# Fuzzy Euclidean wormholes in the inflationary universe

## TL;DR

This paper explores complex Euclidean wormholes in the inflationary universe, showing they are probabilistically favored over compact instantons under certain conditions, which could impact quantum gravity theories.

## Contribution

It demonstrates that Euclidean wormholes can satisfy classicality conditions in Starobinsky inflation and are more probable than instantons for sufficient e-foldings.

## Key findings

- Wormholes satisfy classicality near the hilltop of the inflaton potential.
- Wormholes are more probable than Hartle-Hawking instantons for inflation exceeding 50 e-foldings.
- Results depend on the Euclidean path integral as the quantum gravity framework.

## Abstract

In this paper, we investigate complex-valued Euclidean wormholes in the Starobinsky inflation. Due to the properties of the concave inflaton potential, the classicality condition at both ends of the wormhole can be satisfied, as long as the initial condition of the inflaton field is such that it is located sufficiently close to the hilltop. We compare the probabilities of classicalized wormholes with the Hartle-Hawking compact instantons and conclude that the Euclidean wormholes are probabilistically preferred than compact instantons, if the inflation lasts more than 50 e-foldings. Our result assumes that the Euclidean path integral is the correct effective description of quantum gravity. This opens a new window for various future investigations that can be either confirmed or refuted by future experiments.