TARU PUBLICATIONS
Journal of Interdisciplinary Mathematics cover
Open Access ·Peer-reviewed·ISSN (Online): 2169-012X·ISSN (Print): 0972-0502

Monthly Journal: Publishes the methodological and theoretical role of mathematics and mathematical applications underpinning scientific research.

Issues up to 2022 co-published with and available at:Taylor & Francis Online
submissions@tarupublications.com
Open Access Research Article

Bianchi type-VI0 string cosmological model in Saez Ballester theory with variable Λ

, * , ,

* Corresponding author · click or hover a name for details

pp. 2319–2329Vol. 28Issue 6September 2025DOI: 10.47974/JIM-2374XML
Received:
10 Dec 2024
Published Online:
30 Sep 2025
Article type:
Research Article
Language:
EN
Article no.:
JIM-2374
Pages:
2319–2329

Abstract

This work is the result of examining Bianchi VI_0 string cosmology model, including the Saez-Ballester theory (SBT) of gravity & varying cosmological constant. Energy-momentum tensor developed by Letelier [1] for such strings is utilized for constructing massive string cosmic models. We presumed that the model’s expansion (θ) scales with the shear tensor (σij) component σ11 and solution to Einstein’s field equations (EFE) has been procured using a functional relationship based on the Hubble parameter H. This leads to a model of the cosmos in which the expansion is initially decelerated but later accelerates up. Research indicates that strings predominated in the early cosmos until eventually vanishing for sufficiently long periods of time, which is consistent with observations made by astronomers today. The model’s geometrical and physical characteristics are also thoroughly covered.

Keywords

Subject Classifications

83C15

References

[1] P. S. Letelier, “String cosmologies”, Physical review D, vol. 28, no. 10, pp. 2414-2419, (1983).
[2] T. W. B. Kibble, and N. Turok, “Self-intersection of cosmic strings”, Physics Letters B, vol. 116, no. 2-3, pp. 141-143, (1982).
[3] P. S. Letelier, “Clouds of strings in general relativity”, Physical Review D, vol. 20, no. 6, pp. 1294-1302, (1979).
[4] J. Stachel, “Thickening the string. I. The string perfect dust”, Physical Review D, vol. 21, no. 8, pp. 2171-2181, (1980).
[5] A. E. Everett, “Cosmic strings in unified gauge theories”, Physical Review D, vol. 24, no. 4, pp. 858-868, (1981).
[6] A. Vilenkin, “Gravitational field of vacuum domain walls and strings”, Physical Review D, vol. 23, no. 4, pp. 852-857, (1981).
[7] M. Vijaya Santhi, V. U. M. Rao, and Y. Aditya, “Bianchi type-I bulk viscous string model in f (R) gravity”, Journal of Dynamical Systems and Geometric Theories, vol. 17, no. 1, pp. 23-38, (2019).
[8] R. Bali, and Anjali, “Bianchi type I magnetized string cosmological model in general relativity”, Astrophysics and space Science, vol. 302, pp. 201-205, (2006).
[9] K. S. Adhav, M. V. Dawande, and V. B. Raut, “Bianchi Type-III String Cosmological Models”, International Journal of Theoretical Physics, vol. 48, pp. 700-705, (2009).
[10] A. M. Al-Haysah, and A. H. Hasmani, “Higher dimensional Bianchi type-I string cosmological model in f (R) theory of gravity”, Heliyon, vol. 7, no. 9, (2021).
[11] A. Singh, “String LRS Bianchi type I universe with functional relation on Hubble parameter”, Indian Journal of Physics, pp. 1-7, (2024).
[12] S. Kumawat and L. Poonia, “Homogeneous barotropic string cosmology model of Bianchi type VI0 in general relativity”, (2023).
[13] C. Brans and R. H. Dicke, “Mach’s principle and a relativistic theory of gravitation”, Physical review, vol. 124, no. 3, (1961).
[14] K. Nordtvedt Jr, “Post-Newtonian Metric for a General Class of Scalar-Tensor Gravitational Theories and Observational Consequences”, Astrophysical Journal, vol. 161, pp. 1059-1067, (1970).
[15] G. A. Barber, “On two “self-creation” cosmologies”, General Relativity and Gravitation, vol. 14, pp. 117-136, (1982).
[16] D. Saez and V. J. Ballester, “A simple coupling with cosmological implications”, Physics Letters A, vol. 113, no. 9, pp. 467-470, (1986).
[17] C. P. Singh, M. Zeyauddin, and S. Ram, “Anisotropic Bianchi-V cosmological models in Saez–Ballester theory of gravitation”, International Journal of Modern Physics A, vol. 23, no. 18, pp. 2719-2731, (2008).
[18] S. Ram, M. Zeyauddin, and C. P. Singh, “Bianchi type-V cosmological models with perfect fluid and heat flow in Saez-Ballester theory”, Pramana, vol. 72, pp. 415-427, (2009).
[19] J. Socorro, P. A. Rodríguez, A. Espinoza-García, L. O. Pimentel, and P. Romero, “Cosmological Bianchi class A models in Sáez-Ballester theory”, In Aspects of Today’s Cosmology, pp. 185-204, (2011).
[20] R. K. Mishra, and A. Chand, “Cosmological models in Sáez-Ballester theory with bilinear varying deceleration parameter”, Astrophysics and Space Science, vol. 365, no. 4, (2020).
[21] R. K. Mishra, and H. Dua, “Bianchi type-I cosmological model in Sáez-Ballester theory with variable deceleration parameter”, Astrophysics and Space Science, vol. 366, no. 5, (2021).
[22] R. K. Dabgar, and A. K. Bhabor, “Higher dimensional Bianchi type-III string cosmological models with dark energy in Saez–Ballester scalar-tensor theory of gravitation”, Journal of Astrophysics and Astronomy, vol. 44, no. 2, (2023).
[23] B. K. Shukla, S. Khare, S. N. Shukla, and A. Singh, “Bianchi Type-I Cosmological Model in Saez-Ballester Theory with Varying Cosmological Constant”, Prespacetime Journal, vol. 13, no. 3, (2022).
[24] N. Sugiyama, and K. Sato, “Constraints on cosmological models with the decaying cosmological constant from cosmic background radiation anisotropies”, Astrophysical Journal, vol. 387, pp. 439-442, (1992).
[25] B. Ratra, and A. Quillen, “Gravitational lensing effects in a time-variable cosmological ‘constant’cosmology”, Monthly Notices of the Royal Astronomical Society, vol. 259, no. 4, pp. 738-742, (1992).
[26] S. M. Barr, “Attempt at a classical cancellation of the cosmological constant”, Physical Review D, vol. 36, no. 6, pp. 1691-1700, (1987).
[27] R. Bali, and S. Saraf, “C-field cosmological model for barotropic fluid distribution with varying Λ in FRW space time”, International Journal of Theoretical Physics, vol. 52, no. 5, pp. 1645-1653, (2013).
[28] B. K. Shukla, S. Khare, S. N. Shukla, and A. Singh, “Bianchi Type-I Cosmological Model in Saez-Ballester Theory with Varying Cosmological Constant”, Prespacetime Journal, vol. 13, no. 3, (2022).
[29] S. Sen, G. S. Khadekar, and S. Samdurkar, “Bulk Viscous Bianchi Type-III Cosmological Model with Modified Takabayasi String in the Presence of Varying Λ”, Journal of Dynamical Systems and Geometric Theories, vol. 19, no. 1, pp. 95-112, (2021).
[30] J. P. Singh, “A cosmological model with both deceleration and acceleration”, Astrophysics and space science, vol. 318, no. 1, pp. 103-107, (2008).
[31] A. I. Arbab, “FRW-type universe with vacuum energy density”, arXiv preprint gr-qc/9906045, (1999).

Views: 125Downloads: 94Citations: 0