The Raychaudhuri equation in homogeneous cosmologies

In this work we address the issue of studying the conditions required to guarantee the Focusing Theorem for both null and time like geodesic congruences by using the Raychaudhuri equation. In particular we study the case of Friedmann-Robertson-Walker as well as more general Bianchi Type I spacetimes...

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Detalhes bibliográficos
Autores: Albareti, F. D., Ruiz Cembranos, José Alberto, Cruz Dombriz, Álvaro de la, Dobado González, Antonio
Formato: artículo
Fecha de publicación:2014
País:España
Recursos:Universidad Complutense de Madrid (UCM)
Repositorio:Docta Complutense
Idioma:inglés
OAI Identifier:oai:docta.ucm.es:20.500.14352/35052
Acesso em linha:https://hdl.handle.net/20.500.14352/35052
Access Level:acceso abierto
Palavra-chave:53
R-n-gravity
Dark energy
Relativistic theory
Machs principle
Cpt violation
Supergravity
Supersymmetry
Supernovae
Constant
Geometry
Física (Física)
22 Física
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oai_identifier_str oai:docta.ucm.es:20.500.14352/35052
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repository_id_str
spelling The Raychaudhuri equation in homogeneous cosmologiesAlbareti, F. D.Ruiz Cembranos, José AlbertoCruz Dombriz, Álvaro de laDobado González, Antonio53R-n-gravityDark energyRelativistic theoryMachs principleCpt violationSupergravitySupersymmetrySupernovaeConstantGeometryFísica (Física)22 FísicaIn this work we address the issue of studying the conditions required to guarantee the Focusing Theorem for both null and time like geodesic congruences by using the Raychaudhuri equation. In particular we study the case of Friedmann-Robertson-Walker as well as more general Bianchi Type I spacetimes. The fulfillment of the Focusing Theorem is mandatory in small scales since it accounts for the attractive character of gravity. However, the Focusing Theorem is not satisfied at cosmological scales due to the measured negative deceleration parameter. The study of the conditions needed for congruences convergence is not only relevant at the fundamental level but also to derive the viability conditions to be imposed on extended theories of gravity describing the different expansion regimes of the universe. We illustrate this idea for f (R) gravity theories.Iop PublishingUniversidad Complutense de Madrid20142014-01-0120142014-01-01journal articlehttp://purl.org/coar/resource_type/c_6501info:eu-repo/semantics/articleapplication/pdfhttps://hdl.handle.net/20.500.14352/35052reponame:Docta Complutenseinstname:Universidad Complutense de Madrid (UCM)Inglésengopen accesshttp://purl.org/coar/access_right/c_abf2info:eu-repo/semantics/openAccessoai:docta.ucm.es:20.500.14352/350522026-06-02T12:44:21Z
dc.title.none.fl_str_mv The Raychaudhuri equation in homogeneous cosmologies
title The Raychaudhuri equation in homogeneous cosmologies
spellingShingle The Raychaudhuri equation in homogeneous cosmologies
Albareti, F. D.
53
R-n-gravity
Dark energy
Relativistic theory
Machs principle
Cpt violation
Supergravity
Supersymmetry
Supernovae
Constant
Geometry
Física (Física)
22 Física
title_short The Raychaudhuri equation in homogeneous cosmologies
title_full The Raychaudhuri equation in homogeneous cosmologies
title_fullStr The Raychaudhuri equation in homogeneous cosmologies
title_full_unstemmed The Raychaudhuri equation in homogeneous cosmologies
title_sort The Raychaudhuri equation in homogeneous cosmologies
dc.creator.none.fl_str_mv Albareti, F. D.
Ruiz Cembranos, José Alberto
Cruz Dombriz, Álvaro de la
Dobado González, Antonio
author Albareti, F. D.
author_facet Albareti, F. D.
Ruiz Cembranos, José Alberto
Cruz Dombriz, Álvaro de la
Dobado González, Antonio
author_role author
author2 Ruiz Cembranos, José Alberto
Cruz Dombriz, Álvaro de la
Dobado González, Antonio
author2_role author
author
author
dc.contributor.none.fl_str_mv Universidad Complutense de Madrid
dc.subject.none.fl_str_mv 53
R-n-gravity
Dark energy
Relativistic theory
Machs principle
Cpt violation
Supergravity
Supersymmetry
Supernovae
Constant
Geometry
Física (Física)
22 Física
topic 53
R-n-gravity
Dark energy
Relativistic theory
Machs principle
Cpt violation
Supergravity
Supersymmetry
Supernovae
Constant
Geometry
Física (Física)
22 Física
description In this work we address the issue of studying the conditions required to guarantee the Focusing Theorem for both null and time like geodesic congruences by using the Raychaudhuri equation. In particular we study the case of Friedmann-Robertson-Walker as well as more general Bianchi Type I spacetimes. The fulfillment of the Focusing Theorem is mandatory in small scales since it accounts for the attractive character of gravity. However, the Focusing Theorem is not satisfied at cosmological scales due to the measured negative deceleration parameter. The study of the conditions needed for congruences convergence is not only relevant at the fundamental level but also to derive the viability conditions to be imposed on extended theories of gravity describing the different expansion regimes of the universe. We illustrate this idea for f (R) gravity theories.
publishDate 2014
dc.date.none.fl_str_mv 2014
2014-01-01
2014
2014-01-01
dc.type.none.fl_str_mv journal article
http://purl.org/coar/resource_type/c_6501
dc.type.openaire.fl_str_mv info:eu-repo/semantics/article
format article
dc.identifier.none.fl_str_mv https://hdl.handle.net/20.500.14352/35052
url https://hdl.handle.net/20.500.14352/35052
dc.language.none.fl_str_mv Inglés
eng
language_invalid_str_mv Inglés
language eng
dc.rights.none.fl_str_mv open access
http://purl.org/coar/access_right/c_abf2
dc.rights.openaire.fl_str_mv info:eu-repo/semantics/openAccess
rights_invalid_str_mv open access
http://purl.org/coar/access_right/c_abf2
eu_rights_str_mv openAccess
dc.format.none.fl_str_mv application/pdf
dc.publisher.none.fl_str_mv Iop Publishing
publisher.none.fl_str_mv Iop Publishing
dc.source.none.fl_str_mv reponame:Docta Complutense
instname:Universidad Complutense de Madrid (UCM)
instname_str Universidad Complutense de Madrid (UCM)
reponame_str Docta Complutense
collection Docta Complutense
repository.name.fl_str_mv
repository.mail.fl_str_mv
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score 15,300724

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