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Published on: September 5, 2019
Holographic probabilities in eternal inflation
1Center for Theoretical Physics, Department of Physics, University of California-Berkeley, Berkeley, CA 94720-7300, USA.
Physical Review Letters
|December 13, 2006
Summary
The study proposes a local viewpoint for eternal inflation, resolving ambiguities in vacuum probabilities using a holographic approach. It suggests using local entropy production to predict observer emergence, enabling prior-free cosmological predictions.
Area of Science:
- Cosmology
- Theoretical Physics
- String Theory
Background:
- The global description of eternal inflation faces challenges with ambiguous vacuum probabilities.
- A recently noted paradox arises from large expansion factors or lifetimes in cosmological models.
Purpose of the Study:
- To resolve ambiguities in vacuum probabilities within eternal inflation.
- To propose a novel method for predicting observer emergence in different vacua.
- To establish a prior-free prediction framework for cosmology.
Main Methods:
- Adopting a local point of view, favored by holography, to define a probability measure.
- Analyzing the insensitivity of this measure to large expansion factors and lifetimes.
- Estimating observer probability via local entropy production, bypassing anthropic criteria.
Main Results:
- A simple and unambiguous probability measure for vacua is naturally selected by the local viewpoint.
- The proposed measure resolves a recently identified paradox in eternal inflation.
- Local entropy production provides a quantifiable, prior-free method for observer probability estimation.
Conclusions:
- The local perspective offers a robust solution to the measure problem in eternal inflation.
- Entropy production serves as a viable alternative to anthropic reasoning for observer predictions.
- This approach facilitates making testable, prior-free predictions in cosmology.
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