OFFSET
0,1
COMMENTS
Steven Weinberg suggested that the contribution from Goldstone bosons to the effective number of neutrino species present in the era before recombination would be (4/7)*(43/57)^(4/3).
LINKS
Steven Weinberg, Goldstone bosons as fractional cosmic neutrinos, arXiv:1305.1971 [astro-ph.CO], 2013.
FORMULA
Equals decimal expansion of 172*(43/57)^(1/3)/399.
EXAMPLE
0.3924220641608327323408794203612644413782408855111339...
MATHEMATICA
RealDigits[(4/7)*(43/57)^(4/3), 10, 110][[1]] (* T. D. Noe, Jun 03 2013 *)
PROG
(Sage) numerical_approx((4/7)*(43/57)^(4/3), digits=115) # G. C. Greubel, Mar 19 2022
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Omar E. Pol, May 28 2013
STATUS
approved