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arXiv · 2111.10820

Wormhole inducing exponential expansion in $R^2$ gravity

B Modak·Gargi Biswas
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Abstract

Wormholes are considered both from the Wheeler deWitt equation, as well as from the field equations in the Euclidean background of Roberson Walker mini-superspace in $R^2$ gravity. Quantum wormhole satisfies Hawking Page wormhole boundary condition in the Euclidean background of mini-superspace, however, in the Lorentzian background wave functional turns to the usual oscillatory function. The Euclidean field equations for $\kappa=0, \pm1$ lead to the wormhole configuration; as well as oscillating universe in Euclidean time $\tau$. The oscillating universe is equivalent to expanding universe under analytic continuation $\tau=it$ and asymptotically leads to exponential solution. An Euclidean wormhole in the very early era evolves to an oscillating universe in $\tau$, thereafter crossing deSitter radius transition to an inflationary era is evident at later epoch only for $\kappa=1$.

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B Modak, Gargi Biswas. 2021-11-21. Wormhole inducing exponential expansion in $R^2$ gravity. https://arxiv.org/abs/2111.10820

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