Einstein field equations are considered in zero-curvature Robertson–Walker (R–W) cosmology with perfect fluid source and time-dependent gravitational and cosmological “constants.” Exact solutions of the field equations are obtained by using the ’gamma-law' equation of state p = (γ − 1)ρ in which γ varies continuously with cosmological time. The functional form of γ (R) is used to analyze a wide range of cosmological solutions at early universe for two phases in cosmic history: inflationary phase and Radiation-dominated phase. The corresponding physical interpretations of the cosmological solutions are also discussed.
Article PDF
Similar content being viewed by others
Avoid common mistakes on your manuscript.
References
Abdel-Rahman, A. M. M. (1992). Physical Review D 45, 3497.
Abdusstar and Vishwakarma, R. G. (1997). Australian Journal of Physics 50, 893.
Beesham, A. (1986). International Journal of Theoretical Physics 25, 1295.
Berman, M. S. (1991). General Relativity and Gravitation 23, 465.
Canuto, V., Adams, R. H., Hsieh, S. H., and Tsiang, E. (1977a). Physical Review D, 16, 1643.
Canuto, V., Hsich, S. H., and Adams, P. J. (1977b). Physics Letters 39, 429.
Carvalho, J. C. (1996). International Journal of Theoretical Physics 35, 2019.
Chen, W. and Wu, Y. S. (1990). Physical Review D 41, 695.
DerSarkissian, M. (1985). Nuovo Cimento B 88, 29.
Dicke, R. H. (1961). Nature (London) 192, 440.
Dirac, P. A. M. (1937a). Nature (London) 139, 323.
Dirac, P. A. M. (1937b). Nature (London) 139, 1001.
Dirac, P. A. M. (1938). Proceeding of Royal Society London 165, 199.
Fulling, S. A., Parker, L., and Hu, B. L. (1974). Physical Review D 10, 3905.
Kalligas, D., Wesson, P., and Everitt, C. W. F. (1992). General Relativity and Gravitation 24, 351.
Lau, Y. K. (1985). Austrian Journal of Physics 38, 547.
Levit, L. S. (1980). Letter Nuovo Cimento 29, 23.
Lima, J. A. S. and Carvalho, J. C. (1994). General Relativity and Gravitation 26, 909.
Lima, J. A. S. and Maia, J. M. F. (1993). Modern Physics Letter A 48, 591.
Ray Chaudhari, A. K. (1979). Theoretical Cosmology, Clarendon Press, Oxford.
Sistero, R. F. (1991). General Relativity and Gravitation, 23, 1265.
Weinberg, S. (1972). Gravitation and Cosmology, Wiley, New York.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Singh, C.P. Early Universe with Variable Gravitational and Cosmological Constants. Int J Theor Phys 45, 519–528 (2006). https://doi.org/10.1007/s10773-006-9035-1
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s10773-006-9035-1