[I sent this privately by accident]
James Higgo writes:
> What that postulates is that everything exists, and that means you exist and
> I exist in an infinity of all possible variations. I'm perfectly comfortable
> with this, as I am an MWI-er.
> In this view, the only reason you ever get a physical 'law' is that when the
> random relationships we see as laws break down (which is most of the time),
> we cease to be able to observe it, as the environment then ceases to be
> hospitable to life. The same reson an MWI-er will give for us never seeing a
> vacuum collapse: they occur, but we don't observe those eigenstates in which
> they do, as we aren't alive.
Only if it's a major breakdown. Laws that have small exceptions and
loopholes would still be consistent with our existence.
> The question is, given that all worlds exist, and that the WAP explains why
> we find ourselves in a congenial environment, WHY have I never seen a flying
> rabbit? Why should not the 'laws' break a little bit, to allow non-lethal
> event like that, then repair themselves?
Well, I just asked you the same thing in another message! I don't think
you can explain this without invoking multiple universes.
The normal all-universe explanation is to consider two universes.
One has physical laws as we know them: F=ma (one of Newton's laws), etc.
The other has a law like "F=ma except when Merlin waves his magic wand".
This universe allows for flying rabbits and other magical objects, but
is otherwise basically lawful and people can evolve in it.
Now, obviously the program to compute the second universe is much more
complicated than the program to compute the first one. It has all these
special exceptions in it for when magic is allowed to work, and how.
So it is a bigger program.
We then invoke the principle that large-program universes are inherently
less likely than small-program universes, and presto! we have it more
likely that we live in a universe without flying rabbits, without
magic, etc. That's the general argument we are striving to achieve.
I do think that this argument has some problems, but it is appealing and
if the holes can be filled it seems to offer an answer to the question.
What do you think?