Predicting the cosmological constant with the scale-factor cutoff measure
arXiv:0805.2173 · doi:10.1103/PhysRevD.78.063520
Abstract
It is well known that anthropic selection from a landscape with a flat prior distribution of cosmological constant Lambda gives a reasonable fit to observation. However, a realistic model of the multiverse has a physical volume that diverges with time, and the predicted distribution of Lambda depends on how the spacetime volume is regulated. We study a simple model of the multiverse with probabilities regulated by a scale-factor cutoff, and calculate the resulting distribution, considering both positive and negative values of Lambda. The results are in good agreement with observation. In particular, the scale-factor cutoff strongly suppresses the probability for values of Lambda that are more than about ten times the observed value. We also discuss several qualitative features of the scale-factor cutoff, including aspects of the distributions of the curvature parameter Omega and the primordial density contrast Q.
16 pages, 6 figures, 2 appendices
References in corpus (18)
- Inflationary Cosmology
- Eternal inflation and its implications
- Sinks in the Landscape, Boltzmann Brains, and the Cosmological Constant Problem
- Holographic probabilities in eternal inflation
- Predicting the Cosmological Constant from the Causal Entropic Principle
- Eternal Inflation: The Inside Story
- Towards a gauge invariant volume-weighted probability measure for eternal inflation
- Boltzmann babies in the proper time measure
- A measure of the multiverse
- Predictions in eternal inflation
- Geodesic measures of the landscape
- Testing anthropic predictions for Lambda and the CMB temperature
- Volume Weighted Measures of Eternal Inflation in the Bousso-Polchinski Landscape
- Measures on transitions for cosmology from eternal inflation
- The scale of gravity and the cosmological constant within a landscape
- Predictions of the causal entropic principle for environmental conditions of the universe
- An Observational Test for the Anthropic Origin of the Cosmological Constant
- Probabilities in the Arkani-Hamed-Dimopolous-Kachru landscape
Cited by in corpus (20)
- Properties of the scale factor measure
- Holographic Multiverse
- Multiverse Understanding of Cosmological Coincidences
- Complementarity in the Multiverse
- Surviving the crash: assessing the aftermath of cosmic bubble collisions
- Stationary Measure in the Multiverse
- The Born Rule Dies
- Eternal inflation predicts that time will end
- Cosmological Measures without Volume Weighting
- On the Unlikeliness of Multi-Field Inflation: Bounded Random Potentials and our Vacuum
- Star Formation in the Multiverse
- Consciousness and the Quantum
- Reheating-volume measure for random-walk inflation
- Eternal Inflation, Global Time Cutoff Measures, and a Probability Paradox
- Reheating-volume measure in the landscape
- Agnesi Weighting for the Measure Problem of Cosmology
- Possible Anthropic Support for a Decaying Universe: A Cosmic Doomsday Argument
- Multiverse rate equation including bubble collisions
- Preliminary Inconclusive Hint of Evidence Against Optimal Fine Tuning of the Cosmological Constant for Maximizing the Fraction of Baryons Becoming Life
- Do Our Observations Depend upon the Quantum State of the Universe?