Neither space nor time has any existence outside the system of evolving relationships that comprises the universe. Physicists refer to this feature o… - Lee Smolin

Spacetime... turns out to be discrete, described by a structure called spin foam.

String theory seems to be incompatible with a world in which a cosmological constant has a positive sign, which is what the observations indicate.

In both quantum theory and general relativity, we encounter predictions of physically sensible quantities becoming infinite. This is likely the way that nature punishes impudent theorists who dare to break her unity. ...If infinities are signs of missing unification, a unified theory will have none. It will be what we call a finite theory.