Statistically-anisotropic tensor bispectrum from inflation

Abstract We develop a possibility of generating tensor non-Gaussianity in kind anisotropic inflation, where (1) gauge field is kinetically coupled to spectator scalar field. Owing this coupling, the coherent mode electric appears and softly breaks isotropy Universe. compute bispectrum linearly-polarized perturbations sourced by find that it strongly red-tilted has distinctive statistical anisotropies including higher-order multipole moments. Interestingly, bispectra with specific combinations linear polarization modes are dominant, their amplitudes depend on different sets This new type statistically-anisotropic can be potentially testable upcoming cosmic microwave background B-mode experiments.