In theoretical physics and quantum physics, a graviphoton or gravivector is a hypothetical particle which emerges as an excitation of the metric tensor (i.e. gravitational field) in spacetime dimensions higher than four, as described in Kaluza–Klein theory.
[1] In gravity theories with extended supersymmetry (extended supergravities), a graviphoton is normally a superpartner of the graviton that behaves like a photon, and is prone to couple with gravitational strength, as was appreciated in the late 1970s.
[2] Unlike the graviton, it may provide a repulsive (as well as an attractive) force, and thus, in some technical sense, a type of anti-gravity.
Under special circumstances, in several natural models, often descending from five-dimensional theories mentioned, it may actually cancel the gravitational attraction in the static limit.
[2] Joël Scherk investigated semirealistic aspects of this phenomenon,[3] stimulating searches[4][5] for physical manifestations of this mechanism.