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arXiv · 1204.1521

Fubini instantons in curved space

Bum-Hoon Lee·Wonwoo Lee·Changheon Oh·Daeho Ro·Dong-han Yeom
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Abstract

We study Fubini instantons of a self-gravitating scalar field. The Fubini instanton describes the decay of a vacuum state under tunneling instead of rolling in the presence of a tachyonic potential. The tunneling occurs from the maximum of the potential, which is a vacuum state, to any arbitrary state, belonging to the tunneling without any barrier. We consider two different types of the tachyonic potential. One has only a quartic term. The other has both the quartic and quadratic terms. We show that, there exist several kinds of new O(4)-symmetric Fubini instanton solution, which are possible only if gravity is taken into account. One type of them has the structure with $Z_2$ symmetry. This type of the solution is possible only in the de Sitter background. We discuss on the interpretation of the solutions with $Z_2$ symmetry.

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Bum-Hoon Lee, Wonwoo Lee, Changheon Oh, Daeho Ro, Dong-han Yeom. 2013-06-12. Fubini instantons in curved space. https://doi.org/10.1007/jhep06(2013)003

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