Hi.
=20
I just thought up a crazy, crackpot theory for you to munch on, and
it's more of a theoretical exercise than anything useful, really. If,
and IF time travel were possible, AND you could also violate causality
(ie. change history with it), which are probably two really, really
big IFs, then could one create perpetual motion,

Hi.

I just thought up a crazy, crackpot theory for you to munch on, and
it's more of a theoretical exercise than anything useful, really. If,
and IF time travel were possible, AND you could also violate causality
(ie. change history with it), which are probably two really, really
big IFs, then could one create perpetual motion, ie. violate the first
law of thermodynamics? Specifically, you send a particle through your
time machine, so it comes back and meets it's past self. Now we have
two particles. We send those through the machine again and get four.
And so on, and so on. We have a second machine that does the exact
same thing with anti-particles. Once we've built them up to a high
enough amount, we then bring all but one of each together and
annihilate them, releasing lots of energy. The remaining particle/
antiparticle pair is then used to start the cycle again.
Congratulations, infinite energy! Or not? I'm curious, would this
really be so, if our assumptions were true, or is there some subtle,
fundamental flaw? If so (and I wouldn't be surprised if there is one),
what is it? Since the assumptions are quite big, I'd doubt whether or
not you could _really_ get a PM machine this way, but this is not so
much an exercise in designing a device or workable machine as it is
one in speculation.

Congratulations, infinite energy!