Kaluza-Klein theory

In physics, Kaluza–Klein theory (or KK theory, for short) is a model that seeks to unify the two fundamental forces of gravitation and electromagnetism. The theory was first published in 1921 and was discovered by the mathematician Theodor Kaluza who extended general relativity to a five-dimensional spacetime. The resulting equations can be separated out into further sets of equations, one of which is equivalent to Einstein field equations, another set equivalent to Maxwell's equations for the electromagnetic field and the final part an extra scalar field now termed the "radion".
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A theory which tries to unify the strong nuclear force, the weak nuclear force, the electromagnetic force and gravity. It does this by postulating that the spacetime continuum consists of over ten dimensions. We only perceive three (up and down, left and right, in and out) because the others are too tightly wound. However, we feel the effects of these other dimensions by perceiving them as the fundamental forces.