Generation of gravitational waves by the anisotropic phases in the early Universe

We discuss possible anisotropic and inhomogeneous phases in the early Universe at relatively late epochs corresponding to the temperatures 300 MeV–1 TeV. The anisotropy and inhomogeneity of the stress-energy tensor at the horizon scale gives rise to the generation of a stochastic gravitational wave background. Both the amplitude and spectral energy density of this background are estimated. We also discuss the possibility of the detection this background on working and planned gravitational wave detectors.