Yazar "Sahoo, P. K." seçeneğine göre listele

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    Öğe
    Magnetized strange quark matter in f(R, T) gravity with bilinear and special form of time varying deceleration parameter
    (Elsevier Science Bv, 2018) Sahoo, P. K.; Sahoo, Parbati; Bishi, Binaya K.; Aygun, Sezgin
    In this paper, we have studied homogeneous and anisotropic locally rotationally symmetric (LRS) Bianchi type-I model with magnetized strange quark matter (MSQM) distribution and cosmological constant A in f(R, T) gravity where R is the Ricci scalar and T the trace of matter source. The exact solutions of the field equations are obtained under bilinear and special form of time varying deceleration parameter (DP). Firstly, we have considered two specific forms of bilinear DP with a single parameter of the form: q = alpha(1-t/1+t) and q = -alpha t/1+t, which leads to the constant or linear nature of the function based on the constant a. Second one is the special form of the DP as q = -1 + beta/1+a(beta) From the results obtained here, one can observe that in the early universe magnetic flux has more effects and it reduces gradually in the later stage. For t -> infinity, we get p -> -Bc, and p -> B-c. The behaviour of strange quark matter along with magnetic epoch gives an idea of accelerated expansion of the universe as per the observations of the type Ia Supernovae.
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    Öğe
    Magnetized strange quark model with Big Rip singularity in f (R, T) gravity
    (World Scientific Publ Co Pte Ltd, 2017) Sahoo, P. K.; Sahoo, Parbati; Bishi, Binaya K.; Aygun, S.
    Locally rotationally symmetric (LRS) Bianchi type-I magnetized strange quark matter (SQM) cosmological model has been studied based on f(R, T) gravity. The exact solutions of the field equations are derived with linearly time varying deceleration parameter, which is consistent with observational data (from SNIa, BAO and CMB) of standard cosmology. It is observed that the model begins with big bang and ends with a Big Rip. The transition of the deceleration parameter from decelerating phase to accelerating phase with respect to redshift obtained in our model fits with the recent observational data obtained by Farook et al. [Astrophys. T. 835, 26 (2017)]. The well-known Hubble parameter H(z) and distance modulus it(z) are discussed with redshift.
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    Öğe
    Teleparallel energy-momentum distribution of various black hole and wormhole metrics
    (World Scientific Publ Co Pte Ltd, 2018) Aygün, Sezgin; Baysal, Hüsnü; Aktaş, Can; Yılmaz, İhsan; Sahoo, P. K.; Tarhan, İsmail
    Using the Einstein, Bergmann-Thomson (BT) and Landau-Lifshitz (LL) energy and momentum formulations in teleparallel gravity (TG), we obtain the total energy and momentum distributions for phantom black hole metric. We get different energy distributions similar to the earlier study and the momentum distributions vanish for phantom black hole metric in TG. These momentum solutions agree with the study of Sahoo et al. in general relativity. However, using Einstein, Bergmann-Thomson and Landau-Lifshitz energy and momentum complexes, we investigate regular black hole, asymptotically flat wormhole, anti-de Sitter wormhole and Ellis wormhole solutions in TG. We obtain i) same BT and LL energy density solutions for regular black hole metric, (ii) same and zero energy distribution for asymptotically flat wormhole, (iii) proportion with Einstein and BT energy density solutions for anti-de Sitter wormhole, (iv) same and negative Einstein and BT energy density solutions for Ellis wormhole in TG.