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arXiv · 2111.13913

Cosmic scenario of early Universe in context of Euclidean wormhole in dilatonic Einstein Gauss Bonnet gravity

Abstract

We present some wormhole configurations using analytic and numerical solutions of the Euclidean field equations considering Einstein Gauss Bonnet dilaton coupled interaction in the Robertson Walker metric. Analytic solutions invoking slow-roll type approximation for some potentials yield identical wormholes in the early era. Eventually, in a later era, the universe enters to an expanding era much faster than usual inflation accompanied by oscillations with analytic continuation τ=it. The numerical solutions of wormholes in terms of the scale factor a(τ) are almost identical for some standard potentials of the dilaton field, except for the evolution of potentials. The Hubble parameter and deceleration parameter obtained by curve fit of a(τ) of the numerical solution of wormhole yield an inflationary era away from the throat of the wormhole using τ=it. A sharp decay of the potential is also observed.

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Gargi Biswas, B Modak. 2022-02-15. Cosmic scenario of early Universe in context of Euclidean wormhole in dilatonic Einstein Gauss Bonnet gravity. https://doi.org/10.1142/s0217732322500833

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