Spanspermia: Does Life Come from Outer Hilbert Space?

Steve Dufourny

SepiaBeetle
Be frank, what is your chosen interpretation of QM? The MWI is not it. It is not me who does not know the fundamentals. It is not a failure if you are not able to develop deep ontological possibilities and extrapolate them with neutrality. Some are good in details, but they are not good for generality and doubt. It is like this. I don t know all me, I recognise it even If I cannot stop to study maths and physics since I was at university , I am 50 years old, I study all days because simply I am passionated and I cannot stop.There I study in details the ZX calculus and diagrams of Penrose. I correlate these works with my theory of spherisation and the spherical quantum volumes.

SepiaBeetle

Steve Dufourny

My interpretation of QM will not change the argument I am making. It is irrelevant, because the ideas I am presenting are grounded in the formalism. You can discuss interpretation until you're blue in the face and you will be no closer to understanding quantum mechanics. You're confusing the more accessible, and much more easily abused dressing of the theory with the theory itself.

Steve Dufourny

SepiaBeetle I fully respect the rigor of formalism, the problem is not there but my point is ontological. Focusing only on formalism risks circular reasoning, we describe what we observe with math and then conclude there is nothing more to discover, I d have liked if some extrapoaltions could have given possibilities beyond the How, I like the why . The problem is there, so we cannot really go farer I think in our discussion, It was a pleasure to discuss even if we disagree, Wish you all the best in this essay contest and in the life, regards

Ulla Mattfolk

The big problem in quantum and in consciousness is the quantum measurement poblem and decoherence. About size or scale we don't know (Susskind, the vienna group). Entanglement is not depending on scale generally. Tunnelling not either. Spin, no..

Why does nobody discuss this? How can we make the theory of decoherence differently, as instance use noise like 'life' does (topological quantum computing)? What about the role of water, can we have quantum in water (plants), or in oil (anasthesia?) +the role of em-force? The quantum theory of today is perhaps not good enough (Penrose and t'Hooft)

Also regarding scale you don't say anything about microtubulis and the measurement in Gran Sasso (Curceanu et co). What do you think about it, are there errors or other more classical interpretations?
Ulla.

SepiaBeetle

Ulla Mattfolk

I'd actually contend the big problem with quantum consciousness is that there is a yawning chasm between the theory it employs and the phenomena it is trying to explain. In that sense it is worse than useless, and I simply do not understand how anyone can take it seriously.

and in fact, to follow up - entanglement and (de)coherence massively depend on scale, particularly in terms of their sensitivity to perturbation.

SepiaBeetle

Steve Dufourny

Okay, if your concern is ontology that's fine, but it's not mine, and it's not the concern of the essay! I don't believe any ontology-led program is an effective way to do physics research, precisely because it necessarily presumes there is a right answer to a question that - if we are really honest - isn't even well posed. So in that regard I have nothing to say - I'm more concerned in statements with predictive power, and which can be falsified through the predictions they make on testable outcomes.

Ulla Mattfolk

SepiaBeetle No, entanglement is non-local and does NOT depend on scale. In quantum computing and teleportation experiments they have successed to send info 1000's of km.

And all those 'unexplained' phenomena I listed should be adressed. It is too easy to just say no, impossible. There is no Life! This is a serious drawback in your essay. Ulla.

Alo98

The essay proposes a critical reflection on the notion of quantum biology, arguing that life, although grounded in chemical processes described by quantum mechanics, does not depend on functional quantum effects on a biological scale. The author demonstrates that, as the size of systems increases, coherence and entanglement are rapidly suppressed by decoherence and laws, making specificities predominantly classical. Frequently cited cases, such as enzymatic tunneling, magnetoreception, and photosynthesis, are reinterpreted as specific to well-explained chemical products without resorting to broad quantum hypotheses. In a provocative and essayistic tone, the text criticizes the inflated and commercialized use of the term “quantum” in contemporary science and proposes, in contrast, that life be understood as essentially algebraic, governed by principles of mathematical representation and organization that, more than the quantum, describe the structure and emergence of living systems.

EmeraldBeetle

SepiaBeetle There was actually one other essay - one of the earliest posted - which largely concerned itself with semantics. I liked it, it had a sensible perspective, but I can't rediscover it in my present browse. Still, you may remember it yourself.

Sounds vaguely familiar and have checked through my notes but I've trudged my way through so many ... evidentially underdetermined essays here that if it was any good it's been drowned out by noise. Also thanks for the 3 recommendations. I've already rated 'Entangled with Life', one of the first essays I read that initially gave me some hope for this competition (I gave it a pass grade), and am checking the other two out.

Also thanks for reading my RSO essay, and no need to lie as us philosophers very much welcome any and all well reasoned critique! Coming from a phenomenological perspective via philosophy of mind, I've worked my way through the various foundational interpretations, and Everett's 'Relative State' interpretation is the only one that makes any real empirical–phenomenal sense to me. Plus I really like the mathematical and logical purity of his starting point, being simply the universal wave function. I would also have thought you'd applaud Carroll's Hilbert space extremism? I do understand however, that 'many worlds' has long been an ontological barrier too high for many!

WRT MWI surviving 'hard contact' in practical applications though, I was of the impression that Zeh/Zurek's decoherence framework (minus foundational QD/envariance) was already a part of the same interpretation-neutral, open system toolbox widely used in practice in quantum information and engineering? Any role for MWI here remains conceptual (Deutsch etc.) as it doesn’t change standard QM’s predictions, so anything operational would be just the same interpretation‑neutral methods. In that sense, I would have thought MWI already survives 'hard contact' with practical applications precisely because it doesn’t ask you practitioners to calculate differently. Everettians leverage the same tools conceptually for quantum foundations, but the practical application is the same either way, isn't it?

But anywho, most of all, thank you for this invigorating interaction! The last FQxI competition in 2020 was actually a lot of fun in the forums here, I got to have interesting discussions with professional thinkers like Marcus Müller, Cristinel Stoica, Alyssa Adams and others. The interactions I've had so far this competition have mostly been with friends or acquaintances of Messrs Dunning and Kruger so when I read your essay (and now comments here) I found it wonderfully refreshing in its professional confirmation of my nonspecialist but growing bias concerning the question of 'quantum biology'!

Your essay is literally the only one I've read so far that comes close to a first prize professional submission, but yes, it's so deflationary (marmite! 🙂 ) to the theme that justice may not prevail.

RoseWren

EmeraldBeetle было ещё одно эссе — одно из самых ранних опубликованных, — которое в основном касалось семантики.

This? https://qspace.fqxi.org/competitions/entry/2365#control_panel

SepiaBeetle

EmeraldBeetle

Thanks again for the kind words. I really wish I had the time to engage with you properly on this many worlds point, but for now I'll just try and drop a provocative idea on your head, on the off chance it's illuminating. Would you believe in many worlds if the wavefunction was simply describing classical physics? That is, no intrinsic uncertainty, no entanglement between observable statistics, but an otherwise identical formalism?

I don't know how strong your mathematical background is, but if you're not afraid of some quite hideous algebra, I'd recommend taking a look at this paper: https://arxiv.org/abs/2302.13208. The question one should be asking themselves throughout is whether it would be a reasonable interpretation of probability to say every time we sample from a distribution, our observed outcome is actually just evidence that we are in an ensemble of all outcomes. Anyway that's about all I can sensibly say without breaking out a fair amount of formal machinery, but the fact one can make a formal correspondence to a classical system - and that this emerges in a singularity-free manner as the limit of commutativity - means that you have to wear classically all the interpretational baggage you lay on the quantum wavefunction. For me that renders MWI - and any non-statistical interpretation of the formalism - completely absurd.

SepiaBeetle

Ulla Mattfolk

Sorry for the confusion Ulla - by scale I mean the number of particles in the system, not the length or time scale!

And as mentioned in the essay, entanglement is non-local but non-signalling. There is no way to transmit information non-locally through entanglement alone. It's a very important fact about causality, and is how I argue the why of entanglement not being a solution to the hard problem of consciousness.

Ulla Mattfolk

SepiaBeetle Vlatko Vedral talks of not particles, but Q-numbers and clusters. Sounds interesting. We are in a backwater now and must find new ways to look.

EmeraldBeetle

SepiaBeetle Would you believe in many worlds if the wavefunction was simply describing classical physics? That is, no intrinsic uncertainty, no entanglement between observable statistics, but an otherwise identical formalism?... the fact one can make a formal correspondence to a classical system - and that this emerges in a singularity-free manner as the limit of commutativity - means that you have to wear classically all the interpretational baggage you lay on the quantum wavefunction. For me that renders MWI - and any non-statistical interpretation of the formalism - completely absurd.

Ah, you're one of those KvN people! Thanks for the refresher, and I know enough linear algebra to barely get me in trouble but it's not the proofs but their philosophical implications that interest me. Also WRT 'belief' in MWI, as a philosopher I don't believe in anything other than what my own empirical–phenomenal experience discloses, and any talk of external physical realities is by definition theoretical-model-speak. As the eminent game theorist Hugh Everett insisted, "any physical theory is a logical construct (model) ... some of whose elements are associated with elements of the perceived world".

But I've never quite understood why reformulating the mathematical formalism of Schrödinger's wave function and then taking the classical limit \hbar \to 0 in order to recover a Hilbert‑space representation of classical dynamics is anything other than a fancy‑dress maths trick. Nor how that trick is ontologically relevant to a quantum worldview.

If KvN could derive genuinely quantum interference phenomena – entanglement, Bell violations or environmental decoherence and pointer states – from the statistical interpretation of the formalism, then that's totally fine by me! We can all just forget about the 'quantum weirdness' that's been spooking people for the last century and reinstate a coherent “belief” in classical realism as the ontological form of the external physical reality. Quantum foundations done and dusted! But you can't, can you? It's an aspiration built on what I call 'classical nostalgia' for those simpler ontology days.

And as for those various 'belief systems' concerning the structure of the external physical reality, doesn't KvN simply presuppose classical phase‑space realism in its 'Hilbertisation' of classical phase space? My own intuition, following Kant, is that spacetime is an emergent perceptual reality of our phenomenal world and that we don't actually need to load that phenomenal spacetime‑grid “interpretational baggage” onto the external reality. That's why I find the simplicity of a universal wave function evolving as a single state vector in an infinite‑dimensional Hilbert space (with its noncommutative observable algebra) a rather intriguing philosophical model for the external reality. And Everett offers a bridge from there to our decohering, quasiclassical, local light‑cone phenomenal experience of our 3+1D phenomenal world.

The simplicity of that Everettian 'external picture' really does fit nicely with my neo-Kantian philosophical 'phenomenal picture', I guess much like your KvN formalism suits your neo-classical spacetime picture. And I can see how the former might appear absurd to you stubborn classicists, but each to their own belief system I say!

Lorraine Ford

EmeraldBeetle
What an unpleasant view to have of yourself and of other people, the view that you yourself are equivalent to a mechanical machine that is machine-interacting with other mechanical machine-equivalents!

SepiaBeetle

EmeraldBeetle

Thanks for the spirited reply. I see your problem perfectly, and you’re right, I’m "one of those KvN people"—at least insofar as the algebraic formalism provides a clear structure, which is the point of my essay! You've identified the crux of my problem with the Many-Worlds Interpretation (MWI) and other non-statistical views, but you've mischaracterized the purpose of taking the classical limit $\hbar \to 0$. It’s not about "classical nostalgia" or a "fancy-dress maths trick." It’s about consistency and interpretational solvency. The central point of demonstrating that you can formulate classical dynamics within an identical Hilbert space structure (the Koopman-von Neumann or KvN formalism) is simple: whatever interpretation you ascribe to the quantum formalism must be compatible with its classical limit.

If your interpretation (like MWI) claims the quantum wavefunction $\Psi$ is an ontological object—the real, evolving state of external reality—and that this reality splits every time a quantum measurement occurs, then that same ontological claim must hold true when $\hbar \to 0$ and the system behaves classically. Call this a principle of interpretational continuity, whatever you like. It's a view that's only recently become available because until recently the problem of the semiclassical limit's singularity was a discontinuity where you couldn't strictly identify one object as the limit of the other. The waveeoperator picture I linked now does that, and so an entirely new line of attack on interpretation becomes available. You are forced to wear the "interpretational baggage" (i.e., splitting worlds) in a purely classical setting as well. It becomes absurd to claim that the ensemble of outcomes when flipping a coin (a perfectly classical, commutative system) requires the existence of multiple, non-interacting realities just because the maths can be formulated that way.

The ability to smoothly recover the commutative classical limit means that you cannot introduce ontological claims about the wavefunction in the quantum regime that become evidently absurd in the classical regime. The classical world is just a special case of the quantum one (the limit of commutativity). If your interpretation requires "quantum weirdness" (like splitting worlds) to stop working precisely when the system looks classical, you are making an arbitrary, non-smooth demand on reality. The formalism itself doesn't demand this singularity; MWI does.

My argument is that a statistical and epistemic interpretation of the wavefunction—one that views it as a mathematical description of knowledge, probabilities, and ensembles, rather than an element of external reality—is a natural container for both quantum and classical dynamics. The distinction between them lies purely in how intrinsic uncertainties are related to the algebra of dynamic observables. It's why classically there's no Heisenberg uncertainty but both x and p have uncertainty relations with their conjugate Fourier representations nevertheless. That's all highly indicative that the way to think about all of these things is that the kind of dynamics you get out depends on the kind of statistics you want to see in your distributions. There is no non-statistical quantum effect. Not one. You cannot predict a quantum jump. That's fine - the physical why of that is not a question we need to answer, we just need to recognise what that does to statistics, expressed via a fundamental commutation relation. The algebraic formalism itself is scale-free and pure, and works beautifully. It's the interpretation of that formalism that must be intellectually honest about what it's describing across all scales, from the smallest quantum system to the largest classical one. It’s not about reinstating classical realism; it's about saying MWI is absurdly non-minimal in its ontological commitment, even classically. You’re welcome to your neo-Kantian phenomenal perspective, but if you want your external reality model (the universal wave function) to be epistemically responsible, it must avoid making the same commitment in a classical world where that commitment is readily dismissed.

EmeraldBeetle

SepiaBeetle If your interpretation (like MWI) claims the quantum wavefunction \Psi is an ontological object—the real, evolving state of external reality—and that this reality splits every time a quantum measurement occurs, then that same ontological claim must hold true when \hbar \to 0 and the system behaves classically.

AFAIU the classical limit for MWI, environmental decoherence suppresses interference, making branching dynamically vacuous and giving an effectively single quasiclassical history, with commutators tending to zero. That’s exactly the point though, in that one of the criticisms of MWI is that it just reproduces classical outcomes in that limit, so you can happily apply a classical, commutative algebra. So where’s the absurdity if the “branches” have effectively 'disappeared'?

Plus, while of course there are “no non‑statistical quantum effects”, those statistics aren’t classical but rather quantum (as in non‑Kolmogorov). And I still think KvN (with its commutative algebra and classical stochastics) runs into Bell/contextuality constraints that your McCaul et al. paper doesn’t appear to even discuss.

So I think KvN obviously works nicely as a reformulation of classical mechanics and looks like it's continually being refined, but (unlike McCaul et al.) you’re overstating its ‘deflation’ of quantum nonclassicality and especially its ‘critical’ relation to MWI. But that’s where the theoretical debate has been stuck for quite some time now, which is why I passed over KvN a while ago on my way to 'mad‑dog' Everettianism 🙂

I'm happy to have Everett and his nonclassical friends proved wrong but will have to wait on the next round of KvN rebuttals (I find Wallace quite readable) to see whether your classical nostalgia for phase space realism has finally won the quantum foundations day. Care to wager?

RustSilverfish

SepiaBeetle I had been drawn to this essay by its (frankly brilliant) title and abstract a couple of times, but must admit that in my first few attempts at reading it through I always bounced off of your 'note on style', which reads to me like a preemptive dulling of your blade lest it cut too deeply. If you want to go in, guns blazing, taking no prisoners, then do it! Don't hedge your bets, don't try to prime your audience into preemptively excusing any stylistic overreaches. If you want to draw blood, you should write to the courage of your own convictions, not flinch away from them at the last second!

Nevertheless, I am in broad sympathy with at least your cautions against exaggerated claims that are good for grabbing headlines and funding, but perhaps don't quite deliver on their promise in the long term. It is always good to erect a bit of a dam against the torrent of hype, and one can't deny that slapping 'quantum' in front of virtually any field of study invites a magnitude of hype hard to explain with classical resources. Hence, I do broadly agree with your call to invite quantum biology to distinguish itself as a distinct field of study, rather than just a distinct means of attracting funding.

Additionally, the argument towards an algebraic formulation of biology is interesting, but unfortunately cut too short to be convincing -- perhaps the essay would have benefitted from less airing of the familiar grievances regarding the publish-or-perish culture of academia in favor of more exploration of this intriguing idea. As it is, it feels somewhat tacked on, more of a teaser than an argument, which ends the essay on a somewhat incomplete note.

Let me now first get a couple of -- ultimately minor -- quibbles out of the way. First, the 'randomness' of quantum theory is, to my mind, far from its most distinguishing feature. After all, it can consistently be formulated in a perfectly deterministic fashion, in either the guise of Many Worlds or Bohmian theories. Furthermore, even intrinsically stochastic theories are by no means necessarily quantum. Also, I'm not sure about the claim that non-commutativity fully explains quantum weirdness. Again there are also theories with non-commutative measurements (Spekkens' toy theory, for one) that fail to reproduce certain features of QM (Bell-nonlocality and contextuality, for example). In the reconstruction of quantum mechanics of Clifton, Bub, and Halvorson, non-commutativity follows from the no-broadcasting axiom, but it needs a further one making unconditionally secure bit commitment impossible to yield entanglement, which, as you say, is 'quintessentially quantum'.

On another minor note, you write that 'The essential problem for almost all scientific inquiry is to find the correct representation'. I don't think this is the case at all. Much progress is made, in fact, by changing representations: changing Hilbert space operators for path integrals or a noncommutative phase space algebra. I don't even think there's a good case that there is a 'right' representation: but different ones may work to our advantage in different settings.

As for your overarching argument, I must confess to always having trouble with such 'a priori' declarations of impossibility. There are many things well-known from theoretical considerations that just ain't so. There clearly is space for quantum effects to be efficacious in the macro-regime: that's after all what people are doing with Bell test experiments and the like. An argument that such effects are irrelevant for biology then can't come solely from the physical side, but needs to take into account the biological contribution, as well: effectively rendering it impossible for biological systems to reach whatever narrow sliver of quantum effectiveness can be ported to the macroscale. Is there a gap between what quantum physics provides and what biology can reach, or do both overlap? I don't think the science on either side of this is advanced enough to settle, and moreover it seems to me that even answering it in the negative, requiring expertise both in biology and quantum theory, could well be called an exercise in quantum biology.

Anyway, I thought this was an intriguing essay and, despite my initial stumbling, well worth reading. I hope it'll do well in the contest!

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