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Related papers: Fermions in Hybrid Loop Quantum Cosmology

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We quantize to completion an inflationary universe with small inhomogeneities in the framework of loop quantum cosmology. The homogeneous setting consists of a massive scalar field propagating in a closed, homogeneous scenario. We provide a…

General Relativity and Quantum Cosmology · Physics 2012-07-20 Mikel Fernández-Méndez , Guillermo A. Mena Marugán , Javier Olmedo

We develop a systematic classical framework to accommodate canonical quantization of geometric and matter perturbations on a quantum homogeneous isotropic flat spacetime. The existing approach of standard cosmological perturbations is…

General Relativity and Quantum Cosmology · Physics 2013-06-05 Andrea Dapor , Jerzy Lewandowski , Jacek Puchta

We study the evolution of a homogeneous and isotropic spacetime whose spatial sections have three-torus topology, coupled to a massless scalar field with small scalar perturbations within loop quantum cosmology. We consider a proposal for…

General Relativity and Quantum Cosmology · Physics 2014-12-11 Mikel Fernández-Méndez , Guillermo A. Mena Marugán , Javier Olmedo

Moving from the consideration that matter fields must be treated in terms of their fundamental quantum counterparts, we show straightforward arguments, within the framework of ordinary quantum mechanics and quantum field theory, in order to…

General Relativity and Quantum Cosmology · Physics 2016-12-28 Pietro Dona , Antonino Marciano

We quantize an inhomogeneous cosmological model using techniques that include polymeric quantization. More explicitly, we construct well defined operators to represent the constraints and find the physical Hilbert space formed by their…

General Relativity and Quantum Cosmology · Physics 2009-02-23 Mercedes Martin-Benito , Luis J. Garay , Guillermo A. Mena Marugan

We study the Fock quantization of a free Dirac field in 2+1-dimensional backgrounds which are conformally ultrastatic, with a time-dependent conformal factor. As it is typical for field theories, there is an infinite ambiguity in the Fock…

General Relativity and Quantum Cosmology · Physics 2017-09-06 Jerónimo Cortez , Beatriz Elizaga Navascués , Mercedes Martín-Benito , Guillermo A. Mena Marugán , José M. Velhinho

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

The quantum evolution equation of Loop Quantum Cosmology (LQC) -- the quantum Hamiltonian constraint -- is a difference equation. We relate the LQC constraint equation in vacuum Bianchi I separable (locally rotationally symmetric) models…

General Relativity and Quantum Cosmology · Physics 2013-01-25 Christine C. Dantas

We consider the time evolution of systems in which a spatially homogeneous scalar field is coupled to fermions. The quantum back-reaction is taken into account in one-loop approximation. We set up the basic equations and their…

High Energy Physics - Phenomenology · Physics 2016-09-06 Juergen Baacke , Katrin Heitmann , Carsten Patzold

The light-front (LF) canonical quantization of quantum chromodynamics in covariant gauge is discussed. The Dirac procedure is used to eliminate the constraints in the gauge-fixed front form theory quantum action and to construct the LF…

High Energy Physics - Phenomenology · Physics 2009-09-11 Prem P. Srivastava , Stanley J. Brodsky

We study a formulation of Dirac fermions in curved spacetime that respects general coordinate invariance as well as invariance under local spin-base transformations. The natural variables for this formulation are spacetime-dependent Dirac…

High Energy Physics - Theory · Physics 2014-03-26 Holger Gies , Stefan Lippoldt

The phenomenon of particle production for quantum field theories in curved spacetimes is crucial to understand the large-scale structure of a universe from an inflationary epoch. In contrast to the free and fixed-background case, the…

General Relativity and Quantum Cosmology · Physics 2025-12-04 Carlos Fulgado-Claudio , Pablo Sala , Daniel González-Cuadra , Alejandro Bermudez

Presented is a quantum lattice gas algorithm to efficiently model a system of Dirac particles interacting through an intermediary gauge field. The algorithm uses a fixed qubit array to represent both the spacetime and the particles…

Quantum Physics · Physics 2017-02-01 Jeffrey Yepez

We address the issue of the infinite ambiguity that affects the construction of a Fock quantization of a Dirac field propagating in a cosmological spacetime with flat compact sections. In particular, we discuss a physical criterion that…

General Relativity and Quantum Cosmology · Physics 2017-03-08 Jerónimo Cortez , Beatriz Elizaga Navascués , Mercedes Martín-Benito , Guillermo A. Mena Marugán , José M. Velhinho

The first-order loop quantum gravity correction of the simplest, classical general-relativistic Friedmann Hamiltonian constraint, emerging from a holomorphic spinfoam cosmological model peaked on homogeneous, isotropic geometries, is…

General Relativity and Quantum Cosmology · Physics 2015-07-02 Christian Röken

The restriction to invariant connections in a Friedmann-Robertson-Walker space-time is discussed via the analysis of the Dirac brackets associated with the corresponding gauge fixing. This analysis allows us to establish the proper…

General Relativity and Quantum Cosmology · Physics 2015-05-27 Francesco Cianfrani , Giovanni Montani

For the description of space-time fermions, Dirac-K\"ahler fields (inhomogeneous differential forms) provide an interesting alternative to the Dirac spinor fields. In this paper we develop a similar concept within the symplectic geometry of…

High Energy Physics - Theory · Physics 2009-10-31 M. Reuter

We develop a complete Hamiltonian approach to the theory of perturbations around any spatially homogeneous spacetime. We employ the Dirac method for constrained systems which is well-suited to cosmological perturbations. We refine the…

General Relativity and Quantum Cosmology · Physics 2023-01-19 Alice Boldrin , Przemysław Małkiewicz

Nowadays, quantum simulation schemes come in two flavours. Either they are continuous-time discrete-space models (a.k.a Hamiltonian-based), pertaining to non-relativistic quantum mechanics. Or they are discrete-spacetime models (a.k.a…

Quantum Physics · Physics 2019-10-18 Giuseppe Di Molfetta , Pablo Arrighi

We estimate fermion loop corrections to the two-point correlation function of primordial tensor perturbations in a slow-roll inflationary background. We particularly compute an explicit term of one-loop correction from a massless fermion,…

High Energy Physics - Theory · Physics 2012-11-22 Kaixi Feng , Yi-Fu Cai , Yun-Song Piao