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Related papers: Polarized Dirac fermions in de Sitter spacetime

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Starting with a new theory of symmetries generated by isometries in field theories with spin, one finds the generators of the spinor representation in backgrounds with a given symmetry. In this manner one obtains a collection of conserved…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Ion I Cotăescu

Relativistic spin-1/2 particles in curved spacetime are naturally described by Dirac theory, which is a dynamical and Lorentz-invariant field theory. In this work, we propose a non-dynamical fermion theory in 3+1 dimensions dubbed spinor…

High Energy Physics - Theory · Physics 2016-07-20 Giandomenico Palumbo

Quantum field theories on de Sitter spacetime with global U(1) gauge symmetry are deformed using the joint action of the internal symmetry group and a one-parameter group of boosts. The resulting theory turns out to be wedge-local and…

Mathematical Physics · Physics 2011-11-03 Eric Morfa-Morales

The discrete symmetries of the Dirac field on the de Sitter manifold are studied taking into account that this has two portions that can play the role of physical space-times, namely the expanding and a collapsing universes. The proper…

General Relativity and Quantum Cosmology · Physics 2023-01-10 Ion I. Cotaescu , Ion Cotaescu

A field-theoretical space-time position operator can be properly introduced for the Dirac field, it plays the role of a generalized Noether charge associated with a local symmetry, and its second-quantized form shows that quantum fields…

Quantum Physics · Physics 2011-01-12 Zhi-Yong Wang , Cai-Dong Xiong , Bing He

We present a fermion model characterized by an anticommuting-parameter shift symmetry. The Hamiltonian formulation exhibits a combination of first-class and second-class constraints. We derive the well-known Dirac equation by fixing the…

High Energy Physics - Theory · Physics 2023-06-30 Mauricio Valenzuela

Recently a new time-evolution picture of the Dirac quantum mechanics was defined in charts with spatially flat Robertson-Walker metrics, under the name of Schr\"{o}dinger picture [I. I. Cot\u{a}escu, arXiv:0708.0734] . In the present paper…

General Relativity and Quantum Cosmology · Physics 2008-12-18 Ion I. Cotăescu

In this paper, we present a new theoretical scenario in which both dynamical Dirac fermions and Einstein's gravity with a positive cosmological constant and torsion emerge via a spontaneous symmetry breaking in a topological phase. This…

High Energy Physics - Theory · Physics 2023-06-01 Giandomenico Palumbo

The properties of the covariant quantum fields on de Sitter spacetimes are investigated focusing on the isometry generators and Casimir operators in order to establish the equivalence among the covariant representations and the unitary…

General Relativity and Quantum Cosmology · Physics 2022-07-14 Ion I. Cotaescu

It is shown how can be derived the normalized energy eigenspinors of the free Dirac field on anti-de Sitter spacetime, by using a Cartesian tetrad gauge where the separation of spherical variables can be done like in special relativity.

General Relativity and Quantum Cosmology · Physics 2009-10-31 Ion I. Cotăescu

Connection of the invariant Dirac equation over the de Sitter space with irreducible representations of the de Sitter group is ascertained. The set of solutions of this equation is obtained in the form of the product of two different…

High Energy Physics - Theory · Physics 2007-05-23 Semyon Pol'shin

Dirac operators on curved space-times are introduced with the help of a new point-view that observers have to be included in the formulation of natural laws. The class of Dirac operators are Lorentz invariant in the sense that the…

General Relativity and Quantum Cosmology · Physics 2024-02-06 Zhongmin Qian

We discuss the dynamics of the Dirac fermions in the general strong gravitational and electromagnetic fields. We derive the general Hermitian Dirac Hamiltonian and transform it to the Foldy-Wouthuysen representation for the spatially…

High Energy Physics - Theory · Physics 2011-08-08 Yuri N. Obukhov , Alexander J. Silenko , Oleg. V. Teryaev

As a sequel to our previous work\cite{Feng2020}, we propose in this paper a quantization scheme for Dirac field in de Sitter spacetime. Our scheme is covariant under both general transformations and Lorentz transformations. We first present…

High Energy Physics - Theory · Physics 2023-09-06 Sze-Shiang Feng , Mogus Mochena

On a static spacetime, the solutions of the Dirac equation are generated by a time-independent Hamiltonian. We study this Hamiltonian and characterize the split into positive and negative energy. We use it to find explicit expressions for…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Wei Min Jin

The relativistic Dirac equation in four-dimensional spacetime reveals a coherent relation between the dimensions of spacetime and the degrees of freedom of fermionic spinors. A massless Dirac fermion generates new symmetries corresponding…

High Energy Physics - Theory · Physics 2017-09-01 Yue-Liang Wu

By using a framework where the object of noncommutativity $\theta^{\mu\nu}$ represents independent degrees of freedom, we study the symmetry properties of an extended $x+\theta$ space-time, given by the group $P$', which has the…

High Energy Physics - Theory · Physics 2009-11-13 Ricardo Amorim

We study the vacuum polarisation effects of the Dirac fermionic field induced by a pointlike global monopole located in the cosmological de Sitter spacetime. First we derive the four orthonormal Dirac modes in this background in a closed…

High Energy Physics - Theory · Physics 2022-03-25 Md Sabir Ali , Sourav Bhattacharya

In this paper, it is shown that the covariant representation (CR) transforming the Dirac field under de Sitter isometries is equivalent to a direct sum of two unitary irreducible representations (UIRs) of the $Sp(2,2)$ group transforming…

General Relativity and Quantum Cosmology · Physics 2015-11-12 Ion I. Cotaescu , Doru-Marcel Baltateanu

The theory of the free Maxwell field in two moving frames on the de Sitter spacetime is investigated pointing out that the conserved momentum and energy operators do not commute to each other. This leads us to consider new plane waves…

General Relativity and Quantum Cosmology · Physics 2011-03-15 Ion I. Cotaescu , Cosmin Crucean
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