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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"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:


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.

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

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?

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.

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.

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.

But how do you know that there was or wasn't an interference pattern? Did some conscious being observe the results? Oh, but it was after the fact? The quantum erasure experiment proves that time doesn't matter to wave function collapse. There is nothing more "woo" about consciousness causing the collapse vs a many worlds interpretation or any other interpretation of quantum physics. The "woo" label is personal feelings and not science. It's academic slander.

You have a box with 2 wires coming out of it. The wires are connected to a display in the box. Looking at the display is either 1) a live awake human, or 2) a dead spider. Can you tell which is which, without opening the box? Can you use the fact that the human observing something causes a quantum collapse, and the spider doesn't to distinguish them. Can you build a quantum consciousness detector? No.

Suppose I write a simple computer program that takes in data from a quantum physics experiment, and tells me whether the data as a whole is consistent with quantum physics. I don't know where the photon went on any particular run, all any conscious human sees is a single yes or no. Would you expect the same results. Yes.

I take an emulated human mind, and put the whole thing on an extremely powerful quantum computer. I simulate the mind in a superposition of states. Would you expect the quantum computer to go into a superposition correctly, despite the person being conscious.

Suppose Joe has opinions on the numbers 1 to 1000, he either thinks that they are all good, or all bad, or that some half are good and the other half are bad. If you tell him a number, it will take him 1 minute, to say if its good or bad. It would take a classical computer 501 min worst case to tell if he has the same opinion of all numbers. But a quantum computer can do it in just 2 min. https://en.wikipedia.org/wiki/Deutsch%E2%80%93Jozsa_algorithm

If you disagree with any of these, we have a factual disagreement about an experimental result. If you agree, then "consciousness" seems to be an invisible inaudible dragon to quantum mechanics. I would have to ask how you know that its consciousness that causes collapse, not DNA.

If you take the multiverse explanation there is one possibility. In the multiverse view, the observer also proliferates along with the rest of reality as the present diverges into multiple futures and so the "collapse" is really just a clarification - the observer finding more precisely among possible observers which one they are. If this is the case, consciousness is part of the wave function and thus certain thoughts might influence the future wave function as holding particular thoughts bar certain futures from happening. This already occurs indirectly as the scientist consciously decides to run a slit experiment instead of something else, which has definite impact as thought cascades into action. More directly Universities and research groups are doing studies along these lines with random number generators and consciousness. http://noosphere.princeton.edu/ It is less mysterious as it sounds once you realize consciousness is a derived property of molecular/electro chemical structure or "shape" of the quantum fields and as such part of the quantum waveform.

Schrodinger's equation is absolute and the wave function never collapses. When a measurement is made the particle is actually measured in every location that it mathematically could possibly be in. When a conscious being makes a measurement it is also measuring the particle at every location the particle could mathematically be at simultaneously, but a conscious being can only comprehend the particle in one place at a time as if there were separate universes.

Yes, I do agree with what this articles says. There is no way to link QM an experimental science to the traditional notion of consciousness. In a way, it may also have a clue of their relation to the ultimate question, whether there is any reality beyond what QM finds as on date by it's distinctive scientific method. I am more in an enigma when I think about Einstein's ability or his thought processes as a phenomenal scientist to be to grasp the nature of a reality to the extent to which he did. Similarly, the minds of great mathematicians who sees mathematical truths in and through their minds. It reminds me Hegel who stated that what is real is rational and vice versa.
Ancient Greek philosophers talk about the law of conformity or the like thing knows the like. Lastly, nature, if at all it exists or at least in the ways in which science finds it, it seems that, it inadvertantly or else is somehow seeking to itself with the mechanism of the great scientists' brains. Since brain is physical or corporeal, as a part or an evolute of nature, it's efforts for self-knowledge is a mystery. This is the reformulated view of Dr. S. Radhakrishnan, the Indian philosopher in his book "An Idealist View of Life". Consciousness or mind seems to be always in the background or as it is said to be the brain's functional expression or as an epiphenomenon or as an emergent entity etc by experts in the relevant fields during the relentless endeavours of scientists in attempting to have a scientific decoding of the truth, if any behind what it is. I believe that, if time is real, then, since our very act of thinking scientific or otherwise is always temporal, the eventual knownness of the possible truth in it's entirity will be co-terminus with end of the world as a whole. If time persists in it's relative fashion, and if the cosmic Dynamics has to go on, then, it's temporality may ensure that, for the show to go on, truth on whatever in it's form will forever lie in the ever receding horizon of the knowledge or else.

Right, in all these issues surrounding the concept of consciousness tackled by cognitive & neuropsychological sciences etc while trying to explain away it, & reduce it to some quantifiable physical properties, no matter to what extent they have been done using standard scientific tools, methods & peer group's verifications to conclude in some objective truth claims, what has been missing or taken for granted is that, those scientists themselves can never circumvent or ignore their acts of seeing or observing or carrying out all those theoretical operations which presuppose the subjective phenomenon as the given. This was long realized in India by Sankara in the 8th century when he declared that, what is presupposed by all mental acts (including today's sciences) can never be grasped by those which presuppose it (pure consciousness or cin-maatra). He never claimed that it can be known by the finite human mind & senses etc but, he stated that no human experience can occur without their underlying ground which reveals them.

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".

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.

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.

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.

Donald, I'm interested to hear how you know that consciousness is not fundamental? And how do you know it's the property of brains? I'm inclined to think consciousness is both fundamental and not produced by brains. I'd be interested if you could provide an argument against this position.

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.

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.

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

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

What if... And I'm too lazy right now to cite sources right now (I know, shame)... Assume that consciousness and matter are two sides of the same coin - that consciousness is fundamental to the universe. As we've studied smaller and smaller pieces of matter, down to the subatomic (down to pure math - in which, I'd argue, we are working in the realm of metaphysics), we are now starting to see the fundamental inseparability of consciousness and matter. Where we've grown accustomed to the medium-sized goods of everyday experience, we might imagine, that at this level something akin to quantum decoherence takes place.

And for the woo... Consciousness and QM share a lot of unique properties. Although we are a long way from having such a rigid math to describe the former, there are plenty of instances of consciousness transcending space (nonlocal). Consciousness regularly time travels, consciousness/our perspective certainly changes the way we see the world around us.

Considering the weak anthropic principle, we require QM and QM tells us something about who and what we are. Just as learning about anything in nature is self reflective, QM (because we are looking so small and so removed from our everyday reality) might be offering us a glimpse, conceptually and mathematically, into the code of consciousness, so to speak. Think: Kant and a priori synthetic knowledge. QM is in our foundation, much like Kant argued space and causality are part of our foundation.

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.

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:

[...] 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 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 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.
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:

[...] 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.)

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

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