if wormhole exist we have time machines, coz if the 2 ends are moving in a different rate throught time they will be spereted not only in space, but in time 2. if let us say that 1 opening is in a orbit around our sun at a distance of plutos radie. and the other end is close to a neutron star, or moving whit speeds close to light. they will be seperated throught time, and woila, we have a time machine, but we still cant change the past, and if you ask me, relativity and quantum mechanic give as much sense both, sometimes I think relativity givers more