Mathematically?Yes. In practice? Most likely no. Let me explain. When a body moves at the speed of light time doesn't move from it's
perspective.To achive that you should have 0, mass if you don't you will need infinite energy so it's not possible if you have mass. Now theoretically you can't cross the speed of light barrier BUT if you are already across it, technically you don't cross it. If you have read bozonic string theory you already know what I am talking about. If you don't i am talking about the tachyon. Tachyon is a hypothetical particle that moves faster than the speed of light but we haven't found it yet. Now if you move faster than the speed of light you most likely will go back in time. This is really problematic because that means that entropy will decrease (wich is impossible) and of course this will create a lot of paradoxes. In conclusion most likely it's impossible but if you take into perspective the achivements of mankind the last 100 years it's preatty hopefull.
