2006/11/30 by Michael L. Graesser, Michael P. Salem · 1 citation
Physics and Astronomy · #Anthropic principle #Astrophysics #Classical mechanics #Cosmological constant #Cosmology #Cosmology and Gravitation Theories #Dark Matter and Cosmic Phenomena #Dark energy #Galaxies: Formation, Evolution, Phenomena #Gravitation #Inflation (cosmology) #Metric expansion of space #Physics #Planck #Planck length #Planck mass #Planck scale #Quantum gravity #Quantum mechanics #Theoretical physics #astro-ph #hep-ph #hep-th
paper · pdf · doi:10.1103/physrevd.76.043506
published as Phys.Rev.D76:043506,2007 · 25 pages, 3 figures; v2: corrected minor computational errors in Sect. IV; v3: references added, version accepted by PRD
arxiv created 2007/07/21 · openalex publication_date 2007/08/06 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
It is possible that the scale of gravity, parametrized by the apparent Planck mass, may obtain different values within different universes in an encompassing multiverse. We investigate the range over which the Planck mass may scan while still satisfying anthropic constraints. The window for anthropically allowed values of the Planck mass may have important consequences for landscape predictions. For example, if the likelihood to observe some value of the Planck mass is weighted by the inflationary expansion factors of the universes that contain that value, then it appears extremely unlikely to observe the value of the Planck mass that is measured within our universe. This is another example of the runaway inflation problem discussed in recent literature. We also show that the window for the Planck mass significantly weakens the anthropic constraint on the cosmological constant when both are allowed to vary over a landscape.