Can time travel be scientifically proven?

I watched a show on a science channel a few months back and their conclusion was what I expected...time travel isn't possible. Scientists have claimed to have sent molecules back and forth in time but have been proven wrong. There is a simple way to look at it. For time travel to be possible, time would have to be like a river. In other words, you'd have to be able to go both up and down stream or forward and back in time. Imagine someone invented a machine to do just that and traveled back in time. Okay, now the hard part, where are they? See for time travel to be possible, the future has to be occurring now too. So where are the time travelers? Of course, there's also the problem of changing history and screwing up the so-called present.

As of today, I think it can't be proven yet. It would be cool but it would be really unnatural and would disrupt the balance of our world. But then who knows? There might really be something that can be done to tap into time and go back and forth at will. In a few thousand years, more theories may be formulated and still, it may still be possible. But for now, it really isn't something we could do. Unless, someone out there came from the future. See 'ya.