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Related papers: Quantum mechanics in phase space: First order comp…

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The Wigner function provides a useful quasiprobability representation of quantum mechanics, with applications in various branches of physics. Many nice properties of the Wigner function are intimately connected with the high symmetry of the…

Quantum Physics · Physics 2016-02-03 Huangjun Zhu

A quantum mechanical wave of a finite size moves like a classical particle and shows a unique decay probability. Because the wave function evolves according to the Schr\"{o}dinger equation, it preserves the total energy but not the kinetic…

High Energy Physics - Phenomenology · Physics 2014-12-09 Kenzo Ishikawa , Yutaka Tobita

The emergence of classical behavior from quantum mechanics as Planck's constant $\hbar$ approaches zero remains a fundamental challenge in physics [1-3]. This paper introduces a novel approach employing deep neural networks to directly…

Quantum Physics · Physics 2025-04-24 Kamran Majid

The spread of the wave-function, or quantum uncertainty, is a key notion in quantum mechanics. At leading order, it is characterized by the quadratic moments of the position and momentum operators. These evolve and fluctuate independently…

Quantum Physics · Physics 2023-10-03 Etera R. Livine

We show that (in contrast to a rather common opinion) QM is not a complete theory. This is a statistical approximation of classical statistical mechanics on the {\it infinite dimensional phase space.} Such an approximation is based on the…

High Energy Physics - Theory · Physics 2009-11-11 Andrei Khrennikov

The Wigner function is a quantum analogue of the classical joined distribution of position and momentum. As such is should be a good tool to study quantum-classical correspondence. In this paper, the classical limit of the Wigner function…

Quantum Physics · Physics 2021-04-15 Jan Mostowski , Joanna Pietraszewicz

Representations of the Poincar\'{e} symmetry are studied by using a Hilbert space with a phase space content. The states are described by wave functions ( quasi amplitudes of probability) associated with Wigner functions (quasi probability…

High Energy Physics - Theory · Physics 2015-09-02 R. G. G. Amorim , F. C. Khanna , A. P. C. Malbouisson , J. M. C. Malbouisson , A. E. Santana

We apply the generalized Wigner function formalism to detect and characterize a range of quantum phase transitions in several cyclic, finite-length, spin-$\frac{1}{2}$ one-dimensional spin-chain models, viz., the Ising and anisotropic $XY$…

Quantum Physics · Physics 2023-10-03 N. M. Millen , R. P. Rundle , J. H. Samson , Todd Tilma , R. F. Bishop , M. J. Everitt

In this work we have explored few tools in Quantum State Tomography for Continuous Variable Systems. The concept of quantum states in phase space representation is introduced in a simple manner by using a few statistical concepts. Unlike…

Quantum Physics · Physics 2019-12-12 Ludmila Botelho

Fermionic phase space representations are a promising method for studying correlated fermion systems. The fermionic Q-function and P-function have been defined using Gaussian operators of fermion annihilation and creation operators. The…

Quantum Physics · Physics 2018-05-31 Ria Rushin Joseph , Laura E. C. Rosales-Zárate , Peter D. Drummond

The dispersions, weights, and widths of the peaks of the single-particle spectral function in the presence of pair correlations, for a Fermi gas with either attractive or repulsive short-range inter-particle interaction, are determined in…

Quantum Gases · Physics 2012-01-27 F. Palestini , A. Perali , P. Pieri , G. C. Strinati

We introduce a positive phase-space representation for fermions, using the most general possible multi-mode Gaussian operator basis. The representation generalizes previous bosonic quantum phase-space methods to Fermi systems. We derive…

Other Condensed Matter · Physics 2009-11-10 J. F. Corney , P. D. Drummond

The Fermi surface in underdoped cuprates is reconstructed by the charge density wave (CDW) order in the pseudogap phase. Theoretical proposals can be divided into two classes: one assumes the underlying Fermi surface without CDW as a…

Strongly Correlated Electrons · Physics 2016-06-24 Long Zhang , Jia-Wei Mei

We prove that Wigner functions contain a symplectic connection. The latter covariantises the symplectic exterior derivative on phase space. We analyse the role played by this connection and introduce the notion of local symplectic…

Mathematical Physics · Physics 2008-11-26 J. M. Isidro

A study on a method for the establishment of a phase space representation of quantum theory is presented. The approach utilizes the properties of Gaussian distribution, the properties of Hermite polynomials, Fourier analysis and the current…

A Fermi liquid with a 'large' Fermi surface (FL) can have a quantum phase transition to a spin density wave state (SDW) with reconstructed 'small' Fermi pockets. Both FL and SDW phases obey the Luttinger constraints on the volume enclosed…

Strongly Correlated Electrons · Physics 2025-05-13 Subir Sachdev

We re-use some original ideas of de~Broglie, Schr\"odiger, Dirac and Feynman to revise the ensemble interpretation of wave function in quantum mechanics. To this end we introduce coherence (auto-concordance) of ensembles of quantum…

Quantum Physics · Physics 2025-04-25 Vladimir V. Kisil

The quantum field of a single particle is expressed as the sum of the particle's ordinary wave function and the vacuum fluctuations. An exact quantum-field calculation shows that the squared amplitude of this field sums, at any time, to a…

Quantum Physics · Physics 2007-05-23 Benjamin Ross

We define the Wigner entropy of a quantum state as the differential Shannon entropy of the Wigner function of the state. This quantity is properly defined only for states that possess a positive Wigner function, which we name…

Quantum Physics · Physics 2022-01-03 Zacharie Van Herstraeten , Nicolas J. Cerf

Phase-space representations as given by Wigner functions are a powerful tool for representing the quantum state and characterizing its time evolution in the case of infinite-dimensional quantum systems and have been widely used in quantum…

Quantum Physics · Physics 2020-02-24 Bálint Koczor , Robert Zeier , Steffen J. Glaser