Big Bang Nucleosynthesis: The Strong Nuclear Force meets the Weak Anthropic Principle

Abstract

Contrary to a common argument that a small increase in the strength of the strong force would lead to destruction of all hydrogen in the big bang due to binding of the diproton and the dineutron with a catastrophic impact on life as we know it, we show that provided the increase in strong force coupling constant is less than about 50% substantial amounts of hydrogen remain. The reason is that an increase in strong force strength leads to tighter binding of the deuteron, permitting nucleosynthesis to occur earlier in the big bang at higher temperature than in the standard big bang. Photodestruction of the less tightly bound diproton and dineutron delays their production to after the bulk of nucleosynthesis is complete. The decay of the diproton can, however, lead to relatively large abundances of deuterium.

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References in corpus (2)

• Radiative neutron capture on a proton at BBN energies
• Modern theories of low-energy astrophysical reactions

Cited by in corpus (12)

• Life at the Interface of Particle Physics and String Theory
• The Weak Scale from BBN
• The Degree of Fine-Tuning in our Universe -- and Others
• The Entropic Landscape
• $\theta$-dependence of light nuclei and nucleosynthesis
• Binding the Diproton in Stars: Anthropic Limits on the Strength of Gravity
• Multiverse Predictions for Habitability: Element Abundances
• Effects of Bound Diprotons and Enhanced Nuclear Reaction Rates on Stellar Evolution
• Microscopic analysis of quasielastic scattering and breakup reactions of neutron-rich nuclei ${}^{12,14}$Be
• Role of scalar dibaryon and $f_0(500)$ in the isovector channel of low-energy neutron-proton scattering
• Impact of dineutrons on nuclear compositions of a core-collapse supernova
• Experimental Evidence of a Bonded Dineutron Existence