Top 5 SCI-FI TIME TRAVEL METHODS

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Based on Einstein's theory, a black hole is a region of space whose gravitational force is so strong that nothing can escape from it -- even light -- which is why it's black. Credit: NASA

3. Trekking into a Black Hole

Paradoxical time travel isn't a thing of the past for the Star Trek legacy.

The plot of the new film concerns two starships that are sucked into an artificial black hole, sending them 154 years into the past.

While the time-travel method employed in Star Trek IV: The Voyage Home depended on a far too weak gravitational slingshot, many physicists believe that a black hole might indeed provide the necessary portal to the past.

Anything that crosses a black hole's event horizon heads toward an incredibly tiny point of infinitely compressed matter called a singularity. That's also one of the huge problems with the new Star Trek film's plot: What's to keep the two starships from winding up as one with the singularity?

Physicists point to Kerr black holes as a less destructive alternative. These theoretical cosmic phenomena first described by Roy Kerr in the 1960s lack the matter-smashing singularity at the center, potentially making it possible to pass the event horizon and come out the other side -- in another time.

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