If we could jump into a time machine and meet ourselves at an earlier age, or go forward and see how we look in the future – wow. It’s these possibilities that make time travel so enticing.

When Einstein created his theory of relativity, he laid the foundation for time travel. His calculations determined that time would slow for objects traveling at near light speed. This led many scientists to believe that faster than light speeds could someday allow time travel.

But isn’t light-speed considered the speed limit of the universe? Scientists say yes, but there our ways around this barrier which can be found in black holes, wormholes and cosmic strings.

Black holes form when huge stars collapse into themselves creating gravitational forces equal to faster than light speeds, which conceivably could become a time portal. Wormholes exist throughout space in the form of tiny tunnels that connect now with future and past times, and are considered to have the most potential for time travel. And cosmic strings which line the entire length of the universe generate enormous gravity pull that could someday warp a spaceship through time.

Michio Kaku, Richard Gott, Neil Johnson, Edward Witten, and many other physicists have proposed a variety of ways to build backward and forward time machines. Cal-Tech’s Kip Thorne was the first to publish a scientific paper with the words “time machine” in the title. Thorne worried that reporters might ballyhoo the article causing colleagues to ignore it – but instead, his work brought other scientists out in the open.

World famous physicist Stephen Hawking once opposed the idea of time travel, but has since changed his mind, and now believes time travel is possible.

Now what about the so-called paradox? Say we travel back in time and prevent our parents from getting together. This would prevent us from being born; we would not exist, and our journey in time couldn’t happen.

More here.