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Related papers: Quantum Filtering at Finite Temperature

200 papers

We investigate an asymptotically spatially flat Robertson-Walker spacetime from two different perspectives. First, using von Neumann entropy, we evaluate the entanglement generation due to the encoded information in spacetime. Then, we work…

Quantum Physics · Physics 2017-06-21 Mehrnoosh Farahmand , Hosein Mohammadzadeh , Hossein Mehri-Dehnavi

For a given diagrammatic approximation in many-body perturbation theory it is not guaranteed that positive observables, such as the density or the spectral function, retain their positivity. For zero-temperature systems we developed a…

Mathematical Physics · Physics 2022-08-23 Markku J. Hyrkäs , Daniel Karlsson , Robert van Leeuwen

We discuss in general how to geometrically visualize a qudit system, with a particular interest in thermal states. The principle of maximum entropy is used to study the geometric properties of an ensemble of finite dimensional Hamiltonian…

Quantum Physics · Physics 2025-02-10 J. A. López-Saldívar , O. Castaños , S. Cordero , E. Nahmad-Achar , R. López-Peña

We give a tutorial exposition of the analogue of the filtering equation for quantum systems focusing on the quantum probabilistic framework and developing the ideas from the classical theory. Quantum covariances and conditional expectations…

Mathematical Physics · Physics 2022-05-25 John E. Gough

Quantum thermalization describes how closed quantum systems can effectively reach thermal equilibrium, resolving the apparent incongruity between the reversibility of Schr\"odinger's equation and the second law of thermodynamics. Despite…

Quantum Physics · Physics 2026-01-08 Saúl Pilatowsky-Cameo , Soonwon Choi

This work continues the investigation in two recent papers on the quantum thermodynamics of spacetimes, 1) placing what was studied in [1] for thermal quantum fields in the context of early universe cosmology, and 2) extending the…

High Energy Physics - Theory · Physics 2024-11-26 Jen-Tsung Hsiang , Yu-Cun Xie , Bei-Lok Hu

The method of the real time perturbative calculations of nonequilibrium averages is generalised to the case of varying chemical potential. Calculations are performed in the frame of Zubarev's nonequilibrium density matrix approach. In this…

High Energy Physics - Phenomenology · Physics 2016-09-01 Tengiz M. Bibilashvili

It is shown how quantum field theory at finite temperature can be used to set up self-consistent and gauge invariant equations for cosmological perturbations sustained by an ultrarelativistic plasma. While in the collisionless case, the…

General Relativity and Quantum Cosmology · Physics 2016-08-31 Anton K. Rebhan

Feedback cooling plays a critical role in stabilizing quantum systems and achieving low temperatures, where a key question is to determine the fundamental thermodynamic limits on cooling performance. We establish a fundamental bound on…

Quantum Physics · Physics 2025-09-08 Kousuke Kumasaki , Toshihiro Yada , Ken Funo , Takahiro Sagawa

Physical spacetime geometry follows from some effective thermodynamics of quantum states of all fields and particles described in frames of General Relativity. In the sense of pure field theoretical Einstein's point of view on gravitation…

General Relativity and Quantum Cosmology · Physics 2008-08-27 L. A. Glinka

The interplay of quantum and thermal fluctuations in the vicinity of a quantum critical point characterizes the physics of strongly correlated systems. Here we investigate this interplay from a quantum information perspective presenting the…

Strongly Correlated Electrons · Physics 2018-10-30 Marco Gabbrielli , Augusto Smerzi , Luca Pezzè

Yang-Mills theory is studied at finite temperature within the Hamiltonian approach in Coulomb gauge by means of the variational principle using a Gaussian type ansatz for the vacuum wave functional. Temperature is introduced by…

High Energy Physics - Theory · Physics 2015-04-22 J. Heffner , H. Reinhardt

I construct lowest-energy representations of non-centrally extended algebras of Noether symmetries, including diffeomorphisms and reparametrizations of the observer's trajectory. This may be viewed as a new scheme for quantization. First…

Mathematical Physics · Physics 2007-05-23 T. A. Larsson

In the present work, we study the noncommutative version of a quantum cosmology model. The model has a Friedmann-Robertson-Walker geometry, the matter content is a radiative perfect fluid and the spatial sections have positive constant…

General Relativity and Quantum Cosmology · Physics 2016-05-05 G. Oliveira-Neto , G. A. Monerat , E. V. Corrêa Silva , C. Neves , L. G. Ferreira Filho

We introduce a model for charge and heat transport based on the Landauer-Buttiker scattering approach. The system consists of a chain of $N$ quantum dots, each of them being coupled to a particle reservoir. Additionally, the left and right…

Mesoscale and Nanoscale Physics · Physics 2009-03-19 Philippe A. Jacquet

For every local quantum field theory on a static, globally hyperbolic spacetime of arbitrary dimension, assuming the Reeh-Schlieder property, local preparability of states, and the existence of an energy density as operator-valued…

Mathematical Physics · Physics 2022-10-14 Albert Much , Albert Georg Passegger , Rainer Verch

This paper investigates the finite-temperature behavior of Conformal Field Theory (CFT) in Rindler vacuum, focusing on the relation between acceleration and thermality in quantum field theory. We illustrate how uniformly accelerated…

General Relativity and Quantum Cosmology · Physics 2024-10-02 Iftekher S. Chowdhury , Binay Prakash Akhouri , Shah Haque , Eric Howard

We construct upper bounds on entanglement entropies of many-body quantum states that have fixed energy expectation values with respect to geometrically local Hamiltonians. Our focus is on entanglement entropies of subsystems that make up…

Statistical Mechanics · Physics 2026-04-16 Samuel J. Garratt , Dmitry A. Abanin

The dynamics of many open quantum systems are described by stochastic master equations. In the discrete-time case, we recall the structure of the derived quantum filter governing the evolution of the density operator conditioned to the…

Optimization and Control · Mathematics 2015-03-23 Pierre Six , Philippe Campagne-Ibarcq , Landry Bretheau , Benjamin Huard , Pierre Rouchon

Understanding the thermodynamic properties of many-body quantum systems and their emergence from microscopic laws is a topic of great significance due to its profound fundamental implications and extensive practical applications. Recent…

Quantum Physics · Physics 2024-09-05 Antonio Palamara , Francesco Plastina , Antonello Sindona , Irene D'Amico