On LRS Space-Times Admitting Conformal Motions
Abstract
1. Introduction
2. Version of Model
- The contravariant and covariant components of the four-velocity vector field can be defined by , and they are verified as .
- The volume and the average scale factor are given by
- The acceleration vector field is
- The rotation tensor is defined as
- The expansion rate and the Hubble parameter H are given by
- The average anisotropy parameter , and the deceleration parameter q are
- The shear scalar can also be defined as follows:The non-zero components of the shear tensor are given by
3. Conformal Killing Equations and Their Solution
4. Perfect Fluid Solutions of Einstein’s Field Equations
5. Kinematic Variables
6. Conclusions
Author Contributions
Funding
Data Availability Statement
Conflicts of Interest
References
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Classification | Vector Field | Scale Factors | Line Element | Physical Properties |
---|---|---|---|---|
Conformal solution | CKV (41) | Equation (42), with | ||
Conformal solution | CKV (43) | Equation (44), with | ||
Conformal solution | CKV (45) | Equation (46), with | ||
Self-similar solution | HV (49) | |||
Self-similar solution |
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Gad, R.M.; Al-Jedani, A.; Alsulami, S.T. On LRS Space-Times Admitting Conformal Motions. Symmetry 2025, 17, 1241. https://doi.org/10.3390/sym17081241
Gad RM, Al-Jedani A, Alsulami ST. On LRS Space-Times Admitting Conformal Motions. Symmetry. 2025; 17(8):1241. https://doi.org/10.3390/sym17081241
Chicago/Turabian StyleGad, Ragab M., Awatif Al-Jedani, and Shahad T. Alsulami. 2025. "On LRS Space-Times Admitting Conformal Motions" Symmetry 17, no. 8: 1241. https://doi.org/10.3390/sym17081241
APA StyleGad, R. M., Al-Jedani, A., & Alsulami, S. T. (2025). On LRS Space-Times Admitting Conformal Motions. Symmetry, 17(8), 1241. https://doi.org/10.3390/sym17081241