Hawking on scientific method, and string theory

2 December 2006

Stephen Hawking on sci­en­tific method, and (obliquely) string theory: “One can not ask whether a theory re­flects reality, just whether it agrees with observations. A good theory is one that ex­plains a wide range of ob­ser­va­tions on the basis of an elegant model, and makes def­i­nite pre­dic­tions for new measurements. … Some very elegant the­o­ries predict extra di­men­sions to space time, above the usual three space and one time dimensions. If the extra di­men­sions were curled up very small we wouldn’t see them. We can’t rule out the­o­ries with extra dimensions, but so far we have no ob­ser­va­tions that require them.”

(I hadn’t re­alised string theory was com­pletely un­sup­ported by evidence. From a BBC Radio 4 interview.)