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Related papers: Fermionic Quasi-free States and Maps in Informatio…

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How much information a fermionic state contains? To address this fundamental question, we define the complexity of a particle-conserving many-fermion state as the entropy of its Fock space probability distribution, minimized over all Fock…

Quantum Physics · Physics 2024-03-06 Tuomas I. Vanhala , Teemu Ojanen

This paper is devoted to parameter estimation for partially observed polynomial state space models. This class includes discretely observed affine or more generally polynomial Markov processes. The polynomial structure allows for the…

Statistics Theory · Mathematics 2025-07-11 Jan Kallsen , Ivo Richert

The fermionic von Neumann entropy, the fermionic entanglement entropy and the fermionic relative entropy are defined for causal fermion systems. Our definition makes use of entropy formulas for quasi-free fermionic states in terms of the…

Mathematical Physics · Physics 2025-04-16 Felix Finster , Robert H. Jonsson , Magdalena Lottner , Albert Much , Simone Murro

Instead of formulating the states of a Quantum Field Theory (QFT) as density matrices over a single large Hilbert space, it has been proposed by Kijowski [Kijowski, 1977] to construct them as consistent families of partial density matrices,…

High Energy Physics - Theory · Physics 2016-04-20 Suzanne Lanéry

For the general class of quasifree fermionic right mover/left mover systems over the infinitely extended two-sided discrete line introduced in [8] within the algebraic framework of quantum statistical mechanics, we study the von Neumann…

Mathematical Physics · Physics 2025-05-27 Walter H. Aschbacher

We propose a definition of infinite dimensional Choi-Jamiolkowski state associated with a completely positive trace preserving map. We introduce the notion of Theta-KMS adjoint of a quantum Markov semigroup, which is identified with the…

Mathematical Physics · Physics 2013-09-30 Jorge R. Bolanos-Servin , Roberto Quezada

In this paper we study the time evolution of (Renyi) entanglement entropies for locally excited states in four dimensional free massless fermionic field theory. Locally excited states are defined by being acted by various local operators on…

High Energy Physics - Theory · Physics 2016-03-23 Masahiro Nozaki , Tokiro Numasawa , Shunji Matsuura

The entanglement entropy of a distinguished region of a quantum many-body system reflects the entanglement present in its pure ground state. In this work, we establish scaling laws for this entanglement for critical quasi-free fermionic and…

Quantum Physics · Physics 2014-11-11 M. Cramer , J. Eisert , M. B. Plenio

The approach is developed for the description of isolated Fermi-systems with finite number of particles, such as complex atoms, nuclei, atomic clusters etc. It is based on statistical properties of chaotic excited states which are formed by…

Statistical Mechanics · Physics 2009-08-18 V. V. Flambaum , F. M. Izrailev

We present a detailed account of quantum state estimation by joint maximization of the likelihood and the entropy. After establishing the algorithms for both perfect and imperfect measurements, we apply the procedure to data from simulated…

We present a statistical mechanics description to study the ground state of quantum systems. In this approach, averages for the complete system are calculated over the non-interacting energy levels. Taking different interaction parameter,…

Statistical Mechanics · Physics 2015-05-20 Andre M. C. Souza

The method of constructing the tomographic probability distributions describing quantum states in parallel with density operators is presented. Known examples of Husimi-Kano quasi-distribution and photon number tomography are reconsidered…

Quantum Physics · Physics 2009-02-23 V. I. Man'ko , G. Marmo , A. Simoni , E. C. G. Sudarshan , F. Ventriglia

This is a set of notes on some unrelated topics in mathematical physics, at varying levels of detail. First, I consider certain questions relating to the decay of correlation functions in matrix product states, in particular those generated…

Quantum Physics · Physics 2014-04-17 M. B. Hastings

In this paper we study the dynamics of fermionic mixed states in the mean-field regime. We consider initial states which are close to quasi-free states and prove that, under suitable assumptions on the inital data and on the many-body…

Mathematical Physics · Physics 2015-02-12 Niels Benedikter , Vojkan Jaksic , Marcello Porta , Chiara Saffirio , Benjamin Schlein

For control systems in discrete time, this paper discusses measure-theoretic invariance entropy for a subset Q of the state space with respect to a quasi-stationary measure obtained by endowing the control range with a probability measure.…

Dynamical Systems · Mathematics 2018-04-05 Fritz Colonius

Dynamic properties of fermionic systems, like contollability, reachability, and simulability, are investigated in a general Lie-theoretical frame for quantum systems theory. Observing the parity superselection rule, we treat the fully…

Quantum Physics · Physics 2014-09-18 Zoltán Zimborás , Robert Zeier , Michael Keyl , T. Schulte-Herbrueggen

We have developed a formalism that includes both quasibound states with real energies and quantum resonances within the same theoretical framework, and that admits a clean and unambiguous distinction between these states and the states of…

Quantum Physics · Physics 2014-03-11 Curt A. Moyer

The partial trace operation is usually considered in composite quantum systems, to reduce the state on a single subsystem. This operation has a key role in the decoherence effect and quantum measurements. However, partial trace operations…

Quantum Physics · Physics 2024-03-18 Quentin Ansel

A reasonable quantum information theory for fermions must respect the parity super-selection rule to comply with the special theory of relativity and the no-signaling principle. This rule restricts the possibility of any quantum state to…

We derive a rigorous, quantum mechanical map of fermionic creation and annihilation operators to continuous Cartesian variables that exactly reproduces the matrix structure of the many-fermion problem. We show how our scheme can be used to…

Chemical Physics · Physics 2018-03-20 Andrés Montoya-Castillo , Thomas E. Markland