Quote:
Originally Posted by bill_mchale
Now a bunch of theoretical physicists (probably because they are afraid they might at some point go back in time and become their own grandparents, or other such silliness  ), conjecture that the Universe will have some feedback mechanism that will destroy any actual attempts to travel in time (and therefore to violate causality), but that is all it really is, conjecture since causality is merely assumed to exist and has never been proven. |
I think the power requirement is the simple and elegant feedback mechanism preventing us from journeying back into time.