Indeed. We pretty much agree then. If you re-read the "real world probability" in the context, I was talking specifically about a belief network. The degree to which a justified belief, in an outcome will occur. All beliefs are by their definitions 'subjective' and occurring in a mind.
Actually my current thinking over the last decade mostly aligns with what could be described as physicalist view of the reality, so even 'subjective' thoughts, ideas, concepts etc exist objectively in a physical sense as well (glia cells, neurons etc). (but that's a whole other topic ;)
I simply worded it 'real word' because I was attempting (perhaps ineloquently I will concede), to differentiate between frequentist and the Bayesian understanding of the term probability, because they differ [1].
Bayesian favors bringing in a priori beliefs into the model whereas a posteriori consideration of a problem, as occurs in frequentist approaches, favor isolation of the model.
>What will actually happen is, the universe splits into many "worlds"
Interesting, you state that so.. assertively :p I'd give the chance of a many worlds interpretation corresponding well with our physical reality, a low probability event, with a pretty high credibility interval ;)
I'd give the chance of a many worlds interpretation corresponding well with our physical reality, a low probability event, with a pretty high credibility interval ;)
There is a theorem that if an experiment and observational apparatus are both quantum mechanical systems, then the many worlds hypothesis describes what happens when that experiment is observed with that apparatus. If quantum mechanics is merely a good approximation of some better theory, then to whatever extent it is a good approximation of the system, the many world hypothesis remains a good description of that interaction.
Therefore your confidence that the many-world's hypothesis is an inaccurate description of what happens when you observe the outcome of a quantum mechanical experiment is an insistence that your brain and body are not well-described by the best theory that physics has for how the world works.
I think most physicists agree that at the bottom, we have a distribution of "complex amplitude"[1] over a "configuration space"[2]. But as you can see from my second link, many (most?) physicists insist that we can derive a "probability" from a complex number. Note that such probability would then be an actual real world probability, where the universe itself is uncertain about what to do. True non-determinism.
It's only natural. At the experimental level, the researcher does observe Born statistics. Same setup, different results, so there is probability in the territory after all.
There's a problem with that however: The equations, which make such wonderfully accurate predictions, (i) are dederministic, and (ii) do not state at any point that the blob of amplitude we don't see disappear in a puff of smoke. They merely say that the blobs eventually stop interacting. The same way that if you launch a photon to outer space, never to meet it again, it won't disappear the instant it reaches the boundary of our observable universe. If you insist on a mono world, you have to assert that the other blob, despite being predicted by those otherwise accurate equations, somehow doesn't exist when you don't see it.
One way to do it is to believe that, contrary to what the equations say, the blob you don't see does disappear in a puff of smoke. Its amplitudes are literally zeroed out behind your back. In hindsight, this one looks nuts to me. I mean, how can we justify distrusting accurate equations in a way that doesn't even make experimental predictions?
Another way is to call the square moduli of those amplitude "probabilities", and pretend that because it's probabilities, the blob you are not in isn't real. But the equations do not make any difference between the two blobs. Then how come the other blob is less real than our own?
To me, those two explanations really feel bizarre. You have to start from a mono world assumption to come up with that. An easy mistake to make, since personal experience is telling us all the time that there is only one world. A bit like a leaf in a binary tree: its ancestors form a line, not a tree. But Kolmogorov complexity says a literal interpretation of the equations (which means many world) is simpler than anything else we currently know about. So to hell with personal experience (which by the way is responsible for much worse whackery than mono world).
Now there is a way out: we can admit that current physics imply many worlds, but insist that real physics probably don't. Current physics are not complete after all. We may have big surprises. This argument is certainly be much saner than the Copenhagen interpretation. So much that it does lower my probability for many worlds somewhat. Just not enough to squash my confidence. :-)
Indeed. We pretty much agree then. If you re-read the "real world probability" in the context, I was talking specifically about a belief network. The degree to which a justified belief, in an outcome will occur. All beliefs are by their definitions 'subjective' and occurring in a mind.
Actually my current thinking over the last decade mostly aligns with what could be described as physicalist view of the reality, so even 'subjective' thoughts, ideas, concepts etc exist objectively in a physical sense as well (glia cells, neurons etc). (but that's a whole other topic ;)
I simply worded it 'real word' because I was attempting (perhaps ineloquently I will concede), to differentiate between frequentist and the Bayesian understanding of the term probability, because they differ [1].
Bayesian favors bringing in a priori beliefs into the model whereas a posteriori consideration of a problem, as occurs in frequentist approaches, favor isolation of the model.
>What will actually happen is, the universe splits into many "worlds"
Interesting, you state that so.. assertively :p I'd give the chance of a many worlds interpretation corresponding well with our physical reality, a low probability event, with a pretty high credibility interval ;)
[1] http://www.experiment-resources.com/bayesian-probability.htm...