Implications of Raychaudhuri equation and geodesic focusing in interacting two fluid systems

Abstract The present work analyses Raychaudhuri equation (RE) in Einstein gravity for two interacting fluids. Focusing theorem, a consequence of RE, is directly related to the singularity theorems of Penrose and Hawking. In the present work, the signature of the Raychaudhuri scalar or convergence sc...

Full description

Saved in:
Bibliographic Details
Main Authors: Madhukrishna Chakraborty, Subenoy Chakraborty
Format: Article
Language:English
Published: SpringerOpen 2025-01-01
Series:European Physical Journal C: Particles and Fields
Online Access:https://doi.org/10.1140/epjc/s10052-025-13850-6
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1832571413854158848
author Madhukrishna Chakraborty
Subenoy Chakraborty
author_facet Madhukrishna Chakraborty
Subenoy Chakraborty
author_sort Madhukrishna Chakraborty
collection DOAJ
description Abstract The present work analyses Raychaudhuri equation (RE) in Einstein gravity for two interacting fluids. Focusing theorem, a consequence of RE, is directly related to the singularity theorems of Penrose and Hawking. In the present work, the signature of the Raychaudhuri scalar or convergence scalar has been examined for two types of interaction forms namely, (i) $$Q=H(\alpha \rho _1+\beta \rho _2)$$ Q = H ( α ρ 1 + β ρ 2 ) (linear) and (ii) $$Q=\dfrac{H\xi \rho _1\rho _2}{\alpha \rho _1+\beta \rho _2}$$ Q = H ξ ρ 1 ρ 2 α ρ 1 + β ρ 2 (non-linear). Finally, the phenomena of focusing of a congruence of geodesics and possible avoidance of singularity have been discussed based on the nature of the two fluids and the interaction term operating between them.
format Article
id doaj-art-e95373d181794eb6b813c22d87664f3b
institution Kabale University
issn 1434-6052
language English
publishDate 2025-01-01
publisher SpringerOpen
record_format Article
series European Physical Journal C: Particles and Fields
spelling doaj-art-e95373d181794eb6b813c22d87664f3b2025-02-02T12:38:14ZengSpringerOpenEuropean Physical Journal C: Particles and Fields1434-60522025-01-0185111010.1140/epjc/s10052-025-13850-6Implications of Raychaudhuri equation and geodesic focusing in interacting two fluid systemsMadhukrishna Chakraborty0Subenoy Chakraborty1Department of Mathematics, Techno India UniversityDepartment of Mathematics, Brainware UniversityAbstract The present work analyses Raychaudhuri equation (RE) in Einstein gravity for two interacting fluids. Focusing theorem, a consequence of RE, is directly related to the singularity theorems of Penrose and Hawking. In the present work, the signature of the Raychaudhuri scalar or convergence scalar has been examined for two types of interaction forms namely, (i) $$Q=H(\alpha \rho _1+\beta \rho _2)$$ Q = H ( α ρ 1 + β ρ 2 ) (linear) and (ii) $$Q=\dfrac{H\xi \rho _1\rho _2}{\alpha \rho _1+\beta \rho _2}$$ Q = H ξ ρ 1 ρ 2 α ρ 1 + β ρ 2 (non-linear). Finally, the phenomena of focusing of a congruence of geodesics and possible avoidance of singularity have been discussed based on the nature of the two fluids and the interaction term operating between them.https://doi.org/10.1140/epjc/s10052-025-13850-6
spellingShingle Madhukrishna Chakraborty
Subenoy Chakraborty
Implications of Raychaudhuri equation and geodesic focusing in interacting two fluid systems
European Physical Journal C: Particles and Fields
title Implications of Raychaudhuri equation and geodesic focusing in interacting two fluid systems
title_full Implications of Raychaudhuri equation and geodesic focusing in interacting two fluid systems
title_fullStr Implications of Raychaudhuri equation and geodesic focusing in interacting two fluid systems
title_full_unstemmed Implications of Raychaudhuri equation and geodesic focusing in interacting two fluid systems
title_short Implications of Raychaudhuri equation and geodesic focusing in interacting two fluid systems
title_sort implications of raychaudhuri equation and geodesic focusing in interacting two fluid systems
url https://doi.org/10.1140/epjc/s10052-025-13850-6
work_keys_str_mv AT madhukrishnachakraborty implicationsofraychaudhuriequationandgeodesicfocusingininteractingtwofluidsystems
AT subenoychakraborty implicationsofraychaudhuriequationandgeodesicfocusingininteractingtwofluidsystems