Questions concerning GW's are very common on PF, but I think I have a new question on the concept. Maxwell explains that EM waves(photons) propagate in space due to a relationship between the sinusoidal representations of the electric and magnetic fields of the wave. Namely that these two sinusoids are orthogonal and 90 degrees out of phase (if memory serves). Kind of a push-pull relationship. IE, if these components are not present there is no propagation of the EM wave into space. My question is that if EM waves are analogous to to Gravitational Waves, what would be the orthogonal components that would force the GW's to radiate according to Maxwell's explanation of EM waves? Without orthogonal components would not the GW be stationary?