scholarly journals Brans-Dicke scalar field cosmological model in Lyra’s geometry

2019 ◽  
Vol 100 (2) ◽  
Author(s):  
Dinesh Chandra Maurya ◽  
Rashid Zia
Keyword(s):  
Scalar Field ◽  
Cosmological Model ◽  
Lyra’S Geometry

Brans–Dicke scalar field cosmological model in Lyra’s geometry with time-dependent deceleration parameter

2018 ◽  
Vol 15 (11) ◽  
pp. 1850186
Author(s):  
Rashid Zia ◽  
Dinesh Chandra Maurya
Keyword(s):  
Scalar Field ◽  
Cosmological Model ◽  
Deceleration Parameter ◽  
Momentum Tensor ◽  
Energy Conditions ◽  
Physical Parameters ◽  
Type I ◽  
Field Equations ◽  
Modified Gravity Theory ◽  
Lyra’S Geometry

From the recent observations, it is well known that the expansion rate of our universe varies with time (early decelerating and accelerating in the present epoch) which is an unsolved problem. This motivated to us to consider this paper and so we have developed a new cosmological model in Einstein’s modified gravity theory using two types of modifications: (i) Geometrical modification, in which we have used Lyra’s geometry in the curvature part of the Einstein field equations (EFE) and (ii) Modification in gravity (energy momentum tensor) on right hand side of EFE, as per the Brans–Dicke model. With these two modifications, we have obtained the exact solutions of Einstein Brans–Dicke field equations in Lyra’s geometry for a spatially homogeneous Bianchi type-I space-time with time variable deceleration parameter (DP). We have calculated various physical parameters for the model and found them consistent with recent observations. We have also examined the energy conditions for the model and found them satisfactory. We have found that the scalar field of Brans–Dicke theory behaves like a best fit dark energy candidate in the reference of Lyra’s geometry.

scholarly journals INHOMOGENEOUS COSMOLOGICAL MODEL IN LYRA GEOMETRY

2002 ◽  
Vol 11 (09) ◽  
pp. 1501-1504 ◽  
Author(s):  
F. RAHAMAN ◽  
S. CHAKRABORTY ◽  
J. BERA
Keyword(s):  
Cosmological Model ◽  
Exact Solutions ◽  
Lyra Geometry ◽  
Inhomogeneous Cosmological Model ◽  
Normal Gauge ◽  
Lyra’S Geometry

Exact solutions are obtained for an inhomogeneous cosmological model in normal gauge for Lyra's geometry. Some properties of the model have also been discussed.

scholarly journals Scalar field cosmology in Lyra's geometry

2015 ◽  
Vol 3 (2) ◽  
pp. 117 ◽  
Author(s):  
V. K. Shchigolev ◽  
E. A. Semenova
Keyword(s):  
Exact Solution ◽  
Scalar Field ◽  
Generating Function ◽  
Function Method ◽  
Scalar Fields ◽  
First Order ◽  
Homogeneous Cosmological Models ◽  
Different Types ◽  
Lyra’S Geometry ◽  
Scalar Field Cosmology

<p>The new classes of homogeneous cosmological models for the scalar fields are build in the context of Lyra’s geometry. The different types of exact solution for the model are obtained by applying two procedures, viz the generating function method and the first order formalism.</p>

scholarly journals Quadratic integrals of a multi-scalar cosmological model

2020 ◽  
Vol 35 (10) ◽  
pp. 2050068 ◽  
Author(s):  
Sameerah Jamal
Keyword(s):  
Scalar Field ◽  
Cosmological Model ◽  
Conservation Laws ◽  
Analytical Solutions ◽  
Physical System ◽  
Noether Symmetries ◽  
Spatial Curvature ◽  
Special Case ◽  
Friedmann Robertson Walker ◽  
Field Integral

In the context of Friedmann–Robertson–Walker (FRW) spacetime with zero spatial curvature, we consider a multi-scalar tensor cosmology model under the pretext of obtaining quadratic conservation laws. We propose two new interaction potentials of the scalar field. Integral to this task is the existence of dynamical Noether symmetries which are Lie–Bäcklund transformations of the physical system. Finally, analytical solutions of the field are found corresponding to each new model. In one of the models, we find that the scale factor mimics [Formula: see text]-cosmology in a special case.

Sign in / Sign up

Export Citation Format

Share Document