Journal of Astrophysics and Astronomy

, Volume 30, Issue 2, pp 119–131

The effect of hypothetical diproton stability on the universe


DOI: 10.1007/s12036-009-0005-x

Cite this article as:
Bradford, R.A.W. J Astrophys Astron (2009) 30: 119. doi:10.1007/s12036-009-0005-x


By calculation of the proton-proton capture cross-section, it is shown that the existence of a bound diproton state would not lead to significant production of diprotons during big bang nucleosynthesis, contrary to popular belief. In typical stellar interiors, the stability of diprotons would lead to a reaction pathway for converting protons to deuterons perhaps ∼1010 times faster than the usual weak capture reaction. This would prevent stars of the familiar hot, dense type from occurring in the universe. However, if diproton stability is achieved by an increase in the low-energy strong coupling, gs, then stars with temperatures and densities sufficiently reduced so as to offset the faster reaction pathway to deuterium will appear to meet elementary stability criteria. The claim that there is a fine-tuned, anthropic upper bound to the strong force which ensures diproton instability therefore appears to be unfounded.

Key words

Big bang nucleosynthesis star formation anthropic cosmology 

Copyright information

© Indian Academy of Sciences 2009

Authors and Affiliations

  1. 1.BennerleyWotton-under-EdgeEngland