Physics
Scientific paper
Mar 2011
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2011ijtp...50..916p&link_type=abstract
International Journal of Theoretical Physics, Volume 50, Issue 3, pp.916-933
Physics
3
String, Bianchi-I Universe, Lyra'S Manifold, Hubble'S Parameter
Scientific paper
The present study deals with a spatially homogeneous and anisotropic Bianchi type-I (B-I) cosmological models representing massive strings in normal gauge for Lyra's manifold by applying the variation law for generalized Hubble's parameter that yields a constant value of deceleration parameter. The variation law for Hubble's parameter generates two types of solutions for the average scale factor, one is of power-law type and other is of the exponential-law type. Using these two forms, Einstein's modified field equations are solved separately that correspond to expanding singular and non-singular models of the universe respectively. The energy-momentum tensor for such string as formulated by Letelier, P.S.: Phys. Rev. D 28, 2414 (1983) is used to construct massive string cosmological models for which we assume that the expansion ( θ) in the model is proportional to the component σ1_{ 1} of the shear tensor σj_{ i}. This condition leads to A=( BC) m , where A, B and C are the metric coefficients and m is proportionality constant. Our models are in accelerating phase which is consistent to the recent observations. It has been found that the displacement vector β behaves like cosmological term Λ in the normal gauge treatment and the solutions are consistent with recent observations of SNe Ia. It has been found that massive strings dominate in the both decelerating and accelerating universes. The strings dominate in the early universe and eventually disappear from the universe for sufficiently large times. This is in consistent with the current observations. Some physical and geometric behaviour of these models are also discussed.
Pradhan Anirudh
Singh Ajay Kumar
No associations
LandOfFree
Anisotropic Bianchi Type-I String Cosmological Models in Normal Gauge for Lyra's Manifold with Constant Deceleration Parameter does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Anisotropic Bianchi Type-I String Cosmological Models in Normal Gauge for Lyra's Manifold with Constant Deceleration Parameter, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Anisotropic Bianchi Type-I String Cosmological Models in Normal Gauge for Lyra's Manifold with Constant Deceleration Parameter will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-864673