On 2/10/2025 4:09 AM, Quentin Anciaux wrote:
Bruce,
Your argument assumes that all measurement sequences are equally
likely, which is false in MWI. The issue is not about which sequences
exist (they all do) but about how measure is distributed among them.
The Born rule does not emerge from simple branch counting—it emerges
from the relative measure assigned to each branch.
You claim that in large N trials, most sequences will have an equal
number of zeros and ones, implying that the estimated probability will
tend toward 0.5. But this ignores that the wavefunction does not
generate sequences with uniform measure. The amplitude of each
sequence is determined by the product of individual amplitudes along
the sequence, and when you apply the Born rule iteratively,
high-measure sequences dominate the observer’s experience.
But there is no amplitude in the result. The amplitudes are predicted
values. There is not process whereby your measurement is UP and there's
a 0.3 probability tag attached to it. It's just UP, and ex hypothesi
there's another branch where it's just DWN.
Your mistake is treating measurement as though every sequence has
equal likelihood, which contradicts the actual evolution of the
wavefunction. Yes, there are 2^N branches, but those branches do not
carry equal measure.
The point is they have no way to carry any measure at all. That's
something in the prediction which empirically is satisfied by there
being unequal numbers to UP and DWN...NOT by some "weight" they carry.
But the UPs and DWNs are necessarily equal in MWI because everything
possible happens. The distribution is always binomial with p=0.5.
The vast majority of measure is concentrated in the sequences that
match the Born distribution, meaning that nearly all observers find
themselves in worlds where outcomes obey the expected frequencies.
This is not speculation; it follows directly from the structure of the
wavefunction. The weight of a branch is not just a number—it
represents the relative frequency with which observers find themselves
in different sequences. The fact that a branch exists does not mean it
has equal relevance to an observer's experience.
Your logic would apply if MWI simply stated that all sequences exist
and are equally likely. But that is not what MWI says. It says that
the measure of a branch determines the number of observer instances
that experience that branch. The overwhelming majority of those
instances will observe the Born rule, not because of "branch
counting," but because high-measure sequences contain exponentially
more copies of any given observer.
If your argument were correct, QM would be falsified every time we ran
an experiment, because we would never observe Born-rule statistics.
No it is MWI that is falsified because if MWI is applied consistently,
without sneaking in "weights" the distribution would always be binomial
with p=0.5. If you can't understand that, then you don't understand
your own argument.
Brent
--
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 view this discussion visit
https://groups.google.com/d/msgid/everything-list/81e9ee44-cb02-4e8e-8cfe-6490c7e2e9ab%40gmail.com.
