Sure, this is certainly true from the perspective of being able to totally predict behavior or the subjective elements of experience. But we're just looking for a broad answer for "what causes consciousness." That is, "what phenomena do I need to observe to make me reasonably confident that a system has subjective experience." There isn't any one mainstream theory for this. Rather, there is a constellation of widely variant theories that focus on anything from "all complex enough computation results in experience," to "certain energy patterns = experience," to panpsychism, to brainwaves, to a quantum level explanations.
What is surprising is that, even if we could resolve individual synapses, we aren't sure this would give us an answer. That is, most theories are such that, even if we magically had that sort of resolution, they couldn't tell us "look for X and X will show you if a thing is conscious or not."
By contrast, even for most theories of quantum foundations, we know what observations would count as supporting of falsifying different theories. If we could actually do Davies 10,000 beam splitter experiment we could confirm if the universe really "computes" or if it actually requires real numbers to describe. We can imagine that, if we could "step back" and see parallel universes, we could confirm MWI. However, it's unclear what view you would need, even of a magic sort, to confirm many theories of consciousness. How can we observe panpsychism? I've heard very mixed things.
That all said, I actually agree with you and T Clark. I think it's too early to begin throwing our hands up on the consciousness question given current technical limits. It's not like we have phase space maps of the brain lol. Nothing close. I merely brought that point up because it is popular and could be a point in CCC's favor.
But anyhow, not to get sidetracked on the consciousness question, which is maybe ancillary...
As far as we know, none of the various interpretations of quantum mechanics can be verified even in principle. They are all equivalent. There is no difference except, perhaps, a metaphysical one.
This is not the case, although it is mostly the case. Some forms of objective collapse theories do make distinct predictions about quantum behavior that differs from other interpretations, meaning they can be tested. Indeed, some versions, those where gravity causes collapse, have been tested (and falsified).
For example,
simple formulations of the Diósi–Penrose model appear tohave been falsified, although the model has been kept alive through modifications (which if we're skeptics I suppose we could liken to epicycles.)
Likewise, pancomputationalist theories can be tested to some degree in theory, if not yet in practice. With enough beam splitters, one can configure an experiment that would require more information than the visible universe appears to be able to store to calculate. If pancomputationalists are correct, the universe is computable and infinite real numbers are not really needed to describe it. This would be a way to test that assumption and it would have ramifications for several interpretations of QM that posit real continua (or at least force them to be reformatted in finitist or intuitionist terms.) Such experiments might also lend credence to the advancement of intuitionist instead of Platonist flavored interpretations of mathematics vis-a-vis physics (a line advanced by Gisin), which would in turn have ramifications for many quantum theories and for arguments for eternalism writ large.
Unverified is not the same thing as unverifiable. If I'm wrong and one interpretation of QM can be verified, then your argument will mean something. Modeling the behavior of matter at the smallest scales as atoms and quarks allows generation of predictions of behavior that can be tested. QM interpretations do not.
As noted above, these interpretations have
already resulted in some experiments, and ideas for experiments that could lend support to them. My point is that such experiments never get thought up if the theory isn't invented first.
Take quarks. Quarks were introduced based on pure theory. The same is true of anti-particles. The experiments that made us confident that these were real entities were only dreamed up because the theory already existed and people were interested in it. Quarks were not initially verifiable or falsifiable and were indeed attacked as pseudoscience on those grounds. But people kept working and now quarks are well-established. We won't get a breakthrough without theorizing.
As I noted, if I'm wrong and the various QM interpretations can be tested, then we can have this discussion. I'm not the only one who thinks that is unlikely. I acknowledge I am far from qualified to render an opinion on this. I'm not a physicist. I'm basing my understanding on reading what other more qualified people have written.
You might be interested in Adam Becker's book "What is Real?" It's a pretty succinct explanation of the history of quantum foundations, although it stops in the 1990s when there is really an explosion in the field and gives "It From Bit," pretty short shrift. It goes into detail about
why most physicists don't and don't need to care about this sort of thing. But for those who work in quantum foundations, attitudes are quite different from the general population of physicists.
Now maybe their arguments are colored by the fact that this is what they do for a living, but they seem to have good arguments about why their work matters and how it can advance physics as a whole. And indeed, a lot of big discoveries
have been made from this sort of work. Tests of Bell's Theorem were called "experimental metaphysics," originally, but they ended up having a large impact. He was on the short list for a Nobel before his untimely death for his work on locality and his work on locality stemmed from his interest and work on foundations.
They are not "a number of theories" they are a number of interpretations of one theory. The reason the Copenhagen Interpretation is in any way canonical is that it's really not an interpretation at all. It just describes how quantum level phenomena behave. Shut up and calculate is not metaphysics. It's anti-metaphysics.
Sort of. It depends on how we define theories, but even if we define theories as "only the formalism," different work in quantum foundations does in fact utilize different formalisms, making them different theories by that definition.
Copenhagen isn't "shut up and calculate." Copenhagen has a metaphysical perspective, it's one that is heavily influenced by logical positivism and Carnap. "Shut up and calculate," is seen as equivalent only because:
1. Copenhagen was the first major interpretation that gained traction.
2. It was dogmatically enforced (see Becker's "What is Real?"), and physicists pressured away from perusing other interpretations.
3. Thus, until recently, it was the "standard interpretation." Shut up and calculate just means you ignore the issue, which means the de facto explanation stays in place.
Bohr's complementarity
is itself a metaphysical claim. It explicitly rules out other metaphysical claims like Pilot Waves (Bohm). If you want an interpretation with no metaphysics, that's Quantum Bayesianism (QBism). There, QM is
only about proper statistical inferences about future observations, nothing more. QBism doesn't rule out Pilot Waves or parallel dimensions because it is totally silent on what exists (in mainstream versions I am aware of).
But Copenhagen also comes in for more criticism than most modern interpretations because it essentially
has been falsified. Copenhagen presupposes two worlds, a quantum world where quantum phenomena happen and a classical world. This made sense back in the 50s, but today we've seen macroscopic drumheads entangled, bacteria entangled, quantum effects underpinning all chemistry, huge clouds of atoms entangled, macromolecules used in double slit type experiments. Advances in our theories like decoherence show that the binary of Copenhagen doesn't make a lot of sense.
That's why you'll often hear modern forms of Copenhagen described as "Neo-Copenhagen." A number of interpretation
do hew quite close to Copenhagen, but they also change it to fit experimental data since the 1950s. For example, Roveli's Relation Quantum Mechanics has been described as essentially "reformed Copenhagen." And indeed, he draws on Mach, a huge inspiration for Copenhagen, quite a bit in his book. Although, IMO, it is different enough to be its own thing.
Most physicists don't have to care about this sort of thing, and so people tend to suppose the Copenhagen is more like QBism, being only about inference, rather than being logical positivists' attempt at an interpretation of QM.
This is a straw dog or straw man or straw something argument. The social and psychological mechanisms of consciousness have been studied for decades, centuries, millennia, with some success. The neurological mechanisms of consciousness have not been because the technology has not been available. Over the past few decades, those technologies have been evolving rapidly. Again, this is an argument that has been gone through many times on the forum without resolution.
See above in my reponse to wonderer. I am actually inclined to agree with you here. I am just noting that this is a commonly expressed position and the CCC might help alleviate it, although IMO it would do so in an unhelpful way, in the same sense that MWI solves FTP in a way that isn't helpful.
I'll admit, I find the claim that FTP isn't a problem more of a head scratcher. We have the Big Bang because a whole bunch of observed characteristics seem incredibly
unlikely. We could have just said "well, in an infinite amount of time very unlikely things will happen so we can leave it at that." But we didn't. We got the Big Bang theory, one among any, and it found a lot of support.
However, we still saw all sorts of things that seemed very unlikely. This led to Cosmic Inflation being posited, a period of rapid inflation prior to the Big Bang. Cosmic Inflation helped explain a lot more observations and is now
the theory in cosmology. But if we had simply said "initial conditions don't need to fit any statistical pattern because they are a sample size of one," we never would have developed the Big Band of Inflation theories.
Now, I can totally see thinking FTP is a bad argument for a creator and bad reason to embrace MWI or CCC, that makes perfect sense to me.
The question I have, then, is what is the problem with the Copenhagen interpretation?
The hard division between the quantum and classical scales is generally considered to be its main problem, but this has been revised over the years. The problem is that the revisions have sort of split into different interpretations, so it's hard to see what "Copenhagen" is today unless we return to the version that had to be revised.
But yeah, big picture there is no problem with it except for the fact that it predicts nothing different than any of the other theories, and so can't mark itself out as superior in that regard. It also doesn't answer the FTP issue in the way MWI can, although I am dubious about that being a point in favor of MWI.