Spacetime Foam + QM+ GR= Strings

Yes only the string theory can unite QM and GR(as best it can) String
theory in the future will be used for TOE It fits well. QM gives us a
point particle perspective,but vibrating strings gives energy to
particles,and that vibrating energy is what we have to visualize. It
gives meaning to the spacetime fabric of inner micro space.(thinking
given a perspective into ultramicroscopic dimensions) String theory in
reality gives the clearest view in this tiny micro realm it is now clear
we will never look into. Best to keep in mind photons don't bounce.
Bert