Susskind's Challenge to the Hartle-Hawking No-Boundary Proposal and Possible Resolutions

Abstract

Given the observed cosmic acceleration, Leonard Susskind has presented the following argument against the Hartle-Hawking no-boundary proposal for the quantum state of the universe: It should most likely lead to a nearly empty large de Sitter universe, rather than to early rapid inflation. Even if one adds the condition of observers, they are most likely to form by quantum fluctuations in de Sitter and therefore not see the structure that we observe. Here I present my own amplified version of this argument and consider possible resolutions, one of which seems to imply that inflation expands the universe to be larger than 10^{10^{10^{122}}} Mpc.

24 pages, LaTeX, 8 references added and a distinction between Linde's and Vilenkin's tunneling proposals

References in corpus (3)

• Populating the Landscape: A Top Down Approach
• Probabilities in the landscape: The decay of nearly flat space
• Eternal observers and bubble abundances in the landscape

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• Spacetime Average Density (SAD) Cosmological Measures
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