Cosmic coincidence or graviton mass?
Abstract
Using the quantum corrected Friedmann equation, obtained from the quantum Raychaudhuri equation, and assuming a small mass of the graviton (but consistent with observations and theory), we propose a resolution of the smallness problem (why is observed vacuum energy so small?) and the coincidence problem (why does it constitute most of the universe, about 70%, in the current epoch?).
 Publication:

International Journal of Modern Physics D
 Pub Date:
 November 2014
 DOI:
 10.1142/S0218271814420176
 arXiv:
 arXiv:1405.4011
 Bibcode:
 2014IJMPD..2342017D
 Keywords:

 Graviton mass;
 dark energy;
 coincidence problem;
 Raychaudhuri equation;
 Bohmian trajectories;
 General Relativity and Quantum Cosmology;
 Astrophysics  Cosmology and Nongalactic Astrophysics;
 High Energy Physics  Theory
 EPrint:
 This essay received an Honorable Mention in the 2014 Gravity Research Foundation Essay Competition. 2 pages, revtex4. arXiv admin note: text overlap with arXiv:1404.3093