Quantum Mechanics, Nothing to do with Consciousness

post by Donald Hobson (donald-hobson) · 2018-11-26T18:59:19.220Z · score: 10 (9 votes) · LW · GW · 18 comments

Epistemic status: A quick rejection of the quantum consciousness woo. If you have already read the sequences, there's nothing new in here. If your new to the site, or need a single page to point people to, here it is.

Real Quantum mechanics looks like pages of abstract maths, after which you have deduced the results of a physics experiment. Given how hard the maths is, most of the systems that we use quantum mechanics to predict are quite simple. One common experiment is to take a glass tube full of a particular element and run lots of electricity through it. The element will produce coloured light, like sodium producing orange, or neon producing red. So take a prism and split that light to see what colours are being produced. Quantum physisists will do lots of tricky maths about how the electrons move between energy levels to work out what colour different elements will produce.

There have been no quantum mechanics experiments that show consciousness to have any relevance to particle physics. The laws of physics do not say what is or is not conscious, in much the same way that they don't say what is or is not a work of art. Of course, consciousness is a property of human brains, and human brains, like everything else in the universe, are made of electrons and quarks playing by quantum laws. The point is that human brains are not singled out for special treatment, they get the same rules as everything else.

For the writers among you, think of a word processor feature that takes some text, and turns it into ALL CAPS. You can put a great novel into this feature if you want. The point is that the rule its self acts the same way whether or not it's given great literature. You can't use the rule to tell what is great literature, you have to read it and decide yourself. Consciousness, like literature, is a high level view that's hard to pin down precisely, and is largely a matter of how we choose to define it. Quantum mechanics is a simple, mechanistic rule.

Yes I know that some of you are thinking of the double slit experiment. You make a screen with two slits, shine light through and get an interference pattern. Put a detector at one slit, attach a dial to the detector, and have a scientist watching the dial so they can see which slit the photon went through, and the interference pattern disappears. Perhaps, thought some of the early scientists, consciousness causes the quantum wave function to collapse, the universe doesn't like us knowing which slit the photon goes through.

However, lets do a few more experiments. Repeat the previous one, except that the scientist is sleeping in front of the dial. No interference pattern. Turn the dial to face the wall, remove the scientist entirely. Still no interference pattern. Unplug the dial from the detector, so electrical impulses run up the wire and then can't go anywhere. Again, no interference. Whatever is stopping interference patterns, it looks like detectors, not consciousness.

It turns out that any interaction with any other particles, such that the position the other particle ends up in depends on which slit a photon went through, creates entanglement between the photon and the other particle, which destroys interference. And the atoms in the dial, the electrons in the wire, and particles in the detector its self, all have there position depend on where the photon went.

In general, the way to get rid of mysteries is to break them up into smaller mysteries, until your left with loads of tiny mysteries. How life worked used to be one big mystery. But thanks to modern biology, we now have thousands of tiny mysteries about how yeast metabolism can tolerate high levels of alcohol, or how protozoa DNA doesn't get tangled when they replicate. And these are surrounded by large amounts of well understood science. (I'm not a biologist, so these particular things might be solved by now, but you get the Idea) Big mysteries get broken down into a pile of fact, and several smaller ones.

Gluing the "mystery" of quantum mechanics, to the "mystery" of consciousness to make a bigger and more mysterious mystery, would be a mistake even if both of these things were actually mysteries to humanity. Mystery is a blank textbook, not a feature of the world, and in this case, there is a clear picture of quantum mechanics, and a rough sketch of consciousness in the textbooks.


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comment by Dr. Jamchie · 2018-11-28T15:59:57.386Z · score: 9 (4 votes) · LW · GW

"Whatever is stopping interference patterns, it looks like detectors, not consciousness."

That is not the case, as shows delayed quantum eraser experiments. Detector does not stop interference if detected information is deleted:


comment by Elo · 2018-11-26T20:24:05.267Z · score: 9 (4 votes) · LW · GW

This does not pass an idealogical turing test.

I don't see anything here about the science side that the strong proponents of quantum woo would have a problem with. I do see a mischaracterisation of the woo side.

What if there was unsolvable mystery? What would it be like, being you, existing in a universe with unsolvable mystery?

comment by gjm · 2018-11-27T00:00:25.967Z · score: 8 (4 votes) · LW · GW

I think there are two quite separate issues here.

1. Does consciousness play a role in quantum effects? (This idea is pretty clearly in the "woo" category, although there are physicists who seem to take it seriously, and dismissing it as monstrously improbable given that all evidence to date is that the basic principles of the universe operate at a level much lower than that of consciousness seems quite safe.)

2. Do quantum effects play a role in consciousness? (This idea -- which of course needs some elaboration since in some sense everything is quantum effects, deep down -- isn't altogether crazy, though specific theories along these lines have been very handwavy and from what little I know not at all plausible, and personally I would be very surprised if anything of the sort turned out to be right.)

I think OP is entirely concerned with #1, but doesn't make it explicit that #2 is not in view (and e.g. if I am understanding Volodymyr Frolov's comment correctly, #2 is what he's addressing, so at the very least it's possible to think that the article is about #2 as well as #1). Might be worth clarifying.

comment by Volodymyr Frolov (volodymyr-frolov) · 2018-11-27T02:06:44.925Z · score: 1 (1 votes) · LW · GW

That's a valid observation, but my comment is about both of them (should we call them speculations at this point?)

comment by Matthew Barnett (matthew-barnett) · 2018-11-27T10:25:17.588Z · score: 4 (4 votes) · LW · GW

Clearly, thought some idiot, consciousness causes the quantum wave function to collapse, the universe doesn't like us knowing which slit the photon goes through.

In my honest opinion, if I held an opposing view I'd probably shut off mentally at this point and click on another article. Calling John Von Neumann an idiot is always a bit far, but furthermore, I never like it when a critique turns into name calling.

There have been no quantum mechanics experiments that show consciousness to have any relevance to particle physics. The laws of physics do not say what is or is not conscious, in much the same way that they don't say what is or is not a work of art.

I'd say this is far from obvious and would require a bit more philosophical legwork than what was actually presented. Many believe that qualia (individual instances of conscious, or subjective experience) are indivisible atoms of the universe, the ontological fire in our equations. Debunking that is going to take some careful nuance and distinction, rather than dismissal.

comment by cousin_it · 2018-11-27T14:18:04.204Z · score: 4 (2 votes) · LW · GW

I'm not sure von Neumann claimed that consciousness causes collapse. But he did allow that possibility, so you're right that name-calling is unwarranted.

comment by Matthew Barnett (matthew-barnett) · 2018-11-27T23:32:49.429Z · score: 2 (2 votes) · LW · GW

I looked into the claim I made about John Von Neumann and found this interesting physicsforums post on the topic. It looks like from my cursory research that it might be overstating things to say that he claimed consciousness causes collapse.

comment by Volodymyr Frolov (volodymyr-frolov) · 2018-11-26T20:35:29.391Z · score: 2 (2 votes) · LW · GW
Consciousness, like literature, is a high level view that's hard to pin down precisely, and is largely a matter of how we choose to define it.

It is worth noting that Consciousness is a phenomenon which needs an explanation we don't have just yet. But it is still going to be the same phenomenon no matter how we choose to define it; the same way as it doesn't matter how we chose to define wind or lightning for instance, it is still the same feature of nature. The only reasonable definition we can give it right now is to point our finger to it and say: "this is Consciousness".

comment by Donald Hobson (donald-hobson) · 2018-11-27T00:21:11.003Z · score: 1 (1 votes) · LW · GW

Exactly, and we can point our finger and say, "this is literature", we can't write a computer program to detect either. And consciousness, like literature, is a motivated boundary. And almost any dispute about a borderline case becomes a "if a tree falls in a forest ..." argument.

comment by Volodymyr Frolov (volodymyr-frolov) · 2018-11-27T01:44:22.119Z · score: 1 (1 votes) · LW · GW

For the sake of the argument, it doesn't make any difference that we can't write a computer program (BTW, can't we? are you absolutely sure about theoretical impossibility of literature-detecting neural network?) to detect both. For literature we know that it is an emergent phenomenon and we have a solid understanding of what it means for some text to be considered a piece of literature, even though the exact boundaries of literature might be vague.

For literature not only we can point our finger to it but also we can give more precise definition. For consciousness we have no clue what it is. We suspect that consciousness in particular and personal identity in general might be just one type of qualia among many others; but then we have no clue what is qualia.

Consciousness could be an emergent phenomenon (like literature) or fundamental property of our universe. We don't know and there's no good reason to prefer one speculation over the other.

comment by Donald Hobson (donald-hobson) · 2018-11-27T09:48:48.319Z · score: 1 (1 votes) · LW · GW

Im not saying that you can't have a neural network that detects literature. I see no reason for what literature is to be incomputaple, I was aiming more for the idea of a complex vague intuitive boundary. Detect literature is not nearly enough to specify a particular program. As opposed to detect primes.

And no, consciousness is not a fundamental property of the universe.

comment by Volodymyr Frolov (volodymyr-frolov) · 2018-11-27T14:50:20.567Z · score: -2 (3 votes) · LW · GW
And no, consciousness is not a fundamental property of the universe.

Do you have any objective evidence supporting this claim?

If that's just your assumption it would be helpful to clarify it in your essay, as the rest of your arguments follow from it.

comment by rosyatrandom · 2018-11-27T06:36:55.398Z · score: 1 (1 votes) · LW · GW

My quick take on it, via the Weak Anthropic Principle: consciousness is likely to be linked to QM, because we find ourselves in a QM-based world. If it's not *required*, odds are that QM-based realities are amenable
to containing conscious entities.

comment by Gurkenglas · 2018-11-27T12:46:22.849Z · score: 4 (2 votes) · LW · GW

QM-based realities may just be amenable to containing fusion or planets or amino acids.

comment by rosyatrandom · 2018-11-28T03:15:54.696Z · score: 1 (1 votes) · LW · GW

If that sort of order is helpful to developing consciousness somewhere down the line, then that is the link

comment by peter_parker · 2018-12-01T17:53:12.689Z · score: -2 (3 votes) · LW · GW

I think that this post is partly misleading.

We need to distinguish between two things: esoteric influences from consiousness on the behaviour of matter and the problem that the formulation of quantum mechanics how it is actually used in the labs presupposes an observer by having concepts like "measurement" as primitives. The first is clearly woo and I don't know any serious physicist who has defended it. The second is an ongoing matter of scientific investigation.

The Sequences make it seem like the Many Worlds interpretation has solved this problem but that's not true. First, the viability of the technical work of the Many Worlds people is debated and second, the observer-centric Copenhagen interpretation has evolved into more solid versions like Quantum Bayesianism. Besides the interesting name it also has a catchy phrase: "Quantum mechanics is a user's manual."

tl;dr: The position that quantum mechanics involves consiousness because its fundamental objects are not ontic but epistemic still plays an important role.

comment by Rob Bensinger (RobbBB) · 2018-12-01T22:45:15.784Z · score: 5 (3 votes) · LW · GW
The Sequences make it seem like the Many Worlds interpretation has solved this problem but that's not true.

No, Eliezer talks about this at some length. See The Born Probabilities [LW · GW]:

[...] But what does the integral over squared moduli have to do with anything?  On a straight reading of the data, you would always find yourself in both blobs, every time.  How can you find yourself in one blob with greater probability?  What are the Born probabilities, probabilities of?  Here's the map—where's the territory?
I don't know.  It's an open problem.  Try not to go funny in the head [LW · GW] about it.
This problem is even worse than it looks, because the squared-modulus business is the only non-linear rule in all of quantum mechanics.  Everything else—everything else—obeys the linear [LW · GW] rule that the evolution of amplitude distribution A, plus the evolution of the amplitude distribution B, equals the evolution of the amplitude distribution A + B.
When you think about the weather in terms of clouds and flapping butterflies, it may not look linear on that higher level.  But the amplitude distribution for weather (plus the rest of the universe) is linear on the only level that's fundamentally real [LW · GW].
Does this mean that the squared-modulus business must require additional physics beyond the linear laws we know—that it's necessarily futile to try to derive it on any higher level of organization?
But even this doesn't follow. [...]

And Privileging the Hypothesis [LW · GW]:

[...] But, said Scott, we might encounter future evidence in favor of single-world quantum mechanics, and many-worlds still has the open question of the Born probabilities.
This is indeed what I would call the fallacy of privileging the hypothesis. There must be a trillion better ways to answer the Born question without adding a collapse postulate that would be the only non-linear, non-unitary, discontinous, non-differentiable, non-CPT-symmetric, non-local in the configuration space, Liouville’s-Theorem-violating, privileged-space-of-simultaneity-possessing, faster-than-light-influencing, acausal, informally specified law in all of physics. Something that unphysical is not worth saying out loud or even thinking about as a possibility without a rather large weight of evidence—far more than the current grand total of zero.
But because of a historical accident, collapse postulates and single-world quantum mechanics are indeed on everyone’s lips and in everyone’s mind to be thought of, and so the open question of the Born probabilities is offered up (by Scott Aaronson no less!) as evidence that many-worlds can’t yet offer a complete picture of the world. Which is taken to mean that single-world quantum mechanics is still in the running somehow.
In the minds of human beings, if you can get them to think about this particular hypothesis rather than the trillion other possibilities that are no more complicated or unlikely, you really have done a huge chunk of the work of persuasion. Anything thought about is treated as “in the running,” and if other runners seem to fall behind in the race a little, it’s assumed that this runner is edging forward or even entering the lead.
[... O]ur uncertainty about where the Born statistics come from should be uncertainty within the space of quantum theories that are continuous, linear, unitary, slower-than-light, local, causal, naturalistic, et cetera—the usual character of physical law. Some of that uncertainty might slop outside the standard space onto theories that violate one of these standard characteristics. It’s indeed possible that we might have to think outside the box. But single-world theories violate all these characteristics, and there is no reason to privilege that hypothesis.

The main claims Eliezer is criticizing in the QM sequence are that (1) reifying QM's complex amplitudes runs afoul of Ockham's Razor, (2) objective collapse is a plausible explanation for the Born probabilities, (3) QM shows that reality is ineffable, and (4) QM shows that there's no such thing as reality. I don't know what question of fact you think the Quantum Bayesians and Eliezer disagree about, or what novel factual claim QB is making. (I assume we agree 'physical formalisms can be useful tools' and 'we can use probability theory to think about strength of belief' aren't novel claims.)

comment by Alephywr · 2018-11-28T02:42:21.867Z · score: -2 (3 votes) · LW · GW

That's probably true but it still doesn't explain what happened to me in Europe.