*Copenhagen interpretationIt has been completely flipped in an absurd way. Its presented as a serious way to explain or visualize quantum superposition to the public, completely flipping Schrödinger's original intent. Shows like the Big Bang theory popularized this, but also mainstream physics did.Bohmian Mechanics is the completion of this problem. Its the real deal. But mainstream physicists hate it because its imcompatible with relativity. Well Well if only Lorentz had developed an aet*er theory that would have an absolute time...... That would fit really nicely since its equivalent to SR.
>>17036830Hello again my friend. Nobody will ever care about Lorentz aether theory, no matter how hard you larp. It's funny how you think it's going to magically make Bohmian mechanics viable despite being "equivalent to SR".
Big Physics keeping the dyslexic bohms down. Sad.
>>17036840Oh people do care. It's coming back and you won't stop it.Yes the crucial thing is both need an absolute time. That's exactly why these fit together, even if measurements are the same.
and Hardy's apology was meant to illustrate that number theory is useless and then we got cryptography
>>17036848you can't have absolute time, you can't have flat space eitherwhat you can have is local geometry approximating them to Planck scalede Broglie and Dirac already solved physics Einstein couldn't do the maths to extend Dirac's solution but did understand de Broglie and told Copenhagen-ists that they are wrong and stupid, Bohm and Bell rediscovered parts of the solutioninb4 extend to where - the elastic deformation of the aether that we call gravitation needs to be described as a spinor fieldit is not enough to think about it as a vector field, although that works well enough for small enough scalesat bigger scales (galaxy size and beyond basically) the curl of the aether becomes importantone other place where you could probably see this effect at large enough scale to measure is around a spinning black hole (they all have spin, and quite large angular velocities, which should be a hint)
>>17036850Thanks for the answer, yes nobody said its easy but its the right way to start.
>>17036850So our universe can't turn itself into an infinity loop because time would be unevenly displaced if it's not absolute. It needs to be in a bag of premade.
I believe in principle Bohmian mechanics might be made compatible with relativity by, inspired by the Heisemberg picture, using a description of particles evolving backward-on-time
>>17036830>Bohmian Mechanics is the completion of this problemBohmian mechanics is dog shit with all the problems of a wave function formalism and no practical advantage. The only way the formalism is even useful in any sense is to add a restriction that renders it a diet wave function formalism.>inb4 COPEnhagen gibberishliterally irrelevant to the wave function formalism. Bohmian mechanics is used by pen and pencil(neck) physicists who stop at two particle problems and don't understand or care for the real world outside of the scope of sophist navel gazing.
pencil(neck) and paper*, of course.
>>17036830>presented as a seriousBy?
>>17037209Science books, science communication>>17037193>Bohmian mechanics is dog shitSource? You?>no practical advantageHow about not having to use probability theory to describe the universe? How about finally getting rid of the Einstein "Photon" scam, light is a wave there.>The only way the formalism is even useful in any sense is to add a restriction that renders it a diet wave function formalism.Im pretty sure physicists use it to calculate things.>literally irrelevant to the wave function formalism. Bohmian mechanics is used by pen and pencil(neck) physicists who stop at two particle problems and don't understand or care for the real world outside of the scope of sophist navel gazing.But its a realistic formalism, it explicitely cares about the real world. Or explain to me how you model the real world better.
>>17037190Hm maybe but im not sure if thats helpful.
>>17037236>Science booksSuch as?>science communicationLol what?
>>17037193bohmian mechanica iantmean'ttp be practical, it was constructed with making a proof-in-principle about hidden-variable interpretations
The entanglement of two particles' spins would eclipse energy less than the Planck scale, making a single bond.
>>17037239>>science communication>Lol what?google.comIts absuletely everywhere>>Science books>Such as?Ok you got me, got no example for that right now. Its more a "presented to the public in that way" thing. But the mainstream for sure doesnt see it the right way, which is an argumentum ad absurdum.
>>17037268Entanglement works via pilot waves there.
>>17037236 >physicists use it to calculate "things"Source? You? Lmfao>Im pretty sureIn other words you are talking out of your ass. Show me BM being successfully used for a non-trivial molecule or atom. That would require it to solve a fermionic many-body problem for charged particles.. numerically.
>>17037356>Show me BM being successfully used for a non-trivial molecule or atom.You exactly used an example where BM is very bad at. You are an asshole not discussing honestly. It's better at proton transfer, chemical reaction dynamics, and tunneling in molecular systems.
>>17037422>You exactly used an example where BM is very bad at.Remember when I said BM has all the problems of a WF formalism with no practical advantage, and that the moment people try to use it it becomes a diet wave function formalism anyway? In all the examples you named, by your own admission, BM not only becomes a WF formalism but explicitly builds upon one.>It's better at proton transferRequires a potential BM sucks at providing and hence is obtained from wave function based theories>, chemical reaction dynamicsRequires a potential BM sucks at providing and hence is obtained from wave function based theories>, and tunneling in molecular systems.Requires a potential BM sucks at providing and hence is obtained from wave function based theoriesAlso, all of these (for large molecules) often use classical or quasi-classical simulations (which is not BM but an approximation that is independent of the QM formalism used), not because it is the best tool for the job, but because even with smart sampling schemes wave packet dynamics scale at least polynomially with resolution and degrees of freedom.
>>17037426its just a strawman to complain about the practical significance of bohmian mechanics when the value of the theory has nothing to do with practicality.
>>17037426It procides some real advantages in nieches like Lagrange-mesh methods. You are right that its not used that much elsewise. But >>17037459 said it correctly, BM was made to have a realistic view of the world, without hvaing Schrödingers cat as argumentum ad absurdum. Copenhagen interpretation cant be used to develop quantum gravity or to have a realistic model of the universe. Its for calculating.
>>17036830>*opinion disregarded.
>>17037459The fact that your theory cannot be applied without invoking the formalism it was explicitly constructed to replace (for aesthetics reasons and nothing else).We can all pretend application doesn't matter but the fact is that the configuration picture is a fundamental cornerstone of modern chemistry, and it would take a lot of numerical, purely Bohmian ab initio calculations to translate all the concepts without basically just putting wave function pictures into a clunky pilot wave dress. To conclude, Bohmian mechanics has all the problems of wave function formalisms and no practical advantage. I rest my case.>>17037464Copenhagen as no relevance to WF formalism as stated in my initial post. Lest I am mistaken the Lagrange Mesh method is one of the many adaptive quadrature schemes out there. What does it do for it that you can't have from a (quasi-)classical approximation? >BM was made to have a realistic view of the worldA bold claim for a theory that asserts the existence of quantum non-equilibrium. It's also worth noting that the WF formalism that BM ultimately just replicates is simply unattractive for many reasons to begin with (for high energy physics), which is why people moved on to second quantization pictures. Do I wanna know what pilot fock space abominations BM people cooked up?
>>17037485it wasnt invented to replace orthodox formalism but show that underlying hidden variables can reproduce quantum behavior
>>17037577true, I shouldn't sneak in historical revisionism, while aesthetics (what I would label as such) played a role in its adoption, neither broglie nor bohm were cranks. I stand by the rest, however.
>>17037485>>BM was made to have a realistic view of the world>A bold claim for a theory that asserts the existence of quantum non-equilibrium.There is a clear definition of "realistic" and Bohm hits it while COPEnhagen/many worlds do not.>>17037485>What does it do for it that you can't have from a (quasi-)classical approximation?I cant remember now but its something, we would have to look it up.
>>17036830>>17036830
>>17037710>There is a clear definition of "realistic"I have yet to see a "clear definition" of that sort that does not amount to BM setting the finish line behind itself. QNE and non-locality are both very sore spots of the theory. I would call it a solution looking for a problem but this solution is clearly happy single. To briefly return to Copenhagen, it is a fundamental mistake to consider the Born rule tied to the CI. Until the existence of QNE is verified, asserting QE is, at its core, just a reiteration of Born. One thing that is commonly overlooked is that nothing about WF formalisms is intrinsically indeterministic. A wf known at t=0 is perfectly known for all future moments in time. That is, objectively, determinism. Measurement is, objectively, a fundamentally thermodynamic process. As such Born is not an axiom (or a postulate) but ought to be a corollary, but that is an entirely separate discussion. Born is a shorthand and people can't be bothered to clean it up, but BM does not solve that.>we would have to look it up.Unfortunate with how modern web search is, but I'll have you know that from what i've seen it's the most interesting remark on BM someone made on the subject in ages.
>>17036830what was Schrödinger's cat's name. is dark matter the same as phlogiston. also, what is the inverse of null infinity
>>17037787why is QNE sore spot?
>>17037787>Measurement is, objectively, a fundamentally thermodynamic process. As such Born is not an axiom (or a postulate) but ought to be a corollary, but that is an entirely separate discussion. dont even know what youre saying here or logic behind ityeh wavefunctions are deterministic evolvebut measurements are indeterministicthis is crux of measurement problem and many worlds has not given convincing account how to reconcile them either
>>17037787>I have yet to see a "clear definition" of that sort that does not amount to BM setting the finish line behind itself.Well i cant help you here, but i think realism is a great plus, i really dont like these subjective theories where its all just probabilities>>17037787>QNE and non-locality are both very sore spots of the theoryI mean yes, unless you combine it with an lorentzian aether. Then its suddenly less sour.>WF formalismsNot too sure about all this>the most interesting remark on BM someone made on the subject in ages.Thanks
>>17037934its not less sour tho because lorentzian aether requires revisionism of current relativity and non-locality also revisionism about how fast information can travelboth these fings are undesirable imo
>>17037306>google.com>Its absuletely everywhereGoogle.com is a predecessor of AI; it feeds you back a loop of feedback-nonsense. How does it have anything to do with "seriousness"?Also I feel like you're just rehashing Gribbin's pop-sci kittens book, which I'm quite sure I read as a young lad back when the earth was still cooling. I don't have the book at hand, but wasn't Bohm his childhood role model, or was that someone else?
>>17036830>>17037945Hmm.. You aren't just spinning up cotton candy from an old paperback, now, are you?
>>17036830Most of the "spooky" shit goes away when you imagine every quantum field as a sea of virtual particles. Dirac was way ahead of his time and probably could've come up with QFT all on his own if he didn't have to waste his time proving himself to his peers who were either too dumb to understand him or actively tried (and failed) to shoot down his ideas because they introduced complexities that they didn't want to deal with.
basil hiley and bohm undivided universe is the definitive classic
you can get whole bpok free pdf from university bruxelles website booklist>>17038012qft doesnt take away any spooky shit ot people still wouldnt be arguing about it today
>>17038028what book
>>17038031undivided universe
>>17037923Quantum equilibrium (QE) is asserted for the theory to agree with experiment, which is (as I said) basically just reiterating born rule. Yet this assertion is not considered as part of the theory. If QNE is real then it ought to be experimentally verifiable, and more importantly, there should be concrete approximations and conditions that determine when QNE effects can be discarded. As things stand we are in an awkward position of>>Asserts QE every time BM is invoked>Doesn't that make QE a postulate akin to Born?>>No because QNE is real>May we see it?>>No.
>>17037927>dont even know what youre saying here or logic behind itMeasurement is not some pixie dust bs that needs a spurious axiom, which is why I consider the Born rule a teaching tool and not much more. A real, actual measurement in the physical world is coupling a quantum system to a well-designed bath (the measuring device, which is a macroscopic object with bulk properties). Wave function "collapse" is therefor in actuality a relaxation process. As such the correct treatment of measurement would require the study of thermodynamic relaxation of a subsystem within a larger quantum system (including the observer). You could argue this is similar to many worlds, of course. Though there is actually a very important application to all this beyond interpretations. Moderate to large molecules (N>10) often are very thermodynamic in nature in the sense that functional behave like coupled baths (for example two methyl groups of a carbohydrate rotating and vibrating independently). Given how classical simulations tend to be qualitative (albeit far from quantitative) for molecules of that size suggests that a bulk observer within a quantum system experiences "measurements" classically from their own frame of reference. That is a bold claim to make though,>>17037934Does said aether imply that QNE does not exist, or provide a falsifiable prediction of a QNE effect that can be measured? If not, it does not help with it. >Not too sure about all thisAll of this is extremely technical, I don't blame anyone who hasn't spent years and years with this to find it hard to digest in an off the cuff format like this.
functional groups*
>>17038165Ok but the whole point of BM was to show that a realisitic universe is possible, that its not ferutes by quantum mechanics. I think you got it the wrong way around, its not a postulate, its showing that the opposite is not necessary.>If QNE is real then it ought to be experimentally verifiableWell this is where physics gets on sided. Because i can just as well claim>If QNE is NOT real then it ought to be experimentally verifiableIts just an alternative postulate to the born rule as far as i understand it.Because philosophically i think it makes more sense that its real.
>>17038194>Does said aether imply that QNE does not exist, or provide a falsifiable prediction of a QNE effect that can be measured? If not, it does not help with it.No, its just philosophically more fitting. But as i said before, and im pretty sure im right here, QNE is just as falsible or non falsible then borns rule.
*falsifiable
>>17038165i dont relly understand your logic herepostulating quantum equilibrium isnt relly different from any other postulate you need to invoke for any interpretation of QM or even QM itselfas i understand it, bohmians dont NEED to demonstrate QNE, but it is just a potential avenue where the theories could differ.but at same time im not sure why bohmians must allow for QNE rather than just have the theory be in QE all the time
>>17038194>As such the correct treatment of measurement would require the study of thermodynamic relaxation of a subsystem within a larger quantum system (including the observer). sure but just saying that you can describe measurment as a deterministic unitary evolution does nothing to explain the statistics of measurement. how can probabilistic statistics be a corollary of a deterministic evolution? that doesnt make sense, which is why additional interpretation is required, and the fact that many worlds doesn't convincingly produce the born rule as a natural corollary just further emphasizes how difficult it is to reduce QM entirely to deterministic unitary evolution. it simply cant account for what people empirically observe on its own
>>17038199>a realisitic universerealism has many definitions is the point, BM, to my knowledge, violates what is called local realism, for example. The fact these terms are tied to a colloquial term and its connotation does a lot of heavy lifting and has little to do with actual philosophy. It is more useful to talk about specific properties of a theory (locality, contextuality/"counterfactual definiteness",...).Verifying a thing to exist and verifying a thing not to exist are categorically different problems for an empirical science, it is not that simple. Accepting QE as a postulate essentially outs QNE as an artifact of the theory.I've seen flavors of BM that are experimentally falsifiable because of this, as they yield results that disagree with standard QM predictions. Relativistic extensions of BM come to mind, but this is uncomfortably far from my field of expertise.>>17038288>as i understand it, bohmians dont NEED to demonstrate QNE, but it is just a potential avenue where the theories could differ.I have always encountered bohmian theories insisting on QNE, this is what these remarks in particular are getting at. But I feel like I am barking up the wrong tree with this, I think both of us would be perfectly fine with BM+no QNE with everything else requiring serious experimental investigation for any useful insights. I would say that experimental verification of QNE would instantly qualify as the greatest physics discovery of the decade though, if not the century, should it come to it. As critical as I am of BM for it simply being a clunky formalism for the aforementioned reasons, if QNE turned out to be actually a real thing I would definitely applaud it.
>>17038200>QNE is just as falsible or non falsible then borns rule.QE is, in essence, QNE would yield something that disagrees with wf-based QM and as such would yield something else, see above.>>17038298>how can probabilistic statistics be a corollary of a deterministic evolution? The core issue is the rigorous definition of relaxation: it's been a decade since I last looked at this seriously. At its core the issue is that system and bath remain a complete wave function in this picture and as such the statistical nature of the observation translates into conditions the local amplitude of the total wf has to satisfy. In other words a relaxation within the system corresponds to a localization in phase space the wave function passes through. Such effects are observed for real world quantum phenomena; if a chemical reaction has to overcome a high-lying transition state that is very confined in phase space, a lot (if not all) information that the wave packet carried before passing the choke point is lost. You can expand the WF at the choke point where it must be very localized: since the density of local eigenstates there is low (as a consequence of localization), a low-energy wave packet cannot populate many local states, and the fine details of the wave packet are lost in the overtones with nigh zero amplitude. Born becomes a corollary in a statistical setting as long as you can show that the total wave function's components after a measurement happened inside it have an amplitude that is a reasonable function (e.g. proportional to) the transition amplitude of the subsystem into one of its eigenstates for the observable. In principle the theory for this is all there but I have never seen it written down cleanly, which is a shame.
>>17038333>BM, to my knowledge, violates what is called local realism, for example.Yes true its non local. But even copenhagen can be non local, depeding on how you define locality, because of quantum entanglement.>Accepting QE as a postulate essentially outs QNE as an artifact of the theory.>>17038355Ok true but this too is basically philosophy or preference, i have not seen a proof for one of these.
>>17038366>because of quantum entanglement.True, but it kinda makes me want to add a complete aside. It's not really something you said but something that pisses me off reading on this board. Einstein's original criticism of "spooky action at a distance" is, in short, retarded, because standard QM is non-relativistic. To be upset that a formalism that isn't (cannot) be Lorentz-invariant has instantaneous information transfer is disingenuous at best. Length scales of [math] c\cdot t [/math] are outside the scope of a non-relativistic theory, and I could trivially write down bogus classical mechanics setups where information travels faster than light. As far as I know measurement operators in theories that are Lorentz-invariant commute, which addresses the bogus complaint without changing anything that actually upset him about the theory.It's so tiring to read, feel free to tell others when you catch them parroting it.
>>17036830the universe doesn't care what schrodinger's intent was
test
>>17038414If you want to defend COPEnhagen with that, thats a stupid remark. Because its a philosophical debate mostly currently and he had a good argument why the universe does not work this way.
>>17038395fink you need to read some bell who shows once and for all that we cant have a causally local theory in the sense of hidden variables whether fings commute across space or "signalling" is not allowed is the true bogus fing coz they don't stop bell-violating probabilities that are incompatible with regilar conceptions of local causationthe only other avenues are also all bogusnot even gonna start on superdeterminismwavefunction realism doesnt help either coz even if you reject non-local collapse you still have a non-local object that changes wiv measurement which imo is just as bad. which is why i fink many worlds is not actually a truly local theory even tho many proponents claim it isyou can reject wavefunction realism but without an underlying explanation, this doesnt solve anyfingand then adding that underlying explanation basically just goes back to the beginning where local hidden variables are just not allowed
>>17038447Oh I am well aware of bell but those are all different cans of worms, the above thing is just a bugbear of mine. I am not a fan of hidden variables, period. I find it clunky, personally.On an unrelated note, KvN classical mechanics is really fucking neat. A classical wf formalism would do physics undergrads some good.
>>17038448existence of KvN classical is good argument that one should not endorse wavefunction realism imoand shows main difference between qm and classical is commutation relationsone can also have analogously basically a KvN-type formulation of classical electrodynamics which give more insight into differences between certain classicla and quantum theories.see daniel piasecki papers wivin last 2 years, e.g. https://arxiv.org/abs/2501.01995v1
>>17038450WF realism is intrinsically absurd because it is pretty damn hard to find a more ill-behaved pair of operators than x,p. That is to say, I would not prescribe [math]\Psi(x) := \langle x \vert \Psi \rangle [/math] physical meaning, just like I wouldn't consider a lagrangian to be more real in Cartesian coordinates than it is in spherical.Worse, the wf representation is less than useless for Lorentz-invariant formulations for obvious reasons. A very interesting paper by the way, thanks for sharing.
Did anyone actually bother to translate second quantization into a bohm setting? Because if not there is no way to express high energy physics in it, not meaningfully.
>>17038494for stochastic generalizations of bohm has been done
>>17038659How does it deal with the creation/annihilation of particles?
