In this article the wormhole is suggested as a possible time travel device. The only problems suggested being that exotic matter would be required, or it might necessarily self destruct re the laws of physics. i.e be practically impossible.
but unless it is proven that there is indeed a past and/or future then perhaps Relatvity just shows how matter might be warped, stretched, and dilated in its rates of change - but not over a thing called time.
If this is the case then the worm hole 'billiard ball' paradox (for example) can be explained 'timelessly', thus...
Time travel, Worm hole, billiard ball' paradox, Timelessly. (re Paul Davies- New scientist article)