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arXiv · 2303.12168

Evolution of Generalized Brans-Dicke parameter within a Superbounce scenario

S. K. Tripathy·S. K. Pradhan·B. Barik·Z. Naik·B. Mishra
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Abstract

We have studied a superbounce scenario in a set up of Brans-Dicke (BD) theory. The BD parameter is considered to be time dependent and is assumed to evolve with the Brans-Dicke scalar field. In the superbounce scenario, the model bounces at an epoch corresponding to a Big Crunch provided the ekpyrotic phase continues until that time. Within the given superbounce scenario, we investigate the evolution of the BD parameter for different equations of state. We chose an axially symmetric metric that has an axial symmetry along the x-axis. The metric is assumed to incorporate an anisotropic expansion effect. The effect of asymmetric expansion and the anisotropic parameter on the evolving and the non-evolving part of the BD parameter is investigated.

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S. K. Tripathy, S. K. Pradhan, B. Barik, Z. Naik, B. Mishra. 2023-03-20. Evolution of Generalized Brans-Dicke parameter within a Superbounce scenario. https://doi.org/10.3390/sym15040790

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