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Related papers: Polarized Dirac fermions in de Sitter spacetime

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We consider the Dirac equations in static spherically-symmetric space-times, and we present a type of spinor field whose structure allows the separation of elevation angle and radial coordinate in very general situations. We demonstrate…

General Relativity and Quantum Cosmology · Physics 2024-05-14 Roberto Cianci , Stefano Vignolo , Luca Fabbri

Using unitary irreducible representations of the de Sitter group, we construct the Fock space of a massive free scalar field. In this approach, the vacuum is the unique dS invariant state. The quantum field is a posteriori defined by an…

High Energy Physics - Theory · Physics 2016-09-06 E. Joung , J. Mourad , R. Parentani

It is shown that in the case of the spherically symmetric static backgrounds there is a gauge in which the Dirac equation is manifestly covariant under rotations. This allows us to separate the spherical variables like in the flat…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Ion I. Cotaescu

Free noncommutative fields constitute a natural and interesting example of constrained theories with higher derivatives. The quantization methods involving constraints in the higher derivative formalism can be nicely applied to these…

High Energy Physics - Theory · Physics 2008-11-26 R. Amorim , J. Barcelos-Neto

Two dimensional conformal feld theories have been extensively studied in the past. When considered on the torus, they are strongly constrained by modular invariance. However, introducing relevant deformations or chemical potentials pushes…

High Energy Physics - Theory · Physics 2023-09-26 Jeremías Aguilera-Damia , Mario Solís , Gonzalo Torroba

The spin connections of the Dirac field have three ingredients that are connected with the Ricci rotations, the Maxwell field, and an axial field which is coupled to the axial current. I demonstrate that the axial field provides an…

High Energy Physics - Phenomenology · Physics 2007-05-23 Alexander Makhlin

In the standard model of particle physics, all fermions are fundamentally massless and only acquire their effective bare mass when the Higgs field condenses. Therefore, in a fundamental de Broglie-Bohm pilot-wave quantum field theory (valid…

Quantum Physics · Physics 2011-08-24 Samuel Colin , Howard M Wiseman

We analyse the non-relativistic approximation of the Dirac equation for slow fermions moving in spacetimes with a static metric, caused by the weak gravitational field of the Earth and a chameleon field, and derive the most general…

General Relativity and Quantum Cosmology · Physics 2015-06-19 A. N. Ivanov , M. Pitschmann

The rich structure of solid state physics provides us with Dirac materials the effective theory of which enjoys the Lorentz symmetry. In non-symmorphic lattices, the Lorentz symmetry will be deformed in a way that the null energy-momentum…

Mesoscale and Nanoscale Physics · Physics 2019-08-08 Zahra Jalali-Mola , S. A. Jafari

A system in which the free part of the action possesses a gauge symmetry that is not respected by the interacting part presents problems when quantized. We illustrate how the Dirac constraint formalism can be used to address this difficulty…

High Energy Physics - Theory · Physics 2016-06-21 F. A. Chishtie , T. Hanif , D. G. C. McKeon

We describe a new phenomenon of zitterbewegung of a free Dirac particle in cosmological spacetimes. Unlike the similar effect theorized by Schrodinger in 1930, the cosmological zitterbewegung is a real, physically attainable effect, which…

General Relativity and Quantum Cosmology · Physics 2015-06-15 Parth Girdhar , Archil Kobakhidze

We present a privileged Fock quantization of a massive Dirac field in a closed Friedmann-Robertson-Walker cosmology, partially selected by the criteria of invariance of the vacuum under the symmetries of the field equations, and unitary…

General Relativity and Quantum Cosmology · Physics 2015-11-11 Jerónimo Cortez , Beatriz Elizaga Navascués , Mercedes Martín-Benito , Guillermo A. Mena Marugán , José M. Velhinho

The general formalism of the free Dirac fermions on spatially flat $(1+3)$-dimensional Friedmann-Lema\^ itre-Robertson-Walker (FLRW) spacetimes is developed in momentum representation. The mode expansions in terms of the fundamental spinors…

General Relativity and Quantum Cosmology · Physics 2019-06-10 Ion I. Cotaescu

Tensor, matrix and quaternion formulations of Dirac-K\"ahler equation for massive and massless fields are considered. The equation matrices obtained are simple linear combinations of matrix elements in the 16-dimensional space. The…

High Energy Physics - Theory · Physics 2007-05-23 S. I. Kruglov

We show the existence of a co(dual)-BRST symmetry for the usual BRST invariant Lagrangian density of an Abelian gauge theory in two dimensions of space-time where a U(1) gauge field is coupled to the Noether conserved current (constructed…

High Energy Physics - Theory · Physics 2011-07-19 R. P. Malik

We find exact solutions to the Dirac equation in D-dimensional de Sitter spacetime. Using these solutions we analytically calculate the de Sitter quasinormal (QN) frequencies of the Dirac field. For the massive Dirac field this computation…

General Relativity and Quantum Cosmology · Physics 2008-11-26 A. Lopez-Ortega

''Massless'' spin-2 field equation in de Sitter space, which is invariant under the conformal transformation, has been obtained. The frame work utilized is the symmetric rank-2 tensor field of the conformal group. Our method is based on the…

General Relativity and Quantum Cosmology · Physics 2014-06-18 M. Dehghani , S. Rouhani , M. V. Takook , M. R. Tanhayi

Some quantum field theories described by non-Hermitian Hamiltonians are investigated. It is shown that for the case of a free fermion field theory with a $\gamma_5$ mass term the Hamiltonian is $\cal PT$-symmetric. Depending on the mass…

High Energy Physics - Theory · Physics 2015-06-26 Carl M. Bender , H. F. Jones , R. J. Rivers

Effects of the configuration of an external static magnetic field in the form of a singular vortex on the vacuum of a quantized massless spinor field are determined. The most general boundary conditions at the punctured singular point which…

High Energy Physics - Theory · Physics 2007-05-23 Yu. A. Sitenko

We show that the Dirac equation can be rewritten as a relation describing the fundamental symmetry group of special topological manifold corresponding to the Dirac wave field. It leads to unification of the time-space and internal…

Quantum Physics · Physics 2007-05-23 O. A. Olkhov