| MadSci Network: Physics |
There are many educated scientists who take time travel seriously. The first book that you should read on this subject is "Black Holes and Time Warps: Einstein's Outrageous Legacy" by Kip S. Thorne. The mechanism for time travel, and similar effects is gravitational wormholes, which were invented by Professor Thorne. For more technical information about wormhole physics, click here.
The Second Law of Thermodynamics is not a problem. When one includes gravity in the Hamiltonian, there is no longer a lower bound on the energy. Therefore, the conditions for the validity of the Second Law are not satisfied.
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