Wave-optics limit of the stochastic gravitational wave background

Understand

The stochastic gravitational wave background (SGWB) is a rich resource of cosmological information, encoded both in its source statistics and anisotropies induced by propagation effects.

• We provide a theoretical description of it, without employing theoretical tools which rely on the geometric optics limit.
• Our formalism is based on the so-called {\it classical matter approximation} and it is able to capture wave-optics effects, such as interference and diffraction.
• We show that the interaction between the gravitational waves and the cosmic structures along the line-of-sight produce observable scalar and vector polarization modes, on top of modulating the tensorial ones.