Please take a look at this new scientist (space) article...

 

http://www.newscientistspace.com/article/mg19025533.900-spotting-the-quantum-tracks-of-gravity-waves.html

 

Their calculations show that as the gravitational force from a passing wave slightly changes the momentum of the entangled particles, it should knock them out of their pristine spin state. In principle, that effect could be detected, but it is so small that no one has found a way to pick it up, explains Yeo. He and his team suggest that the effect could be amplified using a process called "entanglement swapping", which allows pairs of particles that have never been in contact to become entangled. "Spin and momentum become entangled to a higher degree so that changing one produces an even larger change in the other,"[/b'] says quantum physicist Chris Adami at the Jet Propulsion Laboratory in Pasadena, California.

 

More info on this arxiv article...the maths looks rather dense, so not sure if any physics experts can clarify the workings behind this theory ?

 

(http://www.arxiv.org/quant-ph/0605135).

I don't know but I'm gonna go read on the Wigner transform of spin.