Spontaneous symmetry breaking vacuum energy in cosmology

The gravitational effect of spontaneous symmetry breaking vacuum energy density is investigated by subtracting the flat space–time contribution from the energy in the curved space–time. We find that the remaining effective energy– momentum tensor is too small to cause the acceleration of the universe, although it satisfies the characteristics of dark energy. However, it could provide a promising explanation to the puzzle of why the gravitational effect produced by the huge symmetry breaking vacuum energy in the electroweak theory has not been observed, as it has a sufficiently small value (smaller than the observed cosmic energy density by a factor of 10³²).