Can Bose-Einstein Condensates Enhance Radioactive Decay?

This Letter lays out the principles of how Bose-Einstein condensates can modify radioactive decay. We highlight the challenges of many modes and short coherence times due to the ≈MeV energies of the emitted radiation. Recent proposals for gamma-ray and neutrino lasers claim that using a Bose-Einstein condensate as a source would solve these issues. We show that this is not the case, and the proposed experiments would have a gain of only 10^{-16} or smaller. We also analyze proposals for gamma-ray lasers based on stimulated annihilation of positronium Bose-Einstein condensates.