Holography is the physical boundary effects of Anti-de Sitter (AdS) spacetime of negative curvature spacetime in 5 dimensions threaded by a 5-dimensional hypersphere whose coordinates are hidden on the Anti-de Sitter spacetime via a sphere radius R, with a weak gravity theory acting classically on objects within the full spacetime, being "holographic" to a different space on the conformal z-boundary of the AdS spacetime at some energy realization of the full holographic space being the physics of a quantum field theory on the boundary which couples conformally by strong interactions where . The "holography" is so called because extra information is imparted on the flat boundary surface, whose perspective depends on the energy scale of the boundary cut.
Holography is a example of a weak-strong duality because the weak gravity theory is corresponding with the strong gluon-like conformal field theory at the z-boundary. The gravity-side of the correspondence is a super gravity theory with totally antisymmetric contributions to the field metric, with the dilaton dictating the conformal field strength. Other fluxes must also be present to warp the spacetime necessarily, with the presence of string theoretic Dp-branes, which are boundaries of string end points after canonical quantization of the Polyakov string action, which is itself thought to be the Nambu-Goto string action of trivial strings. The Dp-brane extended objects carry flux flow lines like ordinary charges do, but are of extra size since classical electric flux is .
Holography is not proved, or physical reality because string interactions are have not verified yet amongst its theoretical problems. If physical reality is holographic, then gravity of electric charges would extend to extra dimensions on small string spheres of radius .