Temperature Dependence of the Neutron Lifespan
  Current precision big bang nucleosynthesis (BBN) studies motivate us to
revisit the neutron lifespan in the plasma medium of the early universe. The
mechanism we explore is the Fermi-blocking of decay electrons and neutrinos by
plasma. As result, neutrons live longer and we find a significant 6.4\%
modification of neutron abundance in the BBN era arising from in plasma
modification of the neutron lifetime. This effect can influence the final
abundances of the light elements in BBN.
