A rift in subspace has appeared, and the characters suspect it might be a temporal portal. Verteron particles are emanating from it. Later, when hell breaks loose and they have to send themselves a message back into the past, a character can use a Diff 4 Reason + Insight (Quantum Mechanics) task to figure out that the particles on this side are entangled with those on the other side, and by generating a phased tachyon resonance pulse from the nagivational deflector they can cause the particles on the other side (and in the past) to vibrate "just so" to transmit the message.
Something like that? :)