Time Travel: A New Hypercomputational Paradigm
Selim G. Akl · 2010
Assuming that all objections to time travel are set aside, it is shown that a computational system with closed timelike curves is a powerful hypercomputational tool. Speci cally, such a system allows us to solve four out of five problems recently advanced as counterexamples to the fundamental principle of universality in computation. The fifth counterexample, however, remains unassailable, indicating that universality in computation cannot be achieved, even with the help of such an extraordinary ally as time travel.