Foundations of Physics

, Volume 43, Issue 1, pp 46-53

First online:

On the Foundations of Superstring Theory

  • Gerard ’t HooftAffiliated withInstitute for Theoretical Physics, Utrecht UniversitySpinoza Institute Email author 


Superstring theory is an extension of conventional quantum field theory that allows for stringlike and branelike material objects besides pointlike particles. The basic foundations on which the theory is built are amazingly shaky, and, equally amazingly, it seems to be this lack of solid foundations to which the theory owes its strength. We emphasize that such a situation is legitimate only in the development phases of a new doctrine. Eventually, a more solidly founded structure must be sought.

Although it is advertised as a “candidate theory of quantum gravity”, we claim that string theory may not be exactly that. Rather, just like quantum field theory itself, it is a general mathematical framework for a class of theories. Its major flaw could be that it still embraces a Copenhagen view on the relation between quantum mechanics and reality, while any “theory of everything”, that is, a theory for the entire cosmos, should do better than that.


String theory Black holes Determinism QCD Local conformal symmetry Hidden variables