On 9/09/2015 8:56 am, Stathis Papaioannou wrote:
On 8 September 2015 at 22:11, Bruce Kellett <bhkell...@optusnet.com.au
<mailto:bhkell...@optusnet.com.au>> wrote:
On 8/09/2015 9:14 pm, Stathis Papaioannou wrote:
On 8 September 2015 at 20:48, Bruce Kellett
<bhkell...@optusnet.com.au <mailto:bhkell...@optusnet.com.au>> wrote:
On 8/09/2015 8:40 pm, Stathis Papaioannou wrote:
On 8 September 2015 at 17:39, Bruce Kellett
<bhkell...@optusnet.com.au
<mailto:bhkell...@optusnet.com.au>> wrote:
On 8/09/2015 4:56 pm, Stathis Papaioannou wrote:
I will ask you the same question as I did Brent: do you
conclude from the fact that when you toss a coin it
comes up either as head or tails that the world does
not split into two parallel versions of you, one of
which sees heads and the other tails?
I would conclude that a coin toss does not provide any
evidence for multiple worlds or a split. The only
evidence we have from this data is that the outcome of
the toss is uncertain. There is no evidence there for
any split of anything.
It is not evidence FOR a split but is it evidence AGAINST a
split?
It is evidence that the assumption of a split is not
necessary in order to understand everyday happenings. So, by
the application of Occam's Razor, no split happens.
So you agree that we would still observe the probabilities we do
if we lived in a deterministic world in whaich all possibilities
are realised?
No, because not all possibilities happen in this world. If all
possibilities were realized in this world, then there would be no
uncertainty, no probabilities. Possibility and actuality would be
the same thing. All the horses would win the Melbourne cup; and we
don't live in such a world.
Obviously, not all possibilities happen in this world, but they might
happen in parallel worlds that don't interact with each other. The
argument is that probabilities emerge from this, since you don't know
which world you will find yourself in. You bet on the favourite in the
race because you think you are more likely to end up in a world in
which the favourite wins.
In other words, probabilities can make perfect sense in a single
deterministic world. This was understood a long time ago with the
development of statistical mechanics. The idea that "all possibilities
happen in parallel worlds" does not actually make a lot of sense. There
is no current physical theory that implies this (without the addition of
a lot of unevidenced assumptions). So probabilities do not emerge from
this, they come from quite simple assumptions of randomness and ignorance.
Probability in the MWI of quantum mechanics is problematic. Regardless
of claims to be able to derive the Born Rule in Everettian models, all
attempts fail because they are circular -- they need the Born rule in
order to have non-interacting worlds, so you cannot then use these
independent worlds to derive the Born rule. Gleason's theorem is no help
-- it suffers from all the same problems as the Deutsch-Wallace approach.
Bruce
--
You received this message because you are subscribed to the Google Groups
"Everything List" group.
To unsubscribe from this group and stop receiving emails from it, send an email
to everything-list+unsubscr...@googlegroups.com.
To post to this group, send email to everything-list@googlegroups.com.
Visit this group at http://groups.google.com/group/everything-list.
For more options, visit https://groups.google.com/d/optout.
