I agree with Albert’s critique. I think the gist of it is that Krauss could have meant two things by the term “nothing” in the title of his book (“A Universe from Nothing: Why There is Something Rather Than Nothing“). If by “nothing”, he meant what philosophers (and theologians) have traditionally meant by “nothing”, then he fails to provide an explanation for the why question implied by his subtitle. I take it that what he explains in his book is how vacuum states in relativistic quantum field theory can, under certain initial conditions, evolve into states which describe non-trivial matter/energy content. This is an explanation of how something, maybe a bit more complex, can come from something, maybe a bit less complex. It’s not an explanation of how something can come from nothing in the traditional philosophical sense (although I personally find this traditional philosophical question a bit dull and uninteresting). If by “nothing” Krauss meant “a vacuum state in QFT”, then he does provide an explanation for the why question implied by his subtitle, but I think he’s being disingenuous in portraying this explanation as relevant to the traditional philosophical debate.
Jonathan Bain