What is MWI?

If you want to read this you'll have to read my most recent reply to
Brett first.

If MWI is the integration of two knowledge sets, one being say "QM
strangeness" then to understand what MWI is we'd need to be really clear
what the other knowledge set is.

That other knowledge is actually a really quite sophisticed structure
featuring multiple assumptions, most of which so far as I know have been
allowed to remain implicit.

One way to look at the structure would be to start with the concept of
Realism. Starting here we begin where the assumptions are at their most
explicit so they'll be most familiar to you.

Realism becomes 'local realism' which you'll know more about than I do.
But what is important is the implicit assumption that follows on from
whatever that is: that whatever the answer will be (i.e. the new
knowledge that becomes MWI) everything important about that assumption
'local realism' is fixed. Meaning, by implication, what we think about
*that* is correct. And the knock-on implication from that is that
whatever the answer will be (i.e. MWI) there will be no knowledge about
*that*. There could be new explanations concerning how local realism
exists in the Multiverse, but that all comes out of a process of
reasoning that fixes local realism in from the start.

Another big assumption is 'determinism'. So again, we hold that concept
as a constant.

Another big assumption is that 'QM strangeness' does not need to be
explained in terms of, say, the Big Bang.

In other words, we've created a structure of assumptions, which amount
to holding a variety of variables constant. And then what we are doing
is bringing it all together in the biggest top most assumption that QM
Strangess is explained in terms of that other knowledge set with all
those variables held constant.

So hence. MWI can be seen as the answer to the question: What would it
take for those [concepts we've held constant] and QM strangeness to be
explained in terms of eachother, i.e. consistent, and part of the same
thing.

Ergo: MWI is what it would take.

So....it's really important to see that MWI is not 'incontrovertible' as
the implication of QM strangeness. Nothing is ever a clean explanation
of just one thing.

And the big problem with MWI is that that other knowledge set has not
been very well worked through. There's some assumptions in there, but
the consequences of those assumptions, and all the play-offs they
entail, are not well understood. So far as I have been able to see.