Cosmological observations have established that our universe has positive cosmological constant. A positive cosmological constant profoundly alters the asymptotic structure of space‐time. In this talk, we discuss the linearized gravitational field produced by compact sources in the background with positive cosmological constant ‐‐ de Sitter space. Using the covariant phase space formalism, we obtain the quadrupole formula in such a setting. We also show that the energy flux of gravitational waves measured at future null infinity is the same as that measured across the cosmological horizon of the compact source. To get an order of estimate we also discuss power radiated by a binary system in de Sitter background.
Jahanur Hoque (Indien): Gravitational waves in deSitter background
