There was a recent thread started by a vistor asking about time and tachyons. I've seen threads locked or moved before, but this one is completely gone, and I can't even find posts I made in it. A highschool friend is asking me similar questions via email and I wanted to quote some of the responses from there. I agree that thread was going no where since one poster just kept asking the openning question again and again. But please don't delete threads. There was also input from several people on virtual particles. I'd like to have access to these posts. Anyway, one question that came up in that thread which I am still curious about is: Since tachyons violate causality, would this force everything to always be at equilibrium? (ie. interactions cause entropy to increase (2nd law of thermo dynamics) but if interactions can go back in time, then since entropy can't increase in both directions, it would just be constant? ... so tachyons interacting with matter = heat death of universe at all times?).