Exploring the CPT violation and birefringence of gravitational waves with ground- and space-based gravitational-wave interferometers

In the gravitational sector, we study the CPT violation and birefringence of gravitational waves. In presence of the CPT violation, a relative dephasing is generated between two circular polarization states of gravitational waves. This effect induces the birefringence of gravitational waves. We predict the gravitational waveform corrected by it and estimate the expected constraints on it from Advanced Laser Interferometer Gravitational-Wave Observatory, Einstein Telescope and Laser Interferometer Space Antenna.Comment: Preprint, 16 pages, 1 figure, 1 table, 2 appendices. All comments are welcom

Foliations associated to harmonic maps and some complex two ball quotients

The purpose of the article is to study a foliation associated to a lattice-equivariant harmonic map of small rank from a complex ball to another. The result is related to rigidity of some complex ball quotients