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Related papers: Grassmann Phase Space Methods for Fermions. II. Fi…

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We present a new variational method for investigating the ground state and out of equilibrium dynamics of quantum many-body bosonic and fermionic systems. Our approach is based on constructing variational wavefunctions which extend Gaussian…

Quantum Physics · Physics 2018-03-14 Tao Shi , Eugene Demler , J. Ignacio Cirac

We provide a brief review of how phase space techniques are explored within strong-field and attosecond science. This includes a broad overview of the existing landscape, with focus on strong-field ionisation and rescattering, high-order…

Atomic Physics · Physics 2021-07-28 H. Chomet , C. Figueira de Morisson Faria

It is shown that an arbitrary Fermion hopping hamiltonian can be represented by a system with no fermion fields, generalising earlier results by M. Levin & X.G. Wen [Phys Rev B 67, 245316 (2003)]. All the operators in the hamiltonian of…

Strongly Correlated Electrons · Physics 2009-11-10 R. C. Ball

Charret et. al. applied the properties of the Grassmann generators to develop a new method to calculate the coefficients of the high temperature expansion of the grand canonical partition function of self-interacting fermionic models in any…

High Energy Physics - Theory · Physics 2016-09-06 S. M. de Souza , O. Rojas Santos , M. T. Thomaz

Using many-body techniques we obtain the time-dependent Gaussian approximation for interacting fermion-scalar field models. This method is applied to an uniform system of relativistic spin-1/2 fermion field coupled, through a Yukawa term,…

High Energy Physics - Theory · Physics 2009-10-31 E. R. Takano Natti , Chi-Yong Lin , A. F. R de Toledo Piza , P. L. Natti

We find a mapping between the attractive Fermi-Hubbard model and the repulsive Bose-Hubbard model at finite temperature and at imaginary chemical potential $\mu =i\theta$. We show, by using a large $N$-expansion, that the partition…

Quantum Gases · Physics 2026-05-12 Evangelos G. Filothodoros

The article represents a research of the cosmological evolution of fermion statistical systems with fantom scalar interaction where "kinetic" term's contribution to the total energy of a scalar field is negative. As a result of analytical…

General Relativity and Quantum Cosmology · Physics 2016-08-18 Yurii Ignat'ev , Alexander Agathonov , Dmitry Ignatyev

The Gaussian phase-space representation can be used to implement quantum dynamics for fermionic particles numerically. To improve numerical results, we explore the use of dynamical diffusion gauges in such implementations. This is achieved…

Mathematical Physics · Physics 2023-12-07 F Rousse , M Fasi , A Dmytryshyn , M Gulliksson , M Ogren

We investigate the stability of the Sarma phase in two-component fermion systems in three spatial dimensions. For this purpose we compare strongly-correlated systems with either relativistic or non-relativistic dispersion relation:…

Quantum Gases · Physics 2015-01-26 I. Boettcher , T. K. Herbst , J. M. Pawlowski , N. Strodthoff , L. von Smekal , C. Wetterich

The fuzzy-sphere regularisation is a powerful tool to study conformal field theories (CFT) in three spacetime dimensions. In this paper, we extend its scope to CFTs with local fermionic operators. We realise the free-Majorana-fermion CFT on…

High Energy Physics - Theory · Physics 2026-02-27 Zheng Zhou , Davide Gaiotto , Yin-Chen He

In recent literature on trapped ultracold atomic gases, calculations for 2D-systems are often done within the Dynamical Mean Field Theory (DMFT) approximation. In this paper, we compare DMFT to a fully two-dimensional, self-consistent…

Quantum Gases · Physics 2011-10-21 Andreas D. Pfister , Eberhard Jakobi , Tobias Gottwald , Peter G. J. van Dongen

This note is devoted to representation of some evolution semigroups. The semigroups are generated by pseudo-differential operators, which are obtained by different (parametrized by a number $\tau$) procedures of quantization from a certain…

Functional Analysis · Mathematics 2017-07-03 Yana Butko , Martin Grothaus , Oleg Smolyanov

Knowledge on evolving physical fields is of paramount importance in science, technology, and economics. Dynamical field inference (DFI) addresses the problem of reconstructing a stochastically driven, dynamically evolving field from finite…

Quantum Physics · Physics 2021-12-22 Margret Westerkamp , Igor Ovchinnikov , Philipp Frank , Torsten Enßlin

We study the real-time dynamics of fermions coupled to scalar fields in a linear sigma model, which is often employed in the context of preheating after inflation or as a low-energy effective model for quantum chromodynamics. We find a…

High Energy Physics - Phenomenology · Physics 2014-01-15 J. Berges , D. Gelfand , D. Sexty

A complete set of formulae in terms of the moment-operator expansion is presented for the two-meson, two-photon and fermion-antifermion states that can be used in the analysis of scalar (S) and pseudoscalar (P) meson production in anti-p p…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. V. Anisovich , V. V. Anisovich , V. N. Markov , M. A. Matveev , A. V. Sarantsev

A recent time-of-flight (TOF) expansion experiment with polarized fermionic erbium atoms measured a Fermi surface deformation from a sphere to an ellipsoid due to dipole-dipole interaction, thus confirming previous theoretical predictions.…

Quantum Gases · Physics 2017-05-30 Vladimir Veljic , Antun Balaz , Axel Pelster

We establish equations for scalar and fermion fields using results obtained from a study on a phase space representation of quantum theory that we have performed in a previous work. Our approaches are similar to the historical ones to…

We review problems involving the use of Grassmann techniques in the field of classical spin systems in two dimensions. These techniques are useful to perform exact correspondences between classical spin Hamiltonians and field-theory…

Statistical Mechanics · Physics 2016-11-25 Maxime Clusel , Jean-Yves Fortin

Contents 1. Creation and annihilation operators for the system of indistinguishable particles 1.1 The permutation group and the states of a system of indistinguishable particles 1.2 Dimension of the Hilbert space of a system of…

Quantum Gases · Physics 2013-08-16 V. S. Shchesnovich

We provide a Hilbert space approach to quantum mechanics where space and time are treated on an equal footing. Our approach replaces the standard dependence on an external classical time parameter with a spacetime-symmetric algebraic…

Quantum Physics · Physics 2026-02-10 N. L. Diaz , R. Rossignoli