So there are several theorys as to how you can travel between solar systems and such... 'Faster than light travel', infinite energy is needed to make your "ship" go faster than light because the mass increases madly as you get closer and closer to C. 'Wormholes', huge huge masses are needed to bend space time enough to do whatever is needed to create the wormhole. In short, nothing is quite this dense! But could you not get your spaceship to 0.999C, So its super heavy, then use the ships new mass to create a wormhole and travel somewhere. Obviously it has its flaws, everything wormhole related is entirely theoretical, and the amount of energy required to get any decent sized ship to 0.999C is phenominal, and we must'nt forget the relativistic effects upon the ship in therms of time. However, would it work, in theory ?