What is cosmological constant; Lambda?
cosmological constant; Lambda definition and meaning on Science terms:
A constant term (labeled Lambda) which Einstein added to his general theory of relativity in the mistaken belief that the Universe was neither expanding nor contracting. The cosmological constant was found to be unnecessary once observations indicated the Universe was expanding. Had Einstein believed what his equations were telling him, he could have claimed the expansion of the Universe as perhaps the greatest and most convincing prediction of general relativity; he called this the “greatest blunder of my life”.