> I wrote:
> > OK, I can follow you so far: if you return to the past of
> > yourself, you were always part of that past. However, if
> > we introduce the idea of "Many Worlds", another possibility
> > arises: that we may be able to return to a past exactly
> > similar to our own, but with the addition of ourselves (the
> > time travelers). The only difficulty I can see is that
> > there appears to be no way to get back to the "present" you
> > left.
> Since it can't be tested, how would this be different
> from a disintergration device?
It could still be tested. I don't know enough math to do the estimation, but if you do enough time travel tests, with short duration, the chances would increase that you would get the test device before sending one. I think. :)