1995 (IPP)
Permanent URI for this collectionhttp://localhost:4000/handle/11007/2812
Browse
4 results
Search Results
Item Inhomogeneous cosmological models with heat flux(2015-02-07) Patel, L.K.; Tikekar, R.; Dadhich, NareshWe present a general class of inhomogeneous cosmological models filled with non-thermalized perfect fluid by assuming that the background spacetime admits two space-like commuting Killing vectors and has separable metric coefficients. The singularity structure of these models depends on the choice of the parameters and the metric functions, A number of previously known perfect fluid models follow as particular cases of this general class. Physical and geometrical features of these models are studied and the general expression for temperature distribution is givenItem String-dust in Einstein and godel universes(2015-01-27) Dadhich, Naresh; Patel, L.K.We consider the mixture of perfect fluid and string-dust and obtain string-dust generalization of the Einstein and godel universes.Item The role of shear in expanding cylindrical perfect fluid models(2015-01-27) Dadhich, Naresh; Patel, L.K.For orthogonal cylindrically symmetric expanding perfect fluid spacetime we prove that vanishing of shear implies vanishing of acceleration which further renders spacetime homogeneous. That means inhomogeneous spacetimes must always be shearing and anisotropic. Non-singular spacetimes will thus be both inhomogeneous and anisotropic.Item Cylindrically symmetric cosmological models in the Kaluza-Klein space time(2015-01-27) Patel, L.K.; Dadhich, NareshWe consider a non-diagonal cylindrically symmetric metric in the Kaluza-Klein spacetime. We obtain a number of homogeneous and inhomogeneous perfect fluid cosmological models, which include the 5-dimensional analogue of the recently found 4-dimensional non-singular stiff fluid model. Amongst the homogeneous models, which are all as expected big-bang singular, there is the 5-dimensional version of the Friedman-Robertson-Walker flat model.