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The whole point of Einstein's equivalence principle (in all its variations) is that gravity is not a force in the same way that the electromagnetism, or the weak and strong interactions give us forces. The fundamental idea is that we are weightless in free fall local inertial frames (on time like geodesics in curved spacetime without rotation about our centers of mass). Therefore, the force of gravity in the sense of Newton's 17th Century theory is locally eliminated. Therefore, whenever we feel weight we are in a locally accelerating non-inertial frame in curved spacetime. We need to objectively accelerate from some non-gravity force in order to stand still in curved spacetime like on the surface of Earth standing "still" on a scale. It's the electrical force that is providing the acceleration that we feel as weight, that moves the pointer on the scale. This is very counter-intuitive and its implication is lost even on PhD high-energy physicists and string theorists.

For example, when in a textbook you see the classical vacuum static spherically symmetric metric tensor field

gtt = (1 - rs/r)

grr = - (1 - rs/r)^-1


rs ~ total energy causing the 4D spacetime curvature

rs/r < 1

Those tensor components are only a representation relative to a privileged class of locally non-inertial accelerating "static" observers where some non-gravity force is keeping them at fixed r.

By the way r is essentially the square root of the Hawking-Bekenstein-'t Hooft-Susskind maximal thermodynamic hologram entropy/information of the 3D space that a closed 2Dsurface at fixed r surrounds. Any attempt to squeeze more information into that volume will cause a black hole event horizon to develop at that r. Area of the surrounding surface is always the Euclidean 4pir^2.

String theorists like to invoke 6 or seven extra space dimensions, but there is no real evidence for them nor for supersymmetry between fermions and bosons in 3D space. Perhaps the LHC will provide such evidence?  The idea is that timelike geodesics in the larger spacetime unify all the forces. This is a formal extension of Einstein's equivalence principle that would provide a consistent conceptual unification in the sense of the old Kaluza-Klein idea. 

The physics of the 2D event horizon hologram screens both for black holes and for the observer-dependent dark energy cosmology is anyonic with fractional quantum statistics. Somehow these surface anyons make 3D hologram images that would have supersymmetry that is badly broken in our world. No one has shown how this works in detail as yet.