Big-bang nucleosynthesis (BBN) theory, together with the precise WMAP cosmic baryon density, makes tight predictions for the abundances of the lightest elements.
Deuterium and 4He measurements agree well with expectations, but 7Li observations lie a factor 3 - 4 below the BBN+WMAP prediction. This 4 - 5 mismatch constitutes the cosmic "lithium problem," with disparate solutions possible. (1) Astrophysical systematics in the observations could exist but are increasingly constrained. (2) Nuclear physics experiments provide a wealth of well-measured cross-section data, but 7Be destruction could be *enhanced by unknown or poorly-measured resonances, * Physics beyond the Standard Model can alter the 7Li abundance, though D and 4He must remain unperturbed; Physics is inventing outlandish theories for this puzzle including decaying Super symmetric particles and time-varying fundamental constants. Why don't they consider LENR??? Because they have a closed mind! http://sait.oat.ts.astro.it/MSAIt780307/PDF/2007MmSAI..78..476G.pdf The screening of lithium reactions are as high as 17.4 MeV. LENR is why there is a "Lithium Problem"
