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Related papers: Circuit complexity for free fermions

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Warped conformal field theories in two dimensions are exotic nonlocal, Lorentz violating field theories characterized by Virasoro-Kac-Moody symmetries and have attracted a lot of attention as candidate boundary duals to warped AdS$_3$…

High Energy Physics - Theory · Physics 2023-01-19 Arpan Bhattacharyya , Gaurav Katoch , Shubho R. Roy

The effects of a boundary on the circuit complexity are studied in two dimensional theories. The analysis is performed in the holographic realization of a conformal field theory with a boundary by employing different proposals for the dual…

High Energy Physics - Theory · Physics 2021-04-15 Paolo Braccia , Aldo L. Cotrone , Erik Tonni

We construct entanglement renormalization schemes which provably approximate the ground states of non-interacting fermion nearest-neighbor hopping Hamiltonians on the one-dimensional discrete line and the two-dimensional square lattice.…

We present a new Python package that uses the established notion of geometric quantum complexity to numerically compute the difficulty associated with preparing a given unitary transformation on a quantum computer. The numerical procedure…

A quasi-Gaussian approximation scheme is formulated to study the strongly correlated imbalanced fermions thermodynamics, where the mean-field theory is not applicable. The non-Gaussian correlation effects are understood to be captured by…

Statistical Mechanics · Physics 2009-08-26 Ji-sheng Chen , Fang Qin , Yan-ping Wang

Conventional descriptions of higher-spin fermionic gauge fields appear in two varieties: the Aragone-Deser-Vasiliev frame-like formulation and the Fang-Fronsdal metric-like formulation. We review, clarify and elaborate on some essential…

High Energy Physics - Theory · Physics 2018-02-13 Rakibur Rahman

Local Hamiltonians of fermionic systems on a lattice can be mapped onto local qubit Hamiltonians. Maintaining the locality of the operators comes at the expense of increasing the Hilbert space with auxiliary degrees of freedom. In order to…

Quantum Physics · Physics 2023-02-22 Jannes Nys , Giuseppe Carleo

In the Einstein-Cartan theory of torsion-free gravity coupling to massless fermions, the four-fermion interaction is induced and its strength is a function of the gravitational and gauge couplings, as well as the Immirzi parameter. We study…

High Energy Physics - Theory · Physics 2008-11-26 She-Sheng Xue

We review the structure of local Lagrangians and field equations for free bosonic and fermionic gauge fields of mixed symmetry in flat space. These are first presented in a constrained setting extending the metric formulation of linearized…

High Energy Physics - Theory · Physics 2021-02-24 Andrea Campoleoni

We present a relativistic analysis of fermions in an external electric field by non-perturbatively solving the Dirac equation with a static gauge. Different from the magnetic field effect, the fermion wave function in an electric field…

Nuclear Theory · Physics 2026-05-08 Xuan Zhao , Yi Wang , Pengfei Zhuang

Systems of interacting fermions can give rise to ground states whose correlations become effectively free-fermion-like in the thermodynamic limit, as shown by Baxter for a class of integrable models that include the one-dimensional XYZ…

Strongly Correlated Electrons · Physics 2022-07-21 Gabriel Matos , Andrew Hallam , Aydin Deger , Zlatko Papić , Jiannis Pachos

The quantum fluctuations of the Dirac field in external classical gravitational and electromagnetic fields are studied. A self-consistent equation for torsion is calculated, which is obtained using one-loop fermion diagrams.

High Energy Physics - Theory · Physics 2022-07-21 S. N. Vergeles

We identify natural degrees of freedom of polycrystalline materials -- affine transformations of grains -- with those of a three-dimensional lattice theory for $(T\otimes\Omega)(\mathbb{R}^3)$. We define a lattice Dirac operator on this…

High Energy Physics - Theory · Physics 2007-05-23 I. Schmelzer

In terms of the relational approach to space-time geometry and physical interactions, we show that the Dirac equation for a free fermion in the momentum representation can be obtained starting from a binary system of complex relations…

Mathematical Physics · Physics 2022-12-06 Anton V. Solov'yov

We derive the interaction of fermions with a dynamical space-time based on the postulate that the description of physics should be independent of the reference frame, which means to require the form-invariance of the fermion action under…

General Relativity and Quantum Cosmology · Physics 2021-08-31 Jürgen Struckmeier , David Vasak

Complex-valued Gaussian processes are used in Bayesian frequency-domain system identification as prior models for regression. If each realization of such a process were an $H_\infty$ function with probability one, then the same model could…

Systems and Control · Electrical Eng. & Systems 2022-11-30 Alex Devonport , Peter Seiler , Murat Arcak

Free quantum field theories on curved backgrounds are discussed via three explicit examples: the real scalar field, the Dirac field and the Proca field. The first step consists of outlining the main properties of globally hyperbolic…

Mathematical Physics · Physics 2015-05-19 Marco Benini , Claudio Dappiaggi

Defining complexity in quantum field theory is a difficult task, and the main challenge concerns going beyond free models and associated Gaussian states and operations. One take on this issue is to consider conformal field theories in 1+1…

High Energy Physics - Theory · Physics 2021-01-28 Mario Flory , Michal P. Heller

We study the quantum mechanics of a Dirac fermion on a curved spacetime manifold. The metric of the spacetime is completely arbitrary, allowing for the discussion of all possible inertial and gravitational field configurations. In this…

General Relativity and Quantum Cosmology · Physics 2013-12-04 Yuri N. Obukhov , Alexander J. Silenko , Oleg V. Teryaev

We study correlations in a bipartite, Fermionic, free state in terms of perturbations induced by one party on the other. In particular, we show that all so conditioned free states can be modelled by an auxiliary Fermionic system and a…

Quantum Physics · Physics 2009-12-04 M. Fannes , J. Wouters