In theoretical physics, a graviscalar (also known as a radion) is a hypothetical particle that emerges as an excitation of the metric tensor (i.e. gravitational field) but whose physical properties are virtually indistinguishable from a scalar in four dimensions, as shown in Kaluza–Klein theory. The scalar field
In models with multiple extra dimensions, there exist several such particles.
In theories with extended supersymmetry, a graviscalar is usually a superpartner of the graviton that behaves as a particle with spin 0.
This concept is closely related to that of gauged Higgs models.