Good topic for Quanta Magazine, though possibly a bit ambitious? But then it’s Sean Carroll, author of Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime , again (guy gets around), helping us understand his multiverse:
Everett’s brilliant move was simply to say, “And that’s okay” — all we need to do is recognize that each part of the system subsequently evolves separately from all of the others, and therefore qualifies as a separate branch of the wave function, or “world.” The worlds aren’t put in by hand; they were lurking in the quantum formalism all along.
The idea of all those worlds might seem extravagant or distasteful, but those aren’t respectable scientific objections. A more legitimate question is the nature of probability within this approach. In many-worlds, we can know the wave function exactly, and it evolves deterministically. There is nothing unknown or unpredictable. Laplace’s demon could predict the entire future of the universe with perfect confidence. How is probability involved at all?
An answer is provided by the idea of “self-locating,” or “indexical,” uncertainty. Imagine that you are about to measure a quantum system, thus branching the wave function into different worlds (for simplicity, let’s just say there will be two worlds). It doesn’t make sense to ask, “After the measurement, which world will I be on?” There will be two people, one on each branch, both descended from you; neither has a better claim to being “really you” than the other.Sean Carroll, “Where quantum probability comes from” at Quanta
His universe is deterministic, presumably, because everything happens. End of story. Actually, end of all stories.
See also: See also: Cosmologist Sean Carroll: A radical multiverse is the price we pay for unifying physics. Carroll: “The price we pay for such a powerful and simple unification of quantum dynamics is a large number of separate worlds.” Right. And the price you pay for suicide is that nothing you do in this world afterward matters.
Sean Carroll: Physicists don’t even want to understand quantum mechanics
Carroll wants a multiverse out of any new findings, one suspects. One question many might have is, apart from the lack of a multiverse, how bad is the current situation in physics? What, besides that, is going wrong?
At Nature: The “bizarre logic” of the multiverse is explored in a review. Crease writes as if he would very much like to buy into Carroll’s ideas but still thinks that sanity has something to offer. Possibly, many establishment science figures teeter on that brink. In a review of cosmologist Sean Carroll’s new book, Something Deeply Hidden: Quantum Worlds and the Emergence of Spacetime
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16 Replies to “Sean Carroll: Where quantum probability comes from”
Cosmology as Zen.
‘Do you know the sound of one hand clapping?’ is, I believe, a famous Zen satori ?
Hunter S Thompson actually demonstrated one hand clapping and the sound it makes, by boxing a sneering Buddhist teacher’s ear with his cupped hand, thereby damaging the eustachian tube.
I’m not sure, ‘a robust sense of humour’ would best describe Thompson’s gift of satori in this situation.
It’s a koan, not a satori.
Carroll writes in the tradition of Star Trek physicists. In other words, it’s all voodoo superstition. There is a simple reason for quantum probability and it’s not because we were told so by quantum physicists. Nature cannot calculate the exact duration of particle interactions because there is no time dimension. The only recourse, in order to obey conservation laws in the long run, is to use probability. This is why the decay of subatomic particles is probabilistic.
There is no time dimension because it would make motion impossible. This is the reason that spacetime is a block universe in which nothing happens, something that never fails to surprise and annoy scores of relativists.
The Special Theory of Relativity informed physicists that they had a wrong notion of space and time. Space was not absolute, nor was time. They acted ‘relative’ to one another.
The General Theory of Relativity informed physicists that they had a wrong notion of gravitational force: it wasn’t a “force at a distance” that caused gravity, but, rather, space that is curved; that is, non-Euclidean.
It seems to me that if you want to combine quantum mechanics, in particular, quantum field theory, and general relativity, then there is something new to be learned about space. I believe what the MWI of QM given by Everett (and, apparently, so-named by Richard Feynman) is telling us is that space is affected by–a function of, time.
This is because Everett’s point of departure was to contrast the local environment with that of the global environment (the lab room where the QM experiment is conducted versus the quad area outside of the science building). Someone standing in the quad area (global) see’s the the “wave function” of the building as evolving strictly with time–something that he can calculate straightforwardly, while the experimenter in the lab room has set up a “wave function” between an object and a measuring device.
Before the experiment is performed the outcome calculated is only probabalistic, not deterministic like that of the person outside in the quad. What is apparent to me, at least, is that energy density of space is a function of time. But how? Well, that’s the $64,000 question.
What I regret is that scientists eschew a more abstract, conceptual tackling of this quandry in favor of an almost strictly mathematical one. When Einstein spent time thinking about “gedanken” experiments–thought experiments, he revolutionized physics. When he became enamored with the strictly mathematical approach, while laying some of the foundations for the “new” quantum theory, he never again had great influence in his field. I think there’s a lesson to be learned here.
And just like magic, with a little mathematical sleight of hand, Carroll, via updating the wave function to the ‘imaginary observer’ in his imaginary parallel universe, makes the Born Rule falsification of Many Worlds Interpretation (MWI) magically go away.
The irresolvable problem of deriving the “Born rule” (for probability distribution) within the MWI is discussed at the 4:30 minute mark of the following video:
As well, others may not be so enamored with Carroll’s supposed mathematical ‘fix’ of the Born rule in MWI:
Besides that, MWI has been experimentally falsified. Many Worlds (MWI) denies the actuality of wave-function collapse:
And yet, contrary to that axiom within MWI that holds that the wave function does not collapse, the following experiment shows that the wave function does indeed collapse,,
Apparently that experimental refutation of MWI did not make it to whatever parallel universe Carroll may be existing in 🙂
Of supplemental note: MWI, in spite of what Carroll may say, is still just plain insane
i.e. If sanity, and empirical grounding, is to count for anything in science, then MWI should be rejected solely on the basis that it is an unrestained flight of imagination with no empirical support whatsoever..
Carroll might also look up Zeilinger’s recent closing of the free will loop-hole in 2018:
Here is a interesting recent experiment from Anton Zeilinger and company that pushed the “free-will loophole” back to 7.8 billion years ago using quasars to determine measurement settings.
i.e. Contrary to Carroll’s deterministic MWI view of reality, Agent causality is very much alive and well in quantum mechanics
Quantum probability is one of my favorite Big Questions. Who runs the random number generator and where is it located? 🙂 There’s a fair chance this random number generator is part of consciousness. …Or maybe we do indeed live in a fancy simulated environment.
I don’t like the Many Worlds interpretation.
As News pointed out, Carroll’s MWI is deterministic, (as are all ‘realist’ models in quantum mechanics deterministic that neglect the central importance of the Conscious Observer in quantum mechanics).
Atheistic materialism and/or methodological naturalism itself is, by its very nature, completely deterministic. That is to say that free will and/or agent causality is ruled out of bounds in all Naturalistic models before any scientific investigation has even begun.
With no free will, ‘you’ literally become a meat robot with no control over your own thoughts:
Without anyone having any control over their own thoughts, via their free will, reason and rationality itself becomes impossible in science:
As Martin Cothran succinctly puts it, ” The claim that free will is an illusion requires the possibility that minds have the freedom to assent to a logical argument, a freedom denied by the claim itself. It is an assent that must, in order to remain logical and not physiological, presume a perspective outside the physical order.”
Moreover, we no longer have to simply ‘presume a perspective outside the physical order’ in order to believe in free will, (and to preserve reason and rationality within science), but we can also now appeal to quantum mechanics itself. As of 2018, free will has been shown to a integral part of quantum mechanics. Specifically, in 2018 Anton Zeilinger and company have pushed the ‘free will loophole’ back to 7.8 billion years ago, thereby firmly establishing the ‘common sense’ fact that the free will choices of the experimenter in the quantum experiments are truly free and are not determined by any possible causal influences from the past for at least the last 7.8 billion years, and that experimenters themselves are therefore shown to be truly free to choose whatever measurement settings in the experiments that he or she may so desire to choose so as to ‘logically’ probe whatever aspect of reality that he or she may be interested in probing.
Just how counter-intuitive this ‘free will’ aspect of quantum mechanics is to naturalistic presuppositions is touched upon by Anton Zeilinger in the following video. Specifically Zeilinger states, “what we perceive as reality now depends on our earlier decision what to measure. Which is a very, very, deep message about the nature of reality and our part in the whole universe. We are not just passive observers.”
As well, with contextuality we find that, “In the quantum world, the property that you discover through measurement is not the property that the system actually had prior to the measurement process. What you observe necessarily depends on how you carried out the observation”
Thus the reality of free will, (and, by default, the truthfulness of Theism), is now empirically validated by recent advances in quantum mechanics that have now confirmed the validity of free will. A confirmation at the fundamental, quantum, level of reality which provides us with a ‘perspective outside the physical order’ so that we can now firmly ground our ability to reason in a coherent fashion.
i.e. Logic, reason, and thus science itself, is now saved from the catastrophic epistemological failure that is inherent in the determinism of Atheistic Naturalism which denies our free will and thus denies our ability to reason in a coherent fashion in the first place!
Verse and quote:
Of supplemental note:
Also of supplemental note. A lot of the needless confusion surrounding quantum mechanics simply evaporates once we understand how tightly some of our defining attributes of consciousness, (i.e. the experience of ‘the now’ and free will), correlate with the actions we see in quantum mechanics.
I thought it was non-randomness that required a consciousness.
Which is it?
Thank you Hazel. I thought it was another term, and that it would appear in a text, if I Googled ‘satori’. Bizarrely, not so – unless I scanned in too slipshod a manner – which would by no means be rare, admittedly. Thank you for reminding me of the term, though.
‘ Nature cannot calculate the exact duration of particle interactions because there is no time dimension. The only recourse, in order to obey conservation laws in the long run, is to use probability. This is why the decay of subatomic particles is probabilistic.’
Well, how fascinating, Four Faces ! It must be the non-locality thang.
Well, how fascinating, Four Faces ! It must be the non-locality thang.
Yes. Nonlocality is the norm, not the exception. All conservation laws are nonlocal. By the way, there is no action at a distance in the Newtonian sense because there is no distance. Distance (space, volume, area, etc.) is an abstract entity created by the mind. There are only particles, their intrinsic properties (including position) and their interactions. Cheers!
A RNG requires a mind to design and implement. Blind, mindless and purposeless processes do not require a mind.
‘By the way, there is no action at a distance in the Newtonian sense because there is no distance. Distance (space, volume, area, etc.)’ Wow! Of course.
‘There are only particles, their intrinsic properties (including position).’
How ‘position’ ? Within its own margins – so to speak, e.g. upside down, even, somehow, horizontally ?
I didn’t see ‘action at a distance’, as a problem, as I looked at it from a theological perspective ! If God wants two particles to look as if they physically affect each other simultanseously, when miles apart, at his sole discretion, who are we to argue !
Kind of playing games with us and our mighty brains…! As with the fine-tuning of the universe. The very thing, the magnitude of the universe, that convinces the atheists that there must be other inhabited planets, always struck me as a pefect set-up for God to ‘scatter the proud in the imagination of their hearts’, since instead it might well be a way for God to demonstrate how special we are to Him. Of course, magnitude is without meaning to Him, being All in All and non-physical.
As regards the alleged UFOs, there seems to be a welter of at least anecdotal evidence for their existence. However, if true, I believe the ETs are, as has been suggested by Christians, demons, devils.
Sorry, FourFaces, I meant these to be addressed to you. You may not want to comment on them, though. Indeed, they may not even make a lot of sense.
Perhaps the ‘position’ thing indicates the particles create their own reference-frame, according to the configuration they assume.
The author writes, “There is nothing unknown or unpredictable.” But that is not true. Even in the many worlds interpretation, there is still uncertainty in time: when will that energetic particle decay into other particles? We may know its statistical half life, but we cannot predict, and nothing in the physics allows us to calculate when precisely it will decay – hence uncertainty.
The MWI also has a conceptual problem with the multiple, unequal probabilities. Suppose energetic particle X has several possible decay routes, with probabilities 0.60, 0.25, 0.10, 0.05. How does the MWI produce new universes that have different probabilities? Is that 60% of a universe and 5% for another? What does that even mean?