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Related papers: Quantum dynamics as a pseudo-density matrix

200 papers

According to quantum theory, a scientist in a sealed laboratory cannot tell whether they are inside a superposition or not. Consequently, so long as they remain isolated, they can assume without inconsistency that their measurements result…

Quantum Physics · Physics 2023-08-28 Jacques L. Pienaar

A time-dependent theory for the interactions between spatially separated lossy cavities in a homogeneous background medium using quantized quasinormal modes (QNMs) is presented. The cavities interact via a bath of traveling photons,…

Mesoscale and Nanoscale Physics · Physics 2026-04-15 Robert Meiners Fuchs , Juanjuan Ren , Sebastian Franke , Stephen Hughes , Marten Richter

A formalism is presented in which quantum particle dynamics can be developed on its own rather than `quantization' of an underlying classical theory. It is proposed that the unification of probability and dynamics should be considered as…

Quantum Physics · Physics 2007-05-23 Tulsi Dass

Quantum theory predicts probabilities as well as relative phases between different alternatives of the system. A unified description of both probabilities and phases comes through a generalisation of the notion of a density matrix for…

Quantum Physics · Physics 2016-09-08 Charis Anastopoulos

We consider the problem of quantum behavior in the finite background. Introduction of continuum or other infinities into physics leads only to technical complications without any need for them in description of empirical observations. The…

Quantum Physics · Physics 2012-02-15 Vladimir V. Kornyak

Density matrices are powerful mathematical tools for the description of closed and open quantum systems. Recently, methods for the direct computation of density matrix elements in scalar quantum field theory were developed based on thermo…

High Energy Physics - Theory · Physics 2025-03-12 Christian Käding , Mario Pitschmann

The nonequilibrium dynamics in chaotic quantum systems denies a fully understanding up to now, even if thermalization in the long-time asymptotic state has been explained by the eigenstate thermalization hypothesis which assumes a universal…

Statistical Mechanics · Physics 2020-12-08 Xinxin Yang , Pei Wang

Complex extension of quantum mechanics and the discovery of pseudo-unitarily invariant random matrix theory has set the stage for a number of applications of these concepts in physics. We briefly review the basic ideas and present…

Quantum Physics · Physics 2013-02-13 Shashi. C. L. Srivastava , S. R. Jain

Active matter denotes a system of particles immersed in an external environment, from which the particles extract energy continuously in order to perform directed motion. Extending the paradigm of active matter to a quantum framework…

We analyze the time evolution describing a quantum source for noninteracting particles, either bosons or fermions. The growth behaviour of the particle number (trace of the density matrix) is investigated, leading to spectral criteria for…

Mathematical Physics · Physics 2015-05-14 Maximilian Butz , Herbert Spohn

We derive quantum kinetic equations for fermions in a homogeneous time-dependent background in presence of decohering collisions, by use of the Schwinger-Keldysh CTP-formalism. The quantum coherence (between particles and antiparticles) is…

High Energy Physics - Phenomenology · Physics 2009-03-24 Matti Herranen , Kimmo Kainulainen , Pyry Matti Rahkila

To address Quantum Artificial Neural Networks as quantum dynamical computing systems, a formalization of quantum artificial neural networks as dynamical systems is developed, expanding the concept of unitary map to the neural computation…

Quantum Physics · Physics 2022-03-22 Carlos Pedro Gonçalves

The mean evolution of an open quantum system in continuous time is described by a time continuous semigroup of quantum channels (completely positive and trace-preserving linear maps). Baumgartner and Narnhofer presented a general…

Quantum Physics · Physics 2025-12-05 Nicolas Mousset , Nina H. Amini

We provide a new characterisation of quantum supermaps in terms of an axiom that refers only to sequential and parallel composition. Consequently, we generalize quantum supermaps to arbitrary monoidal categories and operational…

Quantum Physics · Physics 2026-03-11 Matt Wilson , Giulio Chiribella , Aleks Kissinger

What is the quantum state of the universe? Although there have been several interesting suggestions, the question remains open. In this paper, I consider a natural choice for the universal quantum state arising from the Past Hypothesis, a…

Quantum Physics · Physics 2019-01-25 Eddy Keming Chen

In my talk I will present an overview of our recent work involving the use of supersymmetric quantum mechanics (SUSY-QM). I begin by discussing the mathematical underpinnings of SUSY-QM and then discuss how we have used this for developing…

Quantum Physics · Physics 2010-05-21 Eric R. Bittner , Donald J. Kouri

Quantum devices are subject to natural decay. We propose to study these decay processes as the Markovian evolution of quantum channels, which leads us to dynamical semigroups of superchannels. A superchannel is a linear map that maps…

Quantum Physics · Physics 2022-07-22 Markus Hasenöhrl , Matthias C. Caro

We study the real-time evolution of a self-interacting O(N) scalar field initially prepared in a pure quantum state. We present a complete solution of the nonequilibrium quantum dynamics from a 1/N-expansion of the two-particle-irreducible…

High Energy Physics - Phenomenology · Physics 2010-11-11 Alexandre Giraud , Julien Serreau

Following arXiv:2210.12963 [hep-th], we investigate aspects of the time evolution operator regarded as a density operator and associated entanglement-like structures in various quantum systems. These involve timelike separations and…

High Energy Physics - Theory · Physics 2024-04-29 K. Narayan , Hitesh K. Saini

The reduced density matrix that characterises the state of an open quantum system is a projection from the full density matrix of the quantum system and its environment, and there are many full density matrices consistent with a given…

Quantum Physics · Physics 2024-11-28 Claudia L. Clarke , Ian J. Ford