NPR: These physicists feel our study of the cosmos has been taken too far from what data can constrain with the extra "hidden" dimensions of string theory and the unobservable other universes of the multiverse. by Adam Frank
'Of course, there are many scientists who continue to see great promise in string theory and the multiverse. But, as Marcelo and I wrote in The New York Times last year, it all adds up to muddied waters and something some researchers see as a "crisis in physics."
'Nothing, not even the laws of physics, live above time. The universe is time-bound and time-saturated. Thus, there is no eternal reality of perfect mathematical form. Even the laws of physics themselves must be subject to change. That is the most radical of Unger and Smolin's radical ideas.
'Developing an account of how the laws of physics change, however, also means understanding how it must all play out as a one-time history. From their perspective, physicists can't imagine the universe as one of a vast "ensemble" of universes where different "structural" options (different laws) can be explored. Instead, the Cosmos happened just once and it led to what we are today.'