing approximation the quantum…

Exactly Solvable and Integrable Systems · Physics 2009-11-11 Chris M. Field , Frank W. Nijhoff

The aim of this article is to study a Cahn-Hilliard model for a multicomponent mixture with cross-diffusion effects, degenerate mobility and where only one of the species does separate from the others. We define a notion of weak solution…

Analysis of PDEs · Mathematics 2020-07-03 Virginie Ehrlacher , Greta Marino , Jan-Frederik Pietschmann

A quantum transition can be seen as a result of interference between various pathways(e.g. Feynman paths) which can be labelled by a variable $f$. An attempt to determine the value of f without destroying the coherence between the pathways…

Quantum Physics · Physics 2009-05-26 D. Sokolovski

We present a new method for the consistent construction of time-continuous coherent-state path integrals using the theory of half-form quantization. Through the inversion of the quantization procedure we construct a de-quantization map…

Quantum Physics · Physics 2020-06-25 P. Lykourgias , I. Lyris , A. I. Karanikas