Predicting the Cosmological Constant from the CausalEntropic Principle
Abstract
We compute the expected value of the cosmological constant in our universe from the Causal Entropic Principle. Since observers must obey the laws of thermodynamics and causality, it asserts that physical parameters are most likely to be found in the range of values for which the total entropy production within a causally connected region is maximized. Despite the absence of more explicit anthropic criteria, the resulting probability distribution turns out to be in excellent agreement with observation. In particular, we find that dust heated by stars dominates the entropy production, demonstrating the remarkable power of this thermodynamic selection criterion. The alternative approachweighting by the number of ''observers per baryon''is less welldefined, requires problematic assumptions about the nature of observers, and yet prefers values larger than present experimental bounds.
 Authors:
 Publication Date:
 Research Org.:
 Stanford Linear Accelerator Center (SLAC)
 Sponsoring Org.:
 USDOE
 OSTI Identifier:
 899842
 Report Number(s):
 SLACPUB12353
hepth/0702115; TRN: US200709%%500
 DOE Contract Number:
 AC0276SF00515
 Resource Type:
 Technical Report
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; CAUSALITY; COSMOLOGICAL CONSTANT; DISTRIBUTION; DUSTS; ENTROPY; PROBABILITY; PRODUCTION; STARS; THERMODYNAMICS; UNIVERSE; TheoryHEP,HEPPH, HEPTH
Citation Formats
Bousso, Raphael, Harnik, Roni, Kribs, Graham D., and Perez, Gilad. Predicting the Cosmological Constant from the CausalEntropic Principle. United States: N. p., 2007.
Web. doi:10.2172/899842.
Bousso, Raphael, Harnik, Roni, Kribs, Graham D., & Perez, Gilad. Predicting the Cosmological Constant from the CausalEntropic Principle. United States. doi:10.2172/899842.
Bousso, Raphael, Harnik, Roni, Kribs, Graham D., and Perez, Gilad. Tue .
"Predicting the Cosmological Constant from the CausalEntropic Principle". United States.
doi:10.2172/899842. https://www.osti.gov/servlets/purl/899842.
@article{osti_899842,
title = {Predicting the Cosmological Constant from the CausalEntropic Principle},
author = {Bousso, Raphael and Harnik, Roni and Kribs, Graham D. and Perez, Gilad},
abstractNote = {We compute the expected value of the cosmological constant in our universe from the Causal Entropic Principle. Since observers must obey the laws of thermodynamics and causality, it asserts that physical parameters are most likely to be found in the range of values for which the total entropy production within a causally connected region is maximized. Despite the absence of more explicit anthropic criteria, the resulting probability distribution turns out to be in excellent agreement with observation. In particular, we find that dust heated by stars dominates the entropy production, demonstrating the remarkable power of this thermodynamic selection criterion. The alternative approachweighting by the number of ''observers per baryon''is less welldefined, requires problematic assumptions about the nature of observers, and yet prefers values larger than present experimental bounds.},
doi = {10.2172/899842},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Tue Feb 20 00:00:00 EST 2007},
month = {Tue Feb 20 00:00:00 EST 2007}
}

We compute the expected value of the cosmological constant in our universe from the Causal Entropic Principle. Since observers must obey the laws of thermodynamics and causality, the principle asserts that physical parameters are most likely to be found in the range of values for which the total entropy production within a causally connected region is maximized. Despite the absence of more explicit anthropic criteria, the resulting probability distribution turns out to be in excellent agreement with observation. In particular, we find that dust heated by stars dominates the entropy production, demonstrating the remarkable power of this thermodynamic selection criterion.more »

Predicting the cosmological constant from the causal entropic principle
We compute the expected value of the cosmological constant in our universe from the causal entropic principle. Since observers must obey the laws of thermodynamics and causality, the principle asserts that physical parameters are most likely to be found in the range of values for which the total entropy production within a causally connected region is maximized. Despite the absence of more explicit anthropic criteria, the resulting probability distribution turns out to be in excellent agreement with observation. In particular, we find that dust heated by stars dominates the entropy production, demonstrating the remarkable power of this thermodynamic selection criterion.more » 
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