Open Inflation Without False Vacua
S. W. Hawking, Neil Turok
Abstract
We show that within the framework of a definite proposal for the initial conditions for the universe, the Hartle-Hawking `no boundary' proposal, open inflation is generic and does not require any special properties of the inflaton potential. In the simplest inflationary models, the semiclassical approximation to the Euclidean path integral and a minimal anthropic condition lead to $Ω_0\approx 0.01$. This number may be increased in models with more fields or extra dimensions.
