Time Travel: Is it possible?

[The Source]

I think time travel is possible, and it could have happend allready. If you think about what 'time travel' is at the core, I believe that someone in the future has allready discovered the concept. Einstein's (sp?) Philadelphia Experiment was rumored to be a test on the theory. If you think about how much progress that could have been done since the 40s, you have to wonder if someone in our own time has allready gone backwards. If the concept has been discovered, I do not believe the general public will ever know.