Ronald Mallett, a professor of theoretical physics at the University of Connecticut, gave a mind-bending keynote speech on the physics of time travel to an enthralled audience at the Embedded Systems Conference here Tuesday morning, describing how black holes, blue giant stars, and worm holes (tunnels that connect the mouths of black holes) - some of the strangest things in the Universe - illustrate (at least in theory) the potential for time travel some day.

And that day, Mallett claimed, is not so far in the future as one might think.

"Time travel one of mankind's oldest fantasies. But is it really possible? All of us have wondered what's going to happen in the future, and we've contemplated the question, 'What if I could back and change something in my past?" said Mallet. "I am here to tell you we are on the threshold of making time travel a reality, and it's based on real physics."

Author of "Time Traveler: A Scientist's Personal Mission to Make Time Travel a Reality," Mallett explained how the trauma of his father's unexpected death when he was just ten and H.G. Well's book The Time Machine set him on a mission to travel back in time and save his father's life. "Thankfully, I was astute enough not to tell other people about my plan - they were already worried about me," Mallett .

That mission became a lifelong preoccupation, though Mallet says that for many years he used "black holes" as his cover story. "Black holes were considered a crazy idea, but legitimate crazy. That's what helped me survive academia," he said. "It wasn't until I got tenure and was made a full professor that I came out of the time travel closet."

Now other theoretical physicists are looking at time travel, he said, and people are working with him to verify his theories, which are based on Einstein's Theory of Relativity. Mallett did an admirable job explaining the theory, which shows the real possibility of using light to manipulate time, with no math and in less than ten minutes. Possibly it helped that the audience was mainly engineers.

How weird it must have been, he mused, for 19th century scientists to discover through their experiments that the speed of light was constant.

"The only way that speed of light can stay the same is that something else has to be altered. That something else is time - it has to slow down, as experiments have shown," he said. He described a 1971 experiment conducted by the Naval Observatory, in which one atomic clock was kept stationary, and another atomic clock was put on an ordinary passenger jet and flown around world at the speed of sound. The clock on the passenger jet had slowed down--it had lost time exactly way Einstein had predicted.

According to Einstein's theory, gravity will also cause clocks to slow down. Mallett pointed out that everyone in the room was familiar with the phenomenon. He described how early GPS systems did not work properly because engineers failed to take into account that the ground-based units were running noticeably lower than the clocks onboard the satellite. "They actually had to use Einstein's theory to correct the problem."

Because of the strong gravitational force associated with a black hole, Mallett pointed out that it could be used as a kind of natural time machine, though the fact that you'd be ripped apart in the process might not be so pleasant.

Mallett's time machine, based upon a ring laser's properties, may be a more practical approach. His theory of a time machine, he explained, involves creating a circulating beam of light. The energy would produce a gravitational field, which could then be exploited to produce a mechanism for time travel. He's currently seeking funding for further experiments.

He concluded by acknowledging that although he believes we truly are on the threshold of time travel technically, it's important to realize that it's only the moment that counts. "I want you all to enjoy your journey through time," he concluded.