What is the fifth dimension?
In physics, the Fifth dimension is a hypothetical extra dimension beyond the usual three spatial and one time dimensions. Some scientists have speculated that the graviton, a particle thought to carry the force of gravity, may “leak” into the fifth or higher dimensions which would explain how gravity is significantly weaker than the other three fundamental forces. The Kaluza-Klein theory used a fifth dimension to unify gravity with the electromagnetic force, and now is seen as essentially a gauge theory with gauge group the circle group. M-theory suggests that space-time has eleven dimensions, seven of which are “rolled up” to below the sub-atomic level.
