I don’t know. I think some theories in physics say that time travel might be possible but there’s a huge difference between a theory and actually doing something. If we could, we’d have to make all kinds of difficult decisions about whether we would alter the past – the ethics could be quite interesting.
There is a theory that says if you can travel faster than the speed of light, you could travel in time. But we haven’t found anything that can travel faster than the speed of light (yet). So with the current evidence, I don’t think we can time travel.