Particle 'X' may have snuffed out cosmic lithium

For a little more than a decade, scientists have been struggling to explain why the amount of lithium predicted to have been formed in the early universe is about three times the value actually observed. Now, an international team of researchers believes it may have the answer: a new type of particle, outside of the Standard Model, that would have interacted with protons and neutrons shortly after the Big Bang so as to break up lithium-7.