Fundamental physics using the temporal gravitational wave background
  We propose a novel probe of fundamental physics that involves the exploration
of temporal correlations between the multi-frequency electromagnetic (EM)
signal and the sub-threshold GW signal or stochastic gravitational wave
background (SGWB) originating from coalescing binaries. This method will be
useful for the detection of EM counterparts associated with the
sub-threshold/SGWB signal. Exploiting the time delay between concomitant
emission of the gravitational wave and EM signals enables inference of the
redshifts of the contributing sources by studying the time delay dilation due
to cosmological expansion, provided that the time-lag between the emission of
gravitational wave signal and the EM signal acts like a standard clock.
Measurement of the inevitable time-domain correlations between different
frequencies of gravitational and EM waves, most notably in gamma-rays, will
test several aspects of fundamental physics and gravitation theory, and enable
a new pathway for current and future gravitational wave telescopes to study the
universal nature of binary compact objects to high redshifts.
