Demolishing prejudices to get to the foundations by Flavio Del Santo and Chiara Cardelli

Flavio and Chiara,

I saw you had some critical comments but you are still doing very well on the leader board so it must have been healthy criticism. I will offer some criticism in the same spirit.

You say that "... the reductionist program has failed even within physics alone, not

having so far being capable to unify the fundamental forces ..." This seems a little harsh. Reductionism and unification has been incredibly successful in physics from the time of Newton until the development of the standard model. There is still some work to unify gravity but to say the whole process has failed for this reason seems to be stretching a point.

You suggest that gravity could have an emergent origin. Weak emergence is part and parcel of reductionism so are you talking about strong emergence? I am skeptical of strong emergence because I don't see how something can emerge if it can not be derived in principle. I think the idea is inspired by the case of consciousness but that is a very special case open to further debate.

I do agree with your message about prejudices. Physicists have been carried away with the successful derivation of everything up to nuclear physics and chemistry from the standard model without the need for any further information to be added. This has given them an expectation that a unified theory including gravity will also allow everything to be derived without further information, at least in principle. On the other hand their recent work is leading to the conclusion that the vacuum is not a unique solution of quantum gravity and quite a lot of information needs to be input to select the correct vacuum. Theorists have responded by saying that this can't be right. They have forgotten that most science from biology upwards requires some extra information about the environment and cannot be derived uniquely from the underlying physics.

You say a lot about falsification. You are certainly a card carrying member of the popperazzi! My only objection here is that the scientific method is merely epistemological. It is just a human construct that we use as a good practice guide for how to do physics. It can't tell us anything about whether a given theory is true of false. Do you agree and how then can it be part of what is fundamental?

I am sure you will have some insightful answers to these questions. Than you for a great essay.

Flavio & Chiara,

This is an excellent essay. You write clearly and use appropriate supporting quotations. Empirical falsification is the very backbone of science and you show how to combine it with philosophy to produce testable questions. The bit about amino acids at the end was a nice touch.

Best Regards and Good Luck,

Gary Simpson

Hello Flavio and Chiara,

I appreciate that your perceptions regarding what qualifies an entity to bear recognition as being 'fundamental' significantly departs from 'commonly accepted views'.

What is surprising to me is that many more thoughtful people don't accept a broader span of possibilities than the 'bottom-up construction or top-down reduction of fundamental entities'.

The reason, I suggest, is that other questions require to be asked and answered prior to engaging in the search for any fundamental unit. One cannot reasonably expect to define what constitutes a fundamental principle or part until one has clearly identified a context within which one can then proceed with the search.

Understanding this contingent requirement necessarily admits the prospect of there being as many 'fundamentals' as there are contexts within which one can proceed.

Physics is a very broad subject, some may say an all-inclusive subject, but how physics relates to the mind, to memory, to ideas, to beliefs, to judgements, to decisions, to time and space, to God, etc., to mention just a few subjects, is not very clear. In the absence of clarity I prefer to step further back to embrace all-there-is, the physical and the abstract, in search of what is the most fundamental prerequisite to enable all-there-is, regardless of form, to be.

The FQXi question What is "Fundamental?" invites a singular response; otherwise the question would be framed: What are "Fundamental?" Thus I am led to my singular fundamental conclusion: 'Existence' is the prerequisite for all else.

Good luck. You are well on your way to happy days!

Gary.

Dear Flavio and Chiara,

Much enjoyed reading your essay, seemed very professional, organized, and informative.

My sense in the first section is that you don't give balance to reductionism and emergence, seem to rule out the possibility that with a satisfactory QM one might arrive at wavefunctions who interactions yield calculable emergence at larger scales. Given the detailed examples of the unsatisfactory state of fundamental physics models that you present at the bottom of the first page, it would be surprising to find models of quantitative emergence already in hand. However it seems a bit hasty to close one's mind so tightly to the possibility as you seem to do for the purposes of your argument.

Very much agree with this statement:

"It thus appears quite unsatisfactory to address foundations of natural science from the perspective of something that has hardly any empirical content."

Well put, thank you for that.

There would seem to be a theoretical minimum for the philosopher/physicist, the requirement being a profound basic understanding of the wavefunction. The proliferation of quantum interpretations speaks to its absence in the community.

Appreciate your definition of that which does not meet the requirements of scientific method:

"Philosophical propositions could be defined as those which are not observationally or experimentally falsifiable at the given moment of the development of human knowledge."

It seems important to be more specific when exploring the fundamental, to address the distinction between quantum and classical when talking about observations. The 'single measurement observable' is the essential concept. Wavefunction collapse yields a lump of energy. One gains the amplitude and loses the phase. Phase is not a single measurement in QM.

The "What is Fundamental" section seems to say nothing about what is fundamental, but rather only dances around what is not.

What you call 'philosophical prejudices' goes deeper that just western philosophy, is best understood in terms of the steps to consciousness outlined in Buddhist philosophy - form (internal or external), emotional tone, perception, volitional formations, and consciousness. The first thing any new idea encounters is emotional tone. Philosophy is up there around volitional formations and consciousness. Most of us are afraid of new ideas in areas where we have attachment, in our professional identities. Despite our protestations to the contrary, we who have professional scientific and/or philosophical identities, the makers and breakers, are all nice and comfortable here in this community, food to eat and a safe place to sleep, lots of good old boys and girls to pat us on the back, no paradigm shifts here please.

Do either of you have thoughts on Hameroff/Penrose microtubules? Will adequate wavefunction models ever exist to describe their functioning? Will this be required to establish a connection between physics and consciousness that satisfies your methodology?

all in all, to describe my sense of your essay i go back to your earlier quote:

"It thus appears quite unsatisfactory to address foundations of natural science from the perspective of something that has hardly any empirical content."

It seems not easy to find empirical content in your essay.

apologies for the anonymous tag on the previous post. Thought I was logged in while commenting.

apologies for the anonymous tag on the previous post. Thought I was logged in while commenting.

Dear Flavio,

Thank you for the courtesy of your reply. My apologies for not being able to communicate my understanding clearly to you. Given that it arises from the mind of and old man, possibilities exist beyond nuance of a young horizon.

Your main theses are imo as you say, childish simple. They have been in my understanding for the greater portion of my life. My sense is that your essay addresses not what is requested by the organizers regarding fundamental in the physical world, but rather a commonly understood procedure for approaching the problem. It says little or nothing about the fundamental itself.

There is weakness in your physics as well, for instance in treatment of non-local entanglement. Inverse square potentials are odd beasts, poorly understood and very important. They correspond to the forces which can do no work, due to the fact that the resulting motion is perpendicular to the direction of the force. They communicate no energy/information. However that can communicate phase, not a single measurement observable. They are your non-local potentials - centrifugal, Coriolis, chiral, three-body, vector Lorentz of the quantum Hall and Aharonov-Bohm effects,... they cannot be shielded.

There are many other points in the essay which might benefit from some further insight, however I'm curious to see what might be learned from your comments on the thread of Michaele and I, am taking a look there now.

Dear Flavio and Chiara,

I like your attempt to separate "formulable theories" from "physical theories" by means of the latter's empirical contents. To distinguish between philosophy and natural science, empirism is necessarily needed. Your attempt of turning the limits of science into a science of limits seems quite obvious for me, since every limit demarcates a distinction and all we have for our scientific endeavor is to make certain reasonable distinctions, hopefully reflecting the distinctions nature does make itself.

I would be interested in how you see the empirical content of the MWI (many-worlds interpretation). By which criteria could one distinguish between the wave function being a physically real entity or being merely a mental construct? Since the MWI facilitates a framework of continous branching of such a wave function and therefore reflects a distinction-process (and moreover is considered as physically realistic, albeit residing in some Hilbert-space), it distincts itself from, say, the Copenhagen interpretation by defining what should be considered as reasonably being 'real' and what not. Since the MWI says that particles are not real, but merely an observer-dependent impression due to decoherence and the Copenhagen interpretation says that physics is not about how the world is, but merely about what we can reasonably say about it - the question seems to boil down for me to properly determine what should be reasonable at all.

Do you think that nature can reasonably be defined as behaving consistently in a logical sense, so that we can progress with finding further fundamental constraints (as opposed to merely practical constraints) and build further theories upon them that always have some empirical content? If this would be the case one should be able to distinguish empirically between the MWI and for example the Copenhagen interpretation. Is there any hint that such a distinction can be made, other than merely looking for some inconsistencies in the lines of arguments for or against one of these interpretations?

At this essay (https://fqxi.org/community/forum/topic/3096) I gave a justification for why I think the MWI might be logically inconsistent. Even if one assumes that an observer's measurement outcome must have been fixed in the past by some initial conditions or simply by the strictly deterministic formalism itself, the Everett interpretation seems to me to shift the problem of an observer into the timeless state of a global wave function. From a bird's view, however, such a global wave function would look (at least for me) as if its branching does increase in one direction, revealing that it is nonetheless bound to some global time. Even if such a wave function contains a non-denumerable 'number' of branches at a distinct point, the assumption of some initial conditions for a specific observer to observe a predetermined measurement result seems to imply for me that these initial conditions had to be infinitely fine-tuned, since there are measurement situations where a result is a superposition of infinitely many possibilities.

Since this contest is an excellent opportunity to ask a professional, I would be happy if you would be able to say how you evaluate the assumption of a psi-ontic global wave function. My impression is that the Everett interpretation rests on the main assumption that this wave function is a real instant of a mathematically infinitely precise working mechanism - a 'mechanism' that needs no time for establishing this precission. In this sense it is a well-defined mathematical object and I ask myself again how to distinguish empirically between such a mathematical object being ontologically real or not.

These questions seem to be important for me, because they touch another important question, namely what should reasonably considered not only as being true in theoretical physics, but moreover whether or not it should be reasonable to assume at all such a concept like 'truth' to be necessarily linked with the behaviour of nature. I think it must be so, and in my own essay I make the case for it. If you like to read and comment on it, I would be glad, since as I outlined in my essay, I think that the quest for some fundamental truth is not a senseless one, but directly touches the heart of science and philosophy. The main point in my essay is, if there is no such 'thing' as fundamental truth (within and about reality), then we have the problem that we never can find out its fundamental absence and in that case I would see no reason why your attempt of an FC-based science should necessarily further produce unambigous FC's. Of couse, it can, but not due to some fundamental truth nature follows, but merely because nature would then be irrational and we couldn't recognize it. So what I describe in my essay boils down to two opposing viewpoints, either one believes in some fundamental truths, or one believes in some fundamental delusions, the latter eventually and unreasonably well suited to camouflage its inextricably paradoxical nature.

I'm in hope for your comments on these issues.

Best wishes,

Stefan Weckbach

Dear Flavio,

I was enticed by your title but disappointed to find your philosophical objections to reductionism. While the particle physics community is VERY presumptuous of their 'dominant' role, it is not because of reductionism.

In fact, reductionism has not proposed a single theoretical development since the mid-80s (other than my own work https://fqxi.org/community/forum/topic/3092 ). The preon approach to reducing the number of fundamental particles was cast aside due to its inability to find a foundational theorem.

The particle physics community suffers from the Gell-Mann syndrome. This is evident in Sabine Hossenfelder's paper, where she argues (feebly) in favor of renormalization, rather than seek to replace it. Specifically, EVERY particle theory advanced for 30-some years has HAD to propose a New Fundamental particle, or several, as Gell-Mann did. (This is actually a requirement enforced by most publishers, to feed the collider community things to disprove!)

But the algebraic group formed by quarks and fermions is (can be formulated to be) Closed. This has nearly been proven empirically by the Higgs discovery.

As such, while we agree that a "philosophical prejudice" must be broken down for real progress to be made, I am certain that your advice is off-target.

Hopefully this contest will help remove the existing prejudices in the field.

I note that academia as a whole is rather biased against innovation, and rarely accepts new ideas from outside its clique. This contest favors works from academia that would otherwise not be funded... a waste of effort?

Best regards,

Wayne Lundberg

p.s. This contest is rather badly biased in its rules, which favor people in large academic institutions over innovators. That is quite evident in the results thus far, and in the fact that it rewards only philosophical writing. It remains to be seen whether it helps get superior ideas reviewed.

Dear Flavio and Chiara,

thank you for sharing your excellent essay, which I really appreciated! From the reading of it I can deduce that we share basic ideas and we see many problems from the same perspective, even if the methodology and the expository method we used are different. In particular, your contribution is much more detailed and informed on the scientific and epistemological literature and demonstrates first-hand knowledge in quantum mechanics. Thus, I think that your paper definitely deserves the consideration it has gained within the community and the public of the contest, to which I join with a very high evaluation.

My best wishes for everything,

Giovanni

Dear Flavio,

Looking back thru our thread...

"I just finish to read your essay, trying to figure out whether I could find there the answers to these misunderstandings on the empirical content, but I didn't. I will comment on the contents of your essay on the dedicate thread, though."

If you have intent to follow up on this, you might find it easy and expedient to check out this brief thread on renormalization in the Linkedin quantum physics group.

https://www.linkedin.com/groups/1892648/1892648-6368178828442890243?midToken=AQGj9NsuXko5pw&trk=eml-b2_anet_digest_of_digests-hero-12-view~discussion&trkEmail=eml-b2_anet_digest_of_digests-hero-12-view~discussion-null-otwg3~jdlyv0eh~d5-null-communities~group~discussion&lipi=urn%3Ali%3Apage%3Aemail_b2_anet_digest_of_digests%3BN95EpJmZQRi3L5YoO7TdpA%3D%3D