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arXiv · 2402.15339

Characterizations of generalized Robertson-Walker spacetimes concerning gradient solitons

Krishnendu De·Mohammad Nazrul Islam Khan·Uday Chand De
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Abstract

In this article, we examine gradient type Ricci solitons and $(m,\tau)$-quasi Einstein solitons in generalized Robertson-Walker ($GRW$) spacetimes. Besides, we demonstrate that in this scenario the $GRW$ spacetime presents the Robertson-Walker ($RW$) spacetime and the perfect fluid ($PF$) spacetime presents the phantom era. Consequently, we show that if a $GRW$ spacetime permits a gradient $\tau$- Einstein solitons, then it also represents a $PF$ spacetime under certain condition.

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Krishnendu De, Mohammad Nazrul Islam Khan, Uday Chand De. 2024-02-23. Characterizations of generalized Robertson-Walker spacetimes concerning gradient solitons. https://doi.org/10.1016/j.heliyon.2024.e25702

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