Carlo Rovelli’s Radical Perspective on Reality
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The article discusses Carlo Rovelli's radical perspective on reality, where he argues that time is an illusion and reality is relative to the observer, sparking a discussion on the foundations of quantum mechanics and the nature of time.
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Moreover, it's pretty obvious that when they're describing the theory they can not avoid evoking temporal language & metaphors so it's difficult to take them seriously when even they can't avoid describing what's going on w/o referring to time.
I do agree that you can go quite far with calculus, linear algebra, and probability. But I do think that you overstate the case.
¹https://webhomes.maths.ed.ac.uk/~v1ranick/papers/eisenbudhar...
Those rules might be be deterministic or there may be a roll of a dice. Then what we perceive as time is the sequence of states, the memory of previous states. No ticks are needed: there might be no central clock like in CPUs, each part of reality might apply those rules continously and move the global state from one state to another one.
But this is not physics as we are doing it now, it's presocratic philosophy. They got the idea of atoms right among a number of ones that turned on wrong.
but time ticking because of some dynamic interaction mechanism between some things (like a mechanical clock) is very different than some fundamental/abstract/irreducible "time" which just is (like in einstein)
In a universe without states that evolve, you cannot create a clock.
>The more I learn about theoretical physics & physicists the more I'm convinced these people are basically idiot savants.
This is an incredibly bad faith thing to say, when you admit you know nothing about the relevant field.
Physics is hard math, and has been that way for a century. Simpler mechanisms of information description are no longer accurate and unambiguous enough to clearly define what we have the data to demonstrate.
But the public gets really really mad when you tell them "Sorry, you need 8 years of math education to ride this ride" because the public is mostly convinced that math is "useless". So people with adequate training in writing to a lay audience and zero physics training keep asking physicist questions, and the answer is in math nobody will understand, so they have to approximate what math they are trying to convey or describe with some shitty analogy or words that don't actually mean the same thing. The lay public then makes all it's inferences based on broken analogies and comes to outright wrong conclusions.
This is why the lay public is still convinced quantum is magic, or allows faster than light information transmission, or magically speeds up computation, even though the math has always been clear about how that's not what is meant.
Stop thinking that vague words a physicist says are actually meaningful. They are struggling to convey difficult but crystal clear math to an audience that can barely read at a 6th grade level.
There are even "physicists" who have taken frank advantage of this system to make money by lying to the public full stop. People like Michio Kaku. Some of them are nice enough to openly label themselves "futurists", but not all.
Lee Smolin has gone down a different track but with similar spirit of sorts. Carlo poked fun at Lee for all the work they've done together despite disagreeing on so much in his recent talk[1] at Lee's Fest[2].
Smolin has named his approach the Causal Theory of Views, in which he postulates that spacetime emerges from events, ie relational interactions. This[3] interview, which is a few years old now, contains a decent high-level explanation. The idea that kinda overlaps with Rovelli he explains like this:
The theory that I've been looking for would take advantage of the fact that the notion of locality and nonlocality is key to understanding quantum mechanics, and then try to understand that with the lens of the unification of quantum physics with space and time, which is quantum gravity.
In both approaches, there's a principle, which is the idea of relational physics—that the degrees of freedom, the properties of whatever it is that's dynamical that you're studying, arises from dynamical relationships with other degrees of freedom.
In other words, you don't have absolute space, you don't have particles that occupy points or follow paths or trajectories in absolute space. You have many particles which, between them, allow you to define relative motion.
Lee has given several talks[4] at PIRSA since that interview with more details as he's developed his idea.
So while both go hard on the relational aspect, they disagree on some fundamental things. Rovelli thinks time is an illusion, but in Lee's CTV time is real and space is the illusion (emergent).
Who knows if it'll pan out or be a dead end, but since the quantum physics community has been headbutting the fundamental issues with little progress for so many decades, it seems prudent to try some bold approaches.
[1]: https://pirsa.org/25060030
[2]: https://pirsa.org/c25023
[3]: https://www.edge.org/conversation/lee_smolin-the-causal-theo...
[4]: https://pirsa.org/speaker/lee-smolin
A crazy thought I had in my sleep: What if dark matter only exists as a random noise generator to keep the simulation from halting? /s
My brain is weird.
This is kinda what would happen in Penrose's Conformal Cyclic Cosmology[1], as far as I can gather. In his theory, he posits that in the far future, matter has decayed to radiation, and energy has been redshifted into infinity thanks to the expansion of space.
As such, in a local region things would seemingly be frozen in time. Nothing would change, entropy would not increase, and hence no apparent passing of time.
That said, his theory is pretty speculative. But fun to think about.
[1]: https://en.wikipedia.org/wiki/Conformal_cyclic_cosmology
And later:
> Our community has wasted a lot of time searching after speculative ideas. What we need instead is to digest the knowledge we already have. And to do that, we need philosophy. Philosophers help us not to find the right answers to given questions, but to find the right questions to better conceptualize reality.
I think it’s odd that a physicists proposes a new theory without suggesting experiments that could falsify the theory.
The amount of people looking outward only is too damn high, as the saying goes.
and you can rearrange equations to make them better fit together without needing new experiments
Carlo Rovelli on challenging our common-sense notion of time - https://news.ycombinator.com/item?id=17893865 - Sept 2018 (74 comments)
Carlo Rovelli on the ‘greatest remaining mystery’: The nature of time - https://news.ycombinator.com/item?id=17376437 - June 2018 (143 comments)
https://arxiv.org/pdf/2105.13338
And my own personal take on it:
https://blog.rongarret.info/2014/10/parallel-universes-and-a...
Could you please cite the abstract pages instead of the pdf.
The pdf is linked off the abstract page anyway, in case the reader wants to download that after reading the abstract.
The abstract pages usually have other bibliographic goodies that can be easily accessed.
If I had to label him, I'd say he is mostly an anti-realist.
[1] https://www.youtube.com/watch?v=JR2sMeXLuLw [2] https://www.youtube.com/watch?v=3riyyEmWwoY
I especially like 'Quantum Mechanics and Experience' by David Z Albert (he's got a very peculiar style of writing that I enjoy), and 'Quantum Non-Locality and Relativity' by Tim Maudlin.
Not easy reading, but manageable if you have a physics degree.
- First, because it would be a way to test these hypotheses
- Second, because it would dramatically expand humanity's playground, even if it's only in the solar system in the first step.
- Third, because building a Warp drive would be good for the economy. Currently, we have no equivalent to the space race. We have AI, but there are doubts that it will enable more than incremental steps.
- Loop Quantum Gravity
https://en.wikipedia.org/wiki/Loop_quantum_gravity
- Causal Set Theory
https://en.wikipedia.org/wiki/Causal_sets
- AdS/CFT & Tensor Networks
https://qspace.fqxi.org/videos/121/a-tensor-network-approach...
- Relational Quantum Mechanics
The one discussed here
- “It from Qubit”
https://www.scientificamerican.com/article/tangled-up-in-spa...
- Thermodynamic Gravity
https://en.wikipedia.org/wiki/Entropic_gravity
- Noncommutative Geometry
https://en.wikipedia.org/wiki/Noncommutative_quantum_field_t...
Perfectly in line with his political views, when he's a guest on the Italian TV's, or on social media he spend so much time defending the reasons of the Russian in the Ukrainian invasion. With hosts that often asks physics and political questions in the same set, as if his way of looking at reality gives him any ground truth. I'm wondering how much his physics and political views overlap. Such a delusion for me as Italian, I stopped reading his books for this reason and because at some point, after the wonder effect of reading about quantum worlds, I was left with the sensation that I read a lot and nothing at the same time
But I take the point you are making.
Just a quick nitpick as a fellow Italian: “delusion” (“illusione”) is a false friend of “delusione.” Maybe you meant “disappointment”!
There are many concepts like this throughout human history - another one I'm thinking of is the (in the West) monotheistic idea of narrative history/time. By framing time as something that can have a beginning and end, you enable or at least incentivize "progress", and mentally unlock the ability to work toward some idealized future, rather than accepting that time is cyclical and/or without some notion of moving forward.
> Within modern philosophy there are sometimes taken to be two fundamental conceptions of idealism:
> 1. Something mental (the mind, spirit, reason, will) is the ultimate foundation of all reality, or even exhaustive of reality, and
> 2. although the existence of something independent of the mind is conceded, everything that we can know about this mind-independent “reality” is held to be so permeated by the creative, formative, or constructive activities of the mind (of some kind or other) that all claims to knowledge must be considered, in some sense, to be a form of self-knowledge.
Among mainstream philosophical traditions, idealism is IMO the weakest, as it's inevitably solipsistic. Physicalism has become strongest.
Your own perception of the physical world is, by necessity, solipsistic. Your own experience of the physical world is in your own mind. Without that perception, you can’t say it exists.
We know that it’s possible to have this experience of perception without the physical world, as long as your mind exists. In other words, this could all just be a simulation being dumped into your mind without the physical world as you “know” it existing. Hence, idealism.
Whether one is stronger (or more true?) than the other really doesn’t affect how you function within reality - you’re constrained by what you perceive as the physical world.
Physics tends to imagine that a mind is a neutral blank screen that represents reality faithfully and accurately. But that's nonsense. It's a process that imposes certain kinds of perceptions.
The conceptual metaphors we use - position, mass, velocity, time, causality - are products of that process, not fundamental representations.
It's possible other minds have unimaginably different experiences based on unimaginably different metaphors.
Some of those might have potential mappings to our models, others might not.
Per the Wittgenstein, you have, e.g., the "private language" problem: https://plato.stanford.edu/entries/private-language/
Per Heidegger, well, the entire notion of "being-in-the-world" is a response to idealism. This is the notion that we first encounter a shared world of use, tasks, and significance (hammering, writing, speaking with others,) not private "ideas." So the world as you experience it isn't constructed within your head alone; the outside is always with you. You're embedded in an objective field -- or, at the limit, a consensus field.
As a general rule, you can't make sense of science and the commons as purely private occurrences. One's theories are often false; one is often genuinely surprised.
Besides, even classical idealists need something "beyond" representation (Kant's thing-in-itself; Schopenhauer's subliminal Will) to make sense of why experience has the structure it does. That is, the idealist view silently re-imports something non-mental to ground the mental.
Of course, we could be Boltzmann brains, dreaming clouds of charged gas in the sky, or we could be controlled by Cartesian Demons... and that is where strong idealism eventually leads... but I think that these views should be disfavored even on empirical grounds, for instance in your continued existence.
Now, that being said, the remarkable part is that the forgoing conclusion does us zero harm. We can still have the logical predictive fiction that an objective reality exists. What staggers the mind is the corollary that no human has ever erected a truth. Moreover, every intelligent species that ever endeavors to ask these questions will find the same non-answer.
Do you ever ponder that the maths that you try to distill into the “laws of physics” is just too low of a fidelity for such a complicated system?
For example when you capture a gorgeous sunrise/sunset in a photo, and despite you doing every trick under the sun to get a good angle/lighting etc, the photo is never as good as what you experienced in person.
Or maybe you just never experienced the sunrise/sunset shrug.
I don’t think we’ll be able to really discuss the matter so have a good night!
I think you're asking questions that some are afraid to ask.
It appears to me that some people have become accustomed to working with approximations, and have accepted the map for the terrain.
Fundamentally, I don't see how you can use continuous math to explain a discrete system.
No, here we are discussing the formalism without approximations associated with an instance of its approximate application.
And QM says "The map is the terrain".
You might want to be a little more specific, and rely less on approximations.
I am aware of what the Copenhagen interpretation states, thanks
Here we discard Copenhagen and move forward.
Schrodinger/Dirac/Feynman.
A wave is a product, trigonometric functions do not exist.
Gerard hooft was on Curt Jaimungal's youtube channel a while back, I generally agree with him, discrete systems cannot be explained by real numbers, only integers
Hell, you don't need a physics degree for this, nor even QM, just a robust grasp of the limits of empiricism. Hume connected the dots centuries ago.
No. Subjective reality is what we experience as sentients. There must be an object reality and imho that is the only statement of truth that can be uttered in language, with "language" to be understood in the sense that Werner Hisenberg uses that term.
So I'm with Bohr, Hisenberg on this matter. We can not 'presume' to speak of the Real with capital R. It exists but it can not be 'encompassed'.
No vision can encompass Him, but He encompasses all vision. Indeed, He Is the Most Subtle, the All-Aware! - Qur'an - 6.103
If you want to discuss Philosophical/Ontological/Epistemological concepts of Reality/Truth etc. there are far better models in Hindu/Buddhist scriptures. The submitted article itself refers to Nagarjuna's Sunyata and Madhyamaka Buddhist philosophy.
There is violence in every ideology. To deny this is to deny reality. Singling out one group as uniquely prone to violence is both uncivil and dangerous in my view. That does not mean that one cannot point out the shadow side, but one should look in the mirror of one's one preferred ideology, whether that is christianity, atheism, scientism, nationalism, rationalism, etc., before casting blanket aspersions at others.
Justification of one of the biggest, fastest, and most brutal conquests in history? Because everybody who wasn't a Muslim was fair game for killing or slavery? Because all non-Muslim land really belongs to the Muslims?
That's what it actually says.
> Singling out one group as uniquely prone to violence is both uncivil and dangerous in my view.
Something that I very clearly didn't do. And there was nothing lazy about my comparison.
> I happen to familiar with both
I don't think you are. No Quantum Physicist has ever quoted anything from Quran since there is nothing there (it is the youngest of all religions being only from 7th century AD) which has not been already elaborated in Hindu/Buddhist/Greek/Chinese/Christian philosophies/worldviews. That is why most scientists quoted from those ancient scriptures. There is no need to try and hoist your opinions on them.
Moreover the article specifically mentions Carlo Rovelli drawing inspiration from Nagarjuna's Buddhist philosophy and hence that is the model we should look at to try and understand what he means (and not drag in all and sundry others).
> I don't think you are.
How could you possibly know? And frankly, with that handle, it seems you are the one with a "religious" issue.
> No Quantum Physicist has ever quoted anything from Quran
Thank you for motivating me...
What is this, childish echolalia? The "religiosity" was right there in your totally unnecessary quote.
> How could you possibly know?
By inferring from your comment(s), duh!
> And frankly, with that handle, it seems you are the one with a "religious" issue.
What does this even mean? If you are referring to the passage i quote in my HN profile, that is the opposite of "any religiosity". Read the cited book for edification.
> Thank you for motivating me...
Hubris to laughingstock.
And if you appreciate Hindu scripture, that particular quote could have been lifted almost verbatim from the Upanishads.
I don't appreciate the dogmatism that is associated with a lot of orthodox Islam either, but this is something similar to a lot of conservative religious outlooks, as you can find among people identifying as Hindu, Buddhist, Christian, etc. But in fact this particular quote can be seen as antithetical to any such dogmatic position, and it's worthwhile to recognize points of agreement even though you might disagree in other areas.
I would also say that any theory that does not have room to say definitively that I exist is a theory that is obviously contradictory to my experience and is therefore falsified. There has to be room in the theory for at least me. Additionally, I would certainly value much more a theory that has room for the rest of humanity more than one which questions the existence of everyone but me. I am not even sure what the point of a theory would be if it could not account for collaborative science being done.
The "every outcome happens" aspect of many worlds is a lot to accept. Otoh that's what you get if you take quantum states to be ontological and universal. My problem is more to do with how the Born rule falls out. There are some arguments for it based on decision theory, but I find the step from "this is how a rational betting agent maximises winnings" to "this is the objective probability of a scientific observation" uncompelling.
I'm not sure what you mean by "standard QM". There's the mathematical framework - which is effectively a way of calculating probabilities of measurement outcomes - and then there are interpretations, which assign ontological status to some/all of the mathematical objects. Non-locality properly applies to the latter, since you cannot say that the "real" physical state of a particle has changed until you've said which parts of the mathematics are real.
objective
adjective
Not influenced by personal feelings or opinions when considering and representing facts; impartial. “Historians try to be objective and impartial.” Synonyms: impartial, unbiased, neutral, dispassionate, detached. Antonyms: biased, partial, prejudiced.
Existing independently of the mind; actual. “A matter of objective fact.” Synonyms: factual, real, empirical, verifiable. Antonym: subjective.
Grammar. Relating to the case of nouns and pronouns used as the object of a transitive verb or a preposition.
(Yes, I am aware of the otherwise nonsensical concepts "pattern" and "interesting".)
QM, for example, is a totally adequate theory of objective reality! it just describes an objective reality with properties which differ to some degree from those intuitive to creatures at classical scales. It may be inadequate in other respects (not invariant, a little unsatisfying wrt the born rule, etc) but it isn't as if it implies NO OBJECTIVE REALITY.
https://en.wikipedia.org/wiki/Relational_quantum_mechanics
The claim is not that objects don’t exist, just that they don’t have observer independent properties.
I say this because just a few days ago on this forum someone was asserting that without humans the earth would not exist, that human observation instantiates the earth and the earth did not exist before human consciousness.
I would say that QM shows the world is not classical, but it doesn't say there's no objective reality: the predictions it makes about what we observe (reality) are extremely reliable and accurate (i.e. objective).
Yes, those predictions are just probabilistic for any single system, but when you have a lot of systems the probability that you will observe a specific outcome (to within observational error) can approach 1. A lot of our technology, such as lasers, transistors, etc., relies on this. I don't see how you make sense of that while denying there's objective reality.
many worlds posits a single universal quantum state it's just only partially accessible to observers, which is different from saying that it simply doesn't objectively exist.
maybe it depends on your definition of objective
Reproducable reality from x frame seems non-arbitrary if not objective.
But what that means is that we have to readjust our classical conceptions about what a "property of a system" is.
The word "property" in general is just a logical concept, and doesn't carry any intrinsic ontological implications. There can be mathematical properties, physical properties, properties of thoughts and dreams etc., and this way of talking about things doesn't by itself imply any specific ontological interpretation. It's just a feature of the structure of language.
About physical properties specifically, if we derive our concept of physical property from quantum mechanics, instead of trying to retain the inadequate classical meaning, then physical properties are exactly those represented by the state vector: e.g. its projections on to each of the basis vectors corresponding to some observable.
True, as is well-known from the Bell and Kochen-Specker theorems, we can't consistently say that a quantum state has some specific value of its observables independently of interactions with other systems, but this is just the classical conception of a physical property (formalized, e.g., by a real-valued function on phase space).
But quantum mechanics doesn't thereby force us to say that a physical system has no definite properties. Instead, we can reconfigure our conception of physical property to make it compatible with quantum mechanics.
Then in general the properties of quantum states are probabilistic (at least some of them - the dimension of its state space, for example, is not), but the theory unambiguously assigns to a state the probabilities that the various possible measurement outcomes will be observed. These probabilities are among that state's properties, and all indications are that these probabilities are objective features of the state, independently of our ways of representing the state.
In fact the dependence goes in the other direction: this (objectively) probabilistic character of quantum states (among other things, like the quantization of energy exchanges) is what forced us to change the way we think of physical states.
Nevertheless, it was thought (e.g. in the Einstein Podolsky Rosen paper in 1935) that it might be possible to formulate a theory that could reproduce all the correct predictions of quantum mechanics, while also ascribing simultaneous well-defined values to all the physical quantities possessed by a quantum system, i.e a locally realistic theory. These are also known as local "hidden variable" theories, where the idea was that some of the values of the variables might be unobserved simply because of measurement practicalities - we can't measure the spin of a particle along two orthogonal axes simultaneously because the measurement needs a magnetic field gradient along the direction we're measuring in.
Bell derived an inequality that any locally realistic theory must satisfy, and showed that quantum mechanics in fact violates this inequality, so no locally realistic theory can reproduce the predictions of quantum mechanics. Alain Aspect and others later implemented Bell's thought experiment in the lab and showed that the physical world obeys quantum mechanics, and so is not describable by a locally realistic theory.
In my view, none of that shows that there is "no objective reality". Rather, it shows that objective reality is as far as we can tell quantum mechanical, and not locally realistic in the sense described above. It's certainly the case that quantum mechanics requires a modification of the classical concepts of reality, i.e. of classical ideas about what a physical system is, but you would only accept that conclusion if you agree that quantum mechanics is telling you something objective about reality... At least according to how I understand those words.
So I think what people really mean when they say quantum mechanics shows there's no objective reality is just that it contradicts classical conceptions of physical systems, which is clearly true but sounds less sexy and mysterious.
Thus, there is no local theory that has definite experimental results compatible with what is actually demonstrated in labs. Many worlds, to the extent that one can apply any notion of locality to it, avoids this by not having singular, definitive experimental results (all results happen).
I guess you know this, but just to clarify, that's only if the same measurement is performed in the other lab. If the other lab measures an orthogonal spin component, that result can't be predicted at all (I'm assuming entangled spin-1/2 particles for simplicity). It's more precise to say that measurement in the first lab tells you the state in the second lab, and with that information the probabilities for the various possible measurement results in the other lab can be predicted. In particular, if the other lab measures the spin along the same axis, the results can be perfectly correlated, as you say.
So there's some kind of nonlocality, but it's not the kind of nonlocality that makes problems with relativity, because the correlations can't be used to signal or cause any difference in the distant lab, only to predict, in general probabilistically, what would happen in the other lab if some measurements are performed. So entanglement allows this interesting middle ground between a local theory and a theory that's nonlocal in the sense that it would allow nonlocal causation, which is the kind of nonlocality that would worry Einstein. There should be different words for the different kinds of nonlocality, but maybe nonlocal correlation versus nonlocal causation serves the purpose
I recently heard a talk from Tim Maudlin where he mentioned that foliations are the easiest and most natural structures to use to provide nonlocality and, if there is such a thing, maybe there is a clever way of using it to actually communicate and discover the foliation in some sense. He mentioned there is current research on using arrival times which are experimental results outside of the operator formalism, as far as I know. I found an article describing the research:
https://www.altpropulsion.com/ftl-quantum-communication-reth...
I must admit I haven't read the full EPR paper, only post-Bell expositions and excerpts. But you can have perfect spacelike correlations of the same measurement classically as well, e.g. if two particles having opposite (angular or linear) momenta are sent from the midpoint towards distant labs, measuring one momentum will tell you the other one. They must somehow discuss making different measurements no? Maybe they effectively discuss a protocol where the two labs agree on the same sequence of orthogonal measurements. I should read these sources sometime...
Thanks for the ftl reference. It would be astonishing if their hypotheses are borne out. I find it unlikely, but of course the experiments will have to decide, so I'll keep tabs on that. By "foliation" in this context I guess he means a foliation of spacetime amounting to an absolute reference frame. I've seen Tim Maudlin discuss something like that before.
By the way, the article you linked mentions a couple of times the importance of distinguishing signaling from causation or action, but doesn't seem to define how they're distinct. Do you know some more formal article discussing the proposed experiments? The sources given in the article are just to video interviews.
Bell's work was to show that it had to be the nonlocal causation.
>Do you know some more formal article discussing the proposed experiments?
I do not know of an article, but Maudlin's book Quantum Non-locality and Relativity goes through the various notions of locality and what QM says about it. There is a chapter about signaling and another about causation. It also covers the GHZ scheme which is a non-probablistic version demonstrating non-locality. It is pretty clean.
>Do you know some more formal article discussing the proposed experiments?
I have not read them, but my understanding that Siddhant Das is pursuing these and here is a link to his Arxiv papers which talk about arrival time experiments though I do not know if it is directly about these.
https://arxiv.org/search/advanced?advanced=&terms-0-operator...
Local causation is defined as in Bell's Theory of Local Beables, as the probability distribution for values at spacelike separated regions only being correlated with respect to the overlaps in their past lightcones. Or to put it the other way around, there's nonlocal causation if the probability distribution of values in one region depends on values in a spacelike separated region. That's what I'd call nonlocal correlation rather than causation but I guess that's just terminological.
This looks like a pertinent paper from Das but I haven't read through it yet
Arrival Time Distributions of Spin-1/2 Particles (2018) https://arxiv.org/abs/1802.07141
Can’t get on board with that. Relational QM/no objective reality is just one viewpoint, and it’s worth noting it’s not consensus.
To clarify he’s not claiming objects don’t exist, just that they don’t have observer independent properties.
It is fun to try and wrap your head around what no objective reality would mean. To grasp what we already have shown to be true about time being relative, the examples around simultaneity are a great wtf demonstration: https://en.wikipedia.org/wiki/Relativity_of_simultaneity
The process of philosophy involves shedding illusions like words, statements, time, space to reach objectivity. A loop quantum gravity philosopher claiming there is no objective reality could just be an observer stuck at a bottleneck (notice he doesn’t call into question illusory attributes the piece relies on like biographical info).
Barbour’s observation, that quantum appears to demand specialization and record keeping at very unique planes (records are geology, fossils, impressions, photographs) hints that observers are what physical reality is, is counterpoint to “there is no objective reality.”
If reality is non trivially about record keeping, then of course there’s an objective reality, the Darwinian outcome is the objective sum of record keeping and the study of their differences.
https://youtu.be/yqOVu263OSk?si=M3fcLbJneZ0S5Jpq
Adivita Vedanta, Buddhism, mystics and perennial philosophers have been saying this for centuries
https://youtu.be/cwcft4auszA?si=1vYsny6jZb--IE_0
Wolfram is also taking in the same vein but in a different approach
https://youtu.be/8SD9WgPCZ28?si=t8XvVfJV8qi-K_0q
Ie something is up and spacetime is NOT fundamental
[1] https://andercot.substack.com/p/theres-no-single-objective-r...
Taken to its metaphysical conclusion, though, "there is no objective reality" can lead to harm. So, I guess morality is all a matter of perspective? That can be used to justify anything. We do seem to have an emergent reality (at least the one I am experiencing at the moment) that is held in common - just because the underlying mathematics is hard to interpret doesn't justify "anything goes", or my crazy belief is just as good as your crazy belief.
So although it is fun to think about, don't take "there is no objective reality" too seriously - you still have to go to work, you still have to pay your taxes.
Physics can't claim domain over the study of reality and then say that reality can only be studied using mathematical rules. You can either say physics is the study of mathematical physicalism and stick to your mathematical rules, or you can say physics is the study of reality and be open to alternative ideas outside of mathematics to describe reality. Otherwise you're just precluding the conclusion of what you're supposed to be studying, that reality can be described by mathematical rules.
> Taken to its metaphysical conclusion, though, "there is no objective reality" can lead to harm.
So we should hide reality under a rug if it could possibly lead to harm? The truth is the truth, your objective as a scientist should be to follow the evidence not police morality. History shows that the truth tends to lead towards a better world anyway. I'm sure the Church was afraid of the decay of morality from atheists if they learned that God doesn't keep the planets in motion.
I never claimed that physics claims domain over all studies of reality - in fact I quite limited the domain of physics to finding the "best set of mathematical rules" that gives a certain probability of events happening.
>Otherwise you're just precluding the conclusion of what you're supposed to be studying, that reality can be described by mathematical rules.
Just the quantifiable part of reality - the "metaphysics" parts (e.g., why are we here? Is that a sensible question?) aren't the purview of physics (although physicists generally have their own opinions, as does Prof. Rovelli...)
>So we should hide reality under a rug if it could possibly lead to harm? I never said hide it - I said such metaphysical beliefs could lead to harm. So be aware that the popular interpretation of there being no "objective reality" (which relies on interpreting something mathematically rigorous in physics) can be twisted into justification for nearly any action.
Also, the lack of objectivity in the universe doesn't necessarily mean that nihilism is the ONLY way to go. Existentialism, for example, doesn't accept an objective reality either, and folks have found ways to make morality (and even religious faith) fully compatible within that framework.
Obviously, it's not good to delve into metaphysical speculation, as it often clearly leads to junk conclusions written by people who don't have the credentials to account for what the actual science (OR the actual philosophy) says.
But I do wonder what it would be like if modern physicists were more willing to pair up with modern philosophers once in awhile. I would very much love to see a collaboration between the two fields to explore what a subjective universe really MEANS to us as both a species and as moral beings in that universe.
I, very much, would love to see what some of these implications are, as written out by the folks who actually understand the science. Even if there's no true consensus among them, just learning what the different possibilities might be could be very enlightening.
But agree with you in this case. Animals perceive the flow of time because we have memory and prediction abilities. This gives us a psychological arrow that aligns with the thermodynamic arrow.
Concepts in statistical mechanics by Arthur Hobson
Publication date 1971
https://archive.org/details/conceptsinstatis0000arth/page/15...
Concerning the concept of time, it is clear that the generalized second law is related in some manner to the question of the "direction" of time. It is sometimes asserted that the second law explains the distinction between past and future, or that the future may be defined as the direction of increasing entropy. This assertion says that the second law is more fundamental than the distinction between past and future.
It seems to the author that the above assertion is wrong. It was seen in Section 5.2 that the generalized second law is derived from the distinction between past and future; hence the distinction between past and future is more fundamental than the second law.
The following statement seems to be the most fundamental physical assertion which can be made regarding past and future: we can classify all instants t into two categories; the first category contains those instants about which experimental data is (or could be) known, and the second category contains those instants about which no experimental data is known. The first category is conventionally called the "past" and the second is called the "future". The instants may be labeled with real numbers running from -∞ to +∞, in such a way that the "past" instants constitute a set of the form (-∞ < t < t0), and the "future" instants constitute the set (t0 < t < +∞). The choice of the positive direction as the future is purely a convention.
According to Sections 5.2 and 5.4, irreversibility and the generalized second law are derivable from the existence of the above two categories of in-stants: an "information-gathering category" (the past), and a "predictive category" (the future). The existence of these two categories seems to be a fundamental feature of nature, not explainable in terms of the second law or in terms of any other physical law.
For example, if one takes a video of water heated in a bowl then thermodynamics can tell that at the beginning of the video the water is cold, that at a particular timestamp it should boil etc. But thermodynamics cannot explain why I see the water is bubbling with all movement. I.e. with thermodynamics the world is static 4D structure. It does not explain why consciousness perceives 3D slices of that one by one.
Thanks. Great point.Special relativity covers these, I think. Carlo's interview here explains time from special relativity perspective. He doesn't say time doesn't exist or unreal, but we have some misconceptions in our daily Newtonian intuitions.
https://www.youtube.com/watch?v=PuLaUYQFIwg (Sorry if it is already posted in this tread).
> "Why consciousness perceives 3D slices of that one by one."
Philosophicaly not resolved problem, probably. But in general, in physics, entropy production explains this perception, i.e. modern stochastic thermodynamics.
A simplified analogy is a fence with a color gradient from black to white. When one walks along the fence, there is a perception of a color flow from black to white. But there is no flow in reality, just a static gradient with the flow in the eyes of the observer.
Price also pointed out since physics does not explain time flow or even its direction, we cannot rule out existence of creatures with flow of time opposite of ours. Nothing in physics contradicts that.
And then whole notion of entropy is purely statistical property coming from a lack of knowledge of the initial conditions. Both classical systems and quantum wave function of the whole universe follow time-deterministic equations. So any future or past states of the system contains exactly the same amount information and there is no inherent notion of entropy. But since we do not know the initial conditions precisely, we need to apply statistical reasoning which under certain assumptions leads to the notion of entropy and conclusion that in past that was lower.
The best book to get a grasp on the above is Werner Heisenberg's classic Physics and Philosophy: The Revolution in Modern Science. The introduction by Paul Davies itself is worth the price of the book since it highlights the main issues quite clearly.
At the fundamental level quantum systems have an inherent indeterminism (as a consequence of the famous uncertainty principle) which is what we find hard to grasp. It does not mean total anarchy but that you can only calculate relative probabilities of the alternatives in the answer set i.e. it is a statistical theory. Thus it can make definite predictions about sets of identical systems but generally cannot say anything definite about a specific individual system.
For example, an electron doesn't exist as a single thing occupying a specific trajectory around the nucleus. It only exists as a set of potentialities occupying an area of space viz. the so called electron shell. Only when a measurement is made does a electron-with-position or electron-with-momentum can be said to come into existence (since before the measurement there are only probabilities and you cannot measure both position and momentum sharply simultaneously). It is in this sense that the Reality of an electron is said to only exist in the Measurement/Observation and cannot be said to exist otherwise.
The other side of the coin is that, Modern Neuroscience tells us that the Brain itself is wired to Construct Reality from incomplete data and we seek/construct patterns where there are none. See for example Cordelia Fine's A Mind of Its Own: How Your Brain Distorts and Deceives and watch this Ted talk by Susana Martinez-Conde Reality is made of illusions—and we need them - https://www.youtube.com/watch?v=FzDw07RqCSs
This is a great interview and I must say I like the man a lot more than I did before. He has articulated something here that I have long felt: that it is as important in politics as it is in philosophy or theoretical physics to be able to state one's assumptions, to suspend one's assumptions for the sake of argument and to drop/change one's assumptions in the face of evidence.
I feel like this is a vital skill that we, as a society, need now maybe more than ever, in literally any field in which there is any meaningful concept of "correct" (which I think is most fields). I also think it's a skill you basically learn at university - and that that is a problem. I don't know what an approach to cultivating it more widely would look like.
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