time travel cont'd

Here is another article on time travel, and all of this talk about time travel has got me thinking. I don't think it is impossible to travel back to the past, just not likely, but according to my physics classes an object traveling at very high velocity will age more slowly than an object at rest. So if you were to travel to outer space in your spaceship that travels at the speed of light and then return at a later date, you would have aged slower than your fellow friends who remained earth. So is time travel possible?, I for one am just not sure!? And what about "wormholes" that connect parallel universes, can they possibly exist???