```Ken Wharton wrote:
>Isaac writes:

>>>In C) I did not mean that the universe would then proceed identically
>>>the second time around; whoever travels back in time can survive and
>>>change things around as reality unfolds again.

>>But this is exactly the same case as in B, except that the old universe
>>doesn't exist anymore.

>True again; maybe they're identical.  Or maybe the division between B) and
>C) should have been whether the time travel creates the new universe, or
>whether it was there all along, waiting for you to come into it.

Whatever.  I'm just responding to what you actually did write.

>>>As for the infinite-universe idea, there are some very good philisophical
>>>reasons why it's very improbable.  After all, people we know behave in
>>>predicable ways some of the time.  Why would this be if we're in one of
>>>many universes?  Every past decision made by anyone would be random;
>there
>>>would be no pattern to human behavior.  It's a strong argument against
>>>the many-worlds idea.

>>No it isn't.  Just because decisions are random doesn't mean there's
>>no pattern.  Consider the act of randomly rolling a pair of dice.
>>While the outcome is random, there are certain patterns--the result
>>is always an integer between 2 and 12 (inclusive), sevens are most
>>common, etc...

>Do you really think that every pattern in the world is simply a matter of
>chance?

Our current understanding of physics is _exactly_ this.  However, you
apparently do not understand a significant amount about probability.

>You can do an experiment of asking people how they're doing.  A
>large portion of them will actually respond by saying "fine" or whatever,
>even though the odds of everyone "randomly" behaving this way (and not
>saying random words, clawing your eyeballs out, etc.) are inconceivable.
>Every time you can even somewhat-accurately predict how someone will react
>to a given set of circumstances, you are helping to refute the infinite-
>universe possibility.

Here you demonstrate how little you understand about probability and
what it means to be a random event.

Consider a hypothetical lottery which is randomly determined.  You
buy one of those tickets.  Whether you win or not is random, and
yet the most likely result is that you lose.  Just because something
is random doesn't mean the chances are 50-50.

Similarly, if you go up to John Smith and ask him how he's doing.
Most of the time he'll say "fine".

>I'll leave it there for now.  But don't forget -- you heard it here first.

Actually, Fienman already proposed that antimatter could be interpreted
as normal matter travelling backwards in time.  This doesn't have
anything to do with causality, though.
--
_____     Isaac Kuo kuo@bit.csc.lsu.edu http://www.csc.lsu.edu/~kuo
__|_)o(_|__
/___________\ "Mari-san...  Yokatta...
\=\)-----(/=/  ...Yokatta go-buji de..." - Karigari Hiroshi

```