Comment by immmmmm

No string theory (10d) or m theory (11d) map to lower dimensions (eg 4d) via (generalisation of) Kaluza Klein compactification. Vector boson (eg maxwell or Yang mills) are internal degree la of freedom-> 6/7d graviton becomes a photon/ gluon.

There’s holography in string theory: AdS/CFT but this rather maps 4d super Yang mills (on the boundary of AdS5) in an AdS5xS5 background: which is one holography correspondence we know works.

Holography is much more common, but we only really understand it on hyperbolic spaces.

Also since it has a theory at strong coupling on one side we cannot really do calculation on that side and verify it.

You can use it tho to make calculations.