Super determinism

Get your science fix here: research, quackery, activism and all the rest
Al Capone Junior
Clardic Fug
Posts: 151
Joined: Wed Dec 11, 2019 6:40 pm

Super determinism

Post by Al Capone Junior » Wed Feb 02, 2022 2:42 am

I know you guys will love [to argue over] this one.

Does Superdeterminism save Quantum Mechanics? Or Does It Kill Free Will and Destroy Science?

I don't have any particular insights here. But the idea that free will is not an actual thing is interesting.

If there's already a discussion about this, transport this post to that location immediately

User avatar
Martin Y
Stummy Beige
Posts: 2762
Joined: Mon Nov 11, 2019 1:08 pm

Re: Super determinism

Post by Martin Y » Wed Feb 02, 2022 11:56 am

Thanks for posting it. I was with her on the point that free will is just an irrelevant distraction in the argument about determinism but she lost me at "What a quantum particle does depends on what measurement will take place".

I suspect what she was saying is that the measuring process, whatever it is, is an interaction which changes what the particle does. But she doesn't quite address that, explaining instead that how you choose what to measure isn't constrained by the result of what you choose, which is what distracts people into free will arguments.

User avatar
jimbob
Light of Blast
Posts: 4512
Joined: Mon Nov 11, 2019 4:04 pm
Location: High Peak/Manchester

Re: Super determinism

Post by jimbob » Wed Feb 02, 2022 12:56 pm

I don't think that hidden variables make sense.

If the big bang was uniform in the very start then I struggle to see how any purely deterministic process creates structure - especially structure that isn't symmetrical. However random events shortly afterwards could create structure.
Have you considered stupidity as an explanation

User avatar
shpalman
Princess POW
Posts: 7556
Joined: Mon Nov 11, 2019 12:53 pm
Location: One step beyond
Contact:

Re: Super determinism

Post by shpalman » Thu Feb 03, 2022 9:19 am

I don't think there's anything truly random. What we refer to as random usually just means that we don't know enough about the system and its initial conditions in order to predict it. Quantum mechanics itself has completely deterministic evolution of the time-dependent Schrödinger equation, for example, but the "randomness" enters because we can't be bothered to model the whole measurement process as a quantum mechanical interaction all the way up to the macroscopic scale. So we fudge it by considering a simple quantum system in a classical macroscopic universe and it leads to these issues in how the wavefunction is supposed to "collapse".

We've already ruled out certain classes of Hidden Variable theory, but those relate to the particle secretly "knowing" what it's going to do in a way which isn't manifest in its own wavefunction, not the wavefunction of the rest of the universe (which, if you're deterministic, "knows" everything).

Wavefunction collapse definitely isn't a real thing because it's supposed to happen everywhere simultaneously, and that's not consistent with Special Relativity. However, that doesn't seem to mean that wavefunctions can't travel backwards in time just as easily as they travel forwards or something. Just that they can't travel "instantly".

I do have a lot of time for Sabine's blog, though.
But if you want to find out whether measurement outcomes are actually determined, you have to get out of the chaotic regime. This means looking at small systems at low temperatures and measurements in a short sequence, ideally on the same particle. Those measurements are currently just not being done. However, there is a huge amount of progress in quantum technologies at the moment, especially in combination with AI which is really good for finding new patterns...
This is quantum computation, basically. Or rather, the physical testing of quantum computing hardware. So we'll see what happens, because there will be a lot of this going on over the next few years.
having that swing is a necessary but not sufficient condition for it meaning a thing
@shpalman@mastodon.me.uk

User avatar
dyqik
Light of Blast
Posts: 6430
Joined: Wed Sep 25, 2019 4:19 pm
Location: A rock in the middle of the Pacific
Contact:

Re: Super determinism

Post by dyqik » Thu Feb 03, 2022 2:00 pm

shpalman wrote:
Thu Feb 03, 2022 9:19 am
We've already ruled out certain classes of Hidden Variable theory, but those relate to the particle secretly "knowing" what it's going to do in a way which isn't manifest in its own wavefunction, not the wavefunction of the rest of the universe (which, if you're deterministic, "knows" everything).
I'm not sure that this is even as simple as you state here. Most of the universe is not, and never has been, causally connected to our observable universe, so the definition of "rest of universe" is complicated. It differs for a quantum state of a particle localized in M87 vs the quantum state of a particle localized here.

General relativity is even more complicated to make standard quantum mechanics work with than special relativity, and probably needs quantum theory to be altered, even before you look at the measurement problem.

User avatar
jimbob
Light of Blast
Posts: 4512
Joined: Mon Nov 11, 2019 4:04 pm
Location: High Peak/Manchester

Re: Super determinism

Post by jimbob » Thu Feb 03, 2022 3:26 pm

I still cannot see how you get structure from the big bang unless you introduce random events near the start. At the very least, any structure that is not periodic.

I also don't see why this would be problematic. Either you go back to setting up the starting conditions, and then their starting conditions, or you say that at some level - actually stuff does happen randomly.
Have you considered stupidity as an explanation

Millennie Al
Dorkwood
Posts: 1544
Joined: Mon Mar 16, 2020 4:02 am

Re: Super determinism

Post by Millennie Al » Fri Feb 04, 2022 12:28 am

jimbob wrote:
Thu Feb 03, 2022 3:26 pm
I still cannot see how you get structure from the big bang unless you introduce random events near the start. At the very least, any structure that is not periodic.
Structure means information. Information can be created by randomness or be present already. So if there is true randomness, it can be responsible for the structure: otherwise the information was present at all times. It has been hypothesised that information might be conserved.

IvanV
After Pie
Posts: 1731
Joined: Mon May 17, 2021 11:12 am

Re: Super determinism

Post by IvanV » Fri Feb 04, 2022 9:45 am

shpalman wrote:
Thu Feb 03, 2022 9:19 am
I don't think there's anything truly random. What we refer to as random usually just means that we don't know enough about the system and its initial conditions in order to predict it. Quantum mechanics itself has completely deterministic evolution of the time-dependent Schrödinger equation, for example, but the "randomness" enters because we can't be bothered to model the whole measurement process as a quantum mechanical interaction all the way up to the macroscopic scale. So we fudge it by considering a simple quantum system in a classical macroscopic universe and it leads to these issues in how the wavefunction is supposed to "collapse".

We've already ruled out certain classes of Hidden Variable theory, but those relate to the particle secretly "knowing" what it's going to do in a way which isn't manifest in its own wavefunction, not the wavefunction of the rest of the universe (which, if you're deterministic, "knows" everything).

Wavefunction collapse definitely isn't a real thing because it's supposed to happen everywhere simultaneously, and that's not consistent with Special Relativity. However, that doesn't seem to mean that wavefunctions can't travel backwards in time just as easily as they travel forwards or something. Just that they can't travel "instantly".
Particle decay does a good job of appearing to be perfectly random. If it wasn't actually random, but a deterministic system creating the appearance of randomness, then there would have to be some kind of organisation between the individual particles, rather than the particles behaving independently, so that they could choreograph that appearance of randomness so perfectly. The whole lot of them would have to be entangled over a sufficiently broad area. Mr Occam wouldn't like that kind of an explanation for it.

Perhaps you can explain what I'm missing.

My father tells a silly story about being viva'ed for his Manchester physics degree by Brian Pippard, then Plummer Professor of Physics at Cambridge, later Cavendish Professor, with some colleagues. Vivas by external examiners were routine in those days. They were making initial polite conversation to calm the proceedings, and Pippard asked what my father had found difficult in his course. My father said that he never really understood quantum mechanics. Pippard replied, well none of us really understand that, do we, and the examiners laughed among themselves briefly before getting down to business.

My father felt it an undeserved compliment that he might have the same kind of not-understanding that they had. Especially as he was about to be awarded a 3rd class degree. But he discovered that not understanding quantum mechanics, even at a different level from them, was no impediment to understanding enough about the behaviour of radioactive materials to be able to have a career in nuclear power.

User avatar
shpalman
Princess POW
Posts: 7556
Joined: Mon Nov 11, 2019 12:53 pm
Location: One step beyond
Contact:

Re: Super determinism

Post by shpalman » Fri Feb 04, 2022 10:33 am

IvanV wrote:
Fri Feb 04, 2022 9:45 am
shpalman wrote:
Thu Feb 03, 2022 9:19 am
I don't think there's anything truly random. What we refer to as random usually just means that we don't know enough about the system and its initial conditions in order to predict it. Quantum mechanics itself has completely deterministic evolution of the time-dependent Schrödinger equation, for example, but the "randomness" enters because we can't be bothered to model the whole measurement process as a quantum mechanical interaction all the way up to the macroscopic scale. So we fudge it by considering a simple quantum system in a classical macroscopic universe and it leads to these issues in how the wavefunction is supposed to "collapse".

We've already ruled out certain classes of Hidden Variable theory, but those relate to the particle secretly "knowing" what it's going to do in a way which isn't manifest in its own wavefunction, not the wavefunction of the rest of the universe (which, if you're deterministic, "knows" everything).

Wavefunction collapse definitely isn't a real thing because it's supposed to happen everywhere simultaneously, and that's not consistent with Special Relativity. However, that doesn't seem to mean that wavefunctions can't travel backwards in time just as easily as they travel forwards or something. Just that they can't travel "instantly".
Particle decay does a good job of appearing to be perfectly random. If it wasn't actually random, but a deterministic system creating the appearance of randomness, then there would have to be some kind of organisation between the individual particles, rather than the particles behaving independently, so that they could choreograph that appearance of randomness so perfectly. The whole lot of them would have to be entangled over a sufficiently broad area. Mr Occam wouldn't like that kind of an explanation for it.

Perhaps you can explain what I'm missing.
Free neutrons aren't stable; they decay to protons with a half life of about 15 minutes. Free protons are stable. But a deuteron (bound state of a proton and a neutron, the nucleus of deuterium) is indefinitely stable. So there's obviously enough choreography between the neutron and the proton that the neutron doesn't decay. When you get up to isotopes like carbon-11, nitrogen-13, oxygen-15, or sodium-22 for example, protons decays to neutrons in those.

Going back to the double-slit experiment, done with one particle at a time, each particle gives a single spot on the detector in a "random" position but when you average over lots of particles the inteference fringes are visible. How does each particle behave randomly but still manage to "choreograph" with the ones before it and the ones after it in order that the average gives the right answer?
having that swing is a necessary but not sufficient condition for it meaning a thing
@shpalman@mastodon.me.uk

User avatar
shpalman
Princess POW
Posts: 7556
Joined: Mon Nov 11, 2019 12:53 pm
Location: One step beyond
Contact:

Re: Super determinism

Post by shpalman » Fri Feb 04, 2022 10:34 am

dyqik wrote:
Thu Feb 03, 2022 2:00 pm
shpalman wrote:
Thu Feb 03, 2022 9:19 am
We've already ruled out certain classes of Hidden Variable theory, but those relate to the particle secretly "knowing" what it's going to do in a way which isn't manifest in its own wavefunction, not the wavefunction of the rest of the universe (which, if you're deterministic, "knows" everything).
I'm not sure that this is even as simple as you state here. Most of the universe is not, and never has been, causally connected to our observable universe, so the definition of "rest of universe" is complicated. It differs for a quantum state of a particle localized in M87 vs the quantum state of a particle localized here.

General relativity is even more complicated to make standard quantum mechanics work with than special relativity, and probably needs quantum theory to be altered, even before you look at the measurement problem.
What you mean I didn't just manage to unify quantum mechanics and gravity just now in a short forum post.
having that swing is a necessary but not sufficient condition for it meaning a thing
@shpalman@mastodon.me.uk

User avatar
jimbob
Light of Blast
Posts: 4512
Joined: Mon Nov 11, 2019 4:04 pm
Location: High Peak/Manchester

Re: Super determinism

Post by jimbob » Fri Feb 04, 2022 10:48 am

shpalman wrote:
Fri Feb 04, 2022 10:33 am
IvanV wrote:
Fri Feb 04, 2022 9:45 am
shpalman wrote:
Thu Feb 03, 2022 9:19 am
I don't think there's anything truly random. What we refer to as random usually just means that we don't know enough about the system and its initial conditions in order to predict it. Quantum mechanics itself has completely deterministic evolution of the time-dependent Schrödinger equation, for example, but the "randomness" enters because we can't be bothered to model the whole measurement process as a quantum mechanical interaction all the way up to the macroscopic scale. So we fudge it by considering a simple quantum system in a classical macroscopic universe and it leads to these issues in how the wavefunction is supposed to "collapse".

We've already ruled out certain classes of Hidden Variable theory, but those relate to the particle secretly "knowing" what it's going to do in a way which isn't manifest in its own wavefunction, not the wavefunction of the rest of the universe (which, if you're deterministic, "knows" everything).

Wavefunction collapse definitely isn't a real thing because it's supposed to happen everywhere simultaneously, and that's not consistent with Special Relativity. However, that doesn't seem to mean that wavefunctions can't travel backwards in time just as easily as they travel forwards or something. Just that they can't travel "instantly".
Particle decay does a good job of appearing to be perfectly random. If it wasn't actually random, but a deterministic system creating the appearance of randomness, then there would have to be some kind of organisation between the individual particles, rather than the particles behaving independently, so that they could choreograph that appearance of randomness so perfectly. The whole lot of them would have to be entangled over a sufficiently broad area. Mr Occam wouldn't like that kind of an explanation for it.

Perhaps you can explain what I'm missing.
Free neutrons aren't stable; they decay to protons with a half life of about 15 minutes. Free protons are stable. But a deuteron (bound state of a proton and a neutron, the nucleus of deuterium) is indefinitely stable. So there's obviously enough choreography between the neutron and the proton that the neutron doesn't decay. When you get up to isotopes like carbon-11, nitrogen-13, oxygen-15, or sodium-22 for example, protons decays to neutrons in those.

Going back to the double-slit experiment, done with one particle at a time, each particle gives a single spot on the detector in a "random" position but when you average over lots of particles the inteference fringes are visible. How does each particle behave randomly but still manage to "choreograph" with the ones before it and the ones after it in order that the average gives the right answer?
Doesn't that just tell you that it's behaving as both a particle and a wave and the wave is related to the probability density function?

Don't delocalised electron clouds, in your "favourite" substance, graphene, for example show that it's not just us that can't tell where the electron is and its momentum, but the electron itself or the universe itself doesn't either?
Have you considered stupidity as an explanation

User avatar
shpalman
Princess POW
Posts: 7556
Joined: Mon Nov 11, 2019 12:53 pm
Location: One step beyond
Contact:

Re: Super determinism

Post by shpalman » Fri Feb 04, 2022 11:05 am

A point regarding entanglement over long distances, i.e. two photons created with complementary polarizations in which measuring one means the other one has to be the opposite. When you measure one of them, you've actually got no way of knowing whether the other one has been measured or not "already"* i.e. you don't know if you're the one collapsing the wavefunction or the other guy already collapsed it. In fact this probably makes no sense to even say, given the * below.

You only find out about the correlations between the measurements if you and the other observer are subsequently able to communicate and compare notes.

* - two space-like separated events are only simultaneous in one reference frame; there are frames in which the two events happen the other way around. Photons travel at the speed of light in all frames though, but if we did the experiment with e.g. two electrons emitted with opposite spin states (don't know if double beta decay actually does this) then there's probably a frame in which it looks like a positron being absorbed and an electron being emitted.
having that swing is a necessary but not sufficient condition for it meaning a thing
@shpalman@mastodon.me.uk

User avatar
shpalman
Princess POW
Posts: 7556
Joined: Mon Nov 11, 2019 12:53 pm
Location: One step beyond
Contact:

Re: Super determinism

Post by shpalman » Fri Feb 04, 2022 11:45 am

jimbob wrote:
Fri Feb 04, 2022 10:48 am
shpalman wrote:
Fri Feb 04, 2022 10:33 am
IvanV wrote:
Fri Feb 04, 2022 9:45 am

Particle decay does a good job of appearing to be perfectly random. If it wasn't actually random, but a deterministic system creating the appearance of randomness, then there would have to be some kind of organisation between the individual particles, rather than the particles behaving independently, so that they could choreograph that appearance of randomness so perfectly. The whole lot of them would have to be entangled over a sufficiently broad area. Mr Occam wouldn't like that kind of an explanation for it.

Perhaps you can explain what I'm missing.
Free neutrons aren't stable; they decay to protons with a half life of about 15 minutes. Free protons are stable. But a deuteron (bound state of a proton and a neutron, the nucleus of deuterium) is indefinitely stable. So there's obviously enough choreography between the neutron and the proton that the neutron doesn't decay. When you get up to isotopes like carbon-11, nitrogen-13, oxygen-15, or sodium-22 for example, protons decays to neutrons in those.

Going back to the double-slit experiment, done with one particle at a time, each particle gives a single spot on the detector in a "random" position but when you average over lots of particles the inteference fringes are visible. How does each particle behave randomly but still manage to "choreograph" with the ones before it and the ones after it in order that the average gives the right answer?
Doesn't that just tell you that it's behaving as both a particle and a wave and the wave is related to the probability density function?
"particle" and "wave" are answers to two different (and mutually exclusive) questions which you can ask the wavefunction. If I ask the wavefunction "where is the particle?" (operate on the wavefunction with the position operator) I get an answer "it's particle and it's here". If I ask it "what's the wavelength of the wave?" (operate on the wavefunction with the momentum operator) I get an answer "it's a wave and it's wavelength is this". It's obvious that particle-like states should be the answer to the question "where is the particle?" and wave-like states should be the answer to the question "what's the wavelength?" but the wavefunction can't be in a particle-like state and a wave-like state at the same time (or rather, it can't be in an eigenstate of the position operator and of the momentum operator at the same time because they're non-commuting operators). Rather you'll have a "wavepacket" which is spread out in position and contains a spread of wavelengths.

https://twitter.com/quant_phys/status/1 ... 5022415873

(What annoys people is that from the point at which you make the measurement, the system evolves from either the particle-like state or the wave-like state you just measured it to be in, not the underlying probability distribution it was in before. That's the "collape" of the wavefunction. If you ask which slit the particle went through, you get a particle-like answer, and the wave-like interference pattern goes from a double-slit one to a single-slit one.)

In the double-slit one-at-a-time experiment is that the particle is obviously "wide enough" that it goes through both slits i.e. wave-like but then by triggering one detector pixel it's implied that all of it is now in one very tightly-localized position i.e. particle-like.** (That detection would initially be a quantum interaction, i.e. a photon arriving in a semiconductor and generating an electron-hole pair or a charged particle knocking an electron off its atom, and then this needs to get multiplied or amplified into something detectable/visible (e.g. the single liberated electron causing an avalanche of more electrons).)

Yes, there's an interpretation in which particles are particles but they follow the wavefunctions; not sure about the current status of this but you'll note it has to be "non-local" so doesn't seem to be compatible with quantum field theory.

So my point was that if you don't like multiple radioactive atoms "choreographing" between themselves about when to decay so that their random decay events average out to a nice exponential curve, you shouldn't like these particles "choreographing" with the ones before and after so that their random positions on the screen average out to form interference fringes.
jimbob wrote:
Fri Feb 04, 2022 10:48 am
Don't delocalised electron clouds, in your "favourite" substance, graphene, for example show that it's not just us that can't tell where the electron is and its momentum, but the electron itself or the universe itself doesn't either?
Not just graphene but any periodic arrangement of atoms i.e. a silicon or germanium crystal. Much more natural to treat the electrons in terms of their momenta rather than their positions; they form waves which slot into the periodic potential of the crystal ("Bloch states"). Doesn't mean you can't then inject electrons at a particular position and watch them drift through the material.

** ETA but one way to model the absorption of a photon is to consider an oscillating electric field as a perturbation on the states in the crystal i.e. as a wave.
having that swing is a necessary but not sufficient condition for it meaning a thing
@shpalman@mastodon.me.uk

User avatar
dyqik
Light of Blast
Posts: 6430
Joined: Wed Sep 25, 2019 4:19 pm
Location: A rock in the middle of the Pacific
Contact:

Re: Super determinism

Post by dyqik » Fri Feb 04, 2022 2:25 pm

shpalman wrote:
Fri Feb 04, 2022 10:34 am
dyqik wrote:
Thu Feb 03, 2022 2:00 pm
shpalman wrote:
Thu Feb 03, 2022 9:19 am
We've already ruled out certain classes of Hidden Variable theory, but those relate to the particle secretly "knowing" what it's going to do in a way which isn't manifest in its own wavefunction, not the wavefunction of the rest of the universe (which, if you're deterministic, "knows" everything).
I'm not sure that this is even as simple as you state here. Most of the universe is not, and never has been, causally connected to our observable universe, so the definition of "rest of universe" is complicated. It differs for a quantum state of a particle localized in M87 vs the quantum state of a particle localized here.

General relativity is even more complicated to make standard quantum mechanics work with than special relativity, and probably needs quantum theory to be altered, even before you look at the measurement problem.
What you mean I didn't just manage to unify quantum mechanics and gravity just now in a short forum post.
Mostly I mean that the view that the non-determinacy in quantum measurement goes away if you model the rest of the universe is either wrong, or is useless as a way of recovering determinacy.

IvanV
After Pie
Posts: 1731
Joined: Mon May 17, 2021 11:12 am

Re: Super determinism

Post by IvanV » Fri Feb 04, 2022 5:42 pm

shpalman wrote:
Fri Feb 04, 2022 10:33 am
IvanV wrote:
Fri Feb 04, 2022 9:45 am
Particle decay does a good job of appearing to be perfectly random. If it wasn't actually random, but a deterministic system creating the appearance of randomness, then there would have to be some kind of organisation between the individual particles, rather than the particles behaving independently, so that they could choreograph that appearance of randomness so perfectly. The whole lot of them would have to be entangled over a sufficiently broad area. Mr Occam wouldn't like that kind of an explanation for it.

Perhaps you can explain what I'm missing.
Free neutrons aren't stable; they decay to protons with a half life of about 15 minutes. Free protons are stable. But a deuteron (bound state of a proton and a neutron, the nucleus of deuterium) is indefinitely stable. So there's obviously enough choreography between the neutron and the proton that the neutron doesn't decay. When you get up to isotopes like carbon-11, nitrogen-13, oxygen-15, or sodium-22 for example, protons decays to neutrons in those.

Going back to the double-slit experiment, done with one particle at a time, each particle gives a single spot on the detector in a "random" position but when you average over lots of particles the inteference fringes are visible. How does each particle behave randomly but still manage to "choreograph" with the ones before it and the ones after it in order that the average gives the right answer?
If free neutrons behave in a random fashion with respect to when they decay, it is straightforward for a cloud of them, dispersed over a large expanse of space, to exhibit a Laplace distribution with half life of 15 minutes in their decays.

It is difficult, at least for me, to imagine a deterministic behaviour for each neutron that enables all those individual neutrons to time their decay deterministically, such that the dispersed cloud mimics a Laplace distribution with half life of 15 minutes.

I find it is not unreasonable to expect the particles within a nucleus to interact, so that the proton and neutron change their decay characteristics. At least we have got used to that idea, because we need something like that to explain the behaviour of nuclei. What is rather different is for the many trillions of say, some Uranium 235 nuclei, dispersed at 20ppm in some large rock, to interact. At that point it starts to become as unlikely as Schrodinger's tardigrade.

It is also entirely straightforward to give particles going through a slit a random component to their behaviour such that they exhibit a particular distribution on the detector screen. What's difficult, for me, is to imagine a deterministic behaviour so that they demonstrate that distribution.

That's what I'm trying to say. Maybe it's illiterate. Quantum mechanics is difficult, and I haven't even studied a physics degree.

User avatar
shpalman
Princess POW
Posts: 7556
Joined: Mon Nov 11, 2019 12:53 pm
Location: One step beyond
Contact:

Re: Super determinism

Post by shpalman » Fri Feb 04, 2022 9:25 pm

I mean, it's difficult for me to imagine a random behaviour for each neutron that enables all those individual neutrons to average out to the right statistical distribution, or for the particles going through a double slit to all go in random directions but still average out to interference fringes.

But then I don't think anyone knows the answer to this, or even if it's a question which makes sense to ask.
having that swing is a necessary but not sufficient condition for it meaning a thing
@shpalman@mastodon.me.uk

User avatar
dyqik
Light of Blast
Posts: 6430
Joined: Wed Sep 25, 2019 4:19 pm
Location: A rock in the middle of the Pacific
Contact:

Re: Super determinism

Post by dyqik » Fri Feb 04, 2022 9:28 pm

The reason that free neutrons decay while bound neutrons (in simple atoms) don't is that bound neutrons are stuck in a hierarchical quantum system that makes the decay forbidden by various quantum selection rules and Pauli exclusion. In particular for He4 (in the shell model of the atomic nucleus), the two lowest energy proton states are already filled with two protons (1 spin up, 1 spin down), so that for a neutron to decay to a proton, the resulting proton would have occupy a higher energy level than the initial neutron.

User avatar
dyqik
Light of Blast
Posts: 6430
Joined: Wed Sep 25, 2019 4:19 pm
Location: A rock in the middle of the Pacific
Contact:

Re: Super determinism

Post by dyqik » Fri Feb 04, 2022 9:29 pm

shpalman wrote:
Fri Feb 04, 2022 9:25 pm
I mean, it's difficult for me to imagine a random behaviour for each neutron that enables all those individual neutrons to average out to the right statistical distribution, or for the particles going through a double slit to all go in random directions but still average out to interference fringes.
There's literally nothing to imagine - it's just a random process with no internal workings. Demanding to be able to imagine it is assuming it is deterministic.

User avatar
jimbob
Light of Blast
Posts: 4512
Joined: Mon Nov 11, 2019 4:04 pm
Location: High Peak/Manchester

Re: Super determinism

Post by jimbob » Sat Feb 05, 2022 10:06 am

dyqik wrote:
Fri Feb 04, 2022 9:29 pm
shpalman wrote:
Fri Feb 04, 2022 9:25 pm
I mean, it's difficult for me to imagine a random behaviour for each neutron that enables all those individual neutrons to average out to the right statistical distribution, or for the particles going through a double slit to all go in random directions but still average out to interference fringes.
There's literally nothing to imagine - it's just a random process with no internal workings. Demanding to be able to imagine it is assuming it is deterministic.
Indeed.

How does a fair die* end up approaching a uniform distribution without knowing previous history


Pretending that it's random
Have you considered stupidity as an explanation

IvanV
After Pie
Posts: 1731
Joined: Mon May 17, 2021 11:12 am

Re: Super determinism

Post by IvanV » Sat Feb 05, 2022 2:51 pm

dyqik wrote:
Fri Feb 04, 2022 9:29 pm
shpalman wrote:
Fri Feb 04, 2022 9:25 pm
I mean, it's difficult for me to imagine a random behaviour for each neutron that enables all those individual neutrons to average out to the right statistical distribution, or for the particles going through a double slit to all go in random directions but still average out to interference fringes.
There's literally nothing to imagine - it's just a random process with no internal workings. Demanding to be able to imagine it is assuming it is deterministic.
Exactly. Thanks. It's nice to know I'm not alone.

User avatar
shpalman
Princess POW
Posts: 7556
Joined: Mon Nov 11, 2019 12:53 pm
Location: One step beyond
Contact:

Re: Super determinism

Post by shpalman » Mon Feb 07, 2022 10:01 am

There' s a difference in character between the classical unpredictability of a fair die, where the randomness comes from us not knowing the initial conditions or the dynamics to sufficient precision. In principle it's completely deterministic but we don't know enough. The quantum stuff, as Dyqik said, just doesn't have that internal structure. The evolution of the wavefunction is completely deterministic but won't tell you which specific state your next measurement is going to collapse to; we can either consider this a sign that quantum mechanics is incomplete or that we've failed to take into account the quantum mechanics of our whole measurement system.

Of course we know quantum mechanics isn't complete: it doesn't have gravity in it, for one thing. Would the screen with the two slits in it be able to "feel" the mass of the particle going through one slit or the other, for example, once the particle got heavy enough?

I'm not sure I particularly like Super Determinism, though. Think I prefer a transactional interpretation.
having that swing is a necessary but not sufficient condition for it meaning a thing
@shpalman@mastodon.me.uk

User avatar
jimbob
Light of Blast
Posts: 4512
Joined: Mon Nov 11, 2019 4:04 pm
Location: High Peak/Manchester

Re: Super determinism

Post by jimbob » Mon Feb 07, 2022 1:52 pm

shpalman wrote:
Mon Feb 07, 2022 10:01 am
There' s a difference in character between the classical unpredictability of a fair die, where the randomness comes from us not knowing the initial conditions or the dynamics to sufficient precision. In principle it's completely deterministic but we don't know enough. The quantum stuff, as Dyqik said, just doesn't have that internal structure. The evolution of the wavefunction is completely deterministic but won't tell you which specific state your next measurement is going to collapse to; we can either consider this a sign that quantum mechanics is incomplete or that we've failed to take into account the quantum mechanics of our whole measurement system.

Of course we know quantum mechanics isn't complete: it doesn't have gravity in it, for one thing. Would the screen with the two slits in it be able to "feel" the mass of the particle going through one slit or the other, for example, once the particle got heavy enough?

I'm not sure I particularly like Super Determinism, though. Think I prefer a transactional interpretation.

That's why I said "pretending it's random"

I am unsure how chaotic systems interact with quantum events. Say the momentum change imparted or not by an alpha particle.
Have you considered stupidity as an explanation

IvanV
After Pie
Posts: 1731
Joined: Mon May 17, 2021 11:12 am

Re: Super determinism

Post by IvanV » Mon Feb 07, 2022 2:40 pm

shpalman wrote:
Mon Feb 07, 2022 10:01 am
There' s a difference in character between the classical unpredictability of a fair die, where the randomness comes from us not knowing the initial conditions or the dynamics to sufficient precision. In principle it's completely deterministic but we don't know enough. The quantum stuff, as Dyqik said, just doesn't have that internal structure. The evolution of the wavefunction is completely deterministic but won't tell you which specific state your next measurement is going to collapse to; we can either consider this a sign that quantum mechanics is incomplete or that we've failed to take into account the quantum mechanics of our whole measurement system.
It is a very good point that the appearance of randomness can result from the magnification of errors in a deterministic process which we haven't measured very well. Or chaotic processes, if you like, chaos being the kind of process where small differences are magnified to very different outcomes. So in principle there could actually be a deterministic but chaotic machine inside something like a neutron creating the appearance of randomness over when it decays.

But also, maybe that's just a quibble. Perhaps that's all randomness ever is - chaotic deterministic machines creating the appearance of randomness. Does that mean that randomness is vacuous, and nothing is ever random? To me, if it has the outcome effect of randomness, that's a random process, even if it has a deterministic machine inside it that made that randomness.

Another philosophical issue is the interaction of Heisenberg and chaos. Chaos so magniifies errors the outcome can depend upon distinctions of such small magnitude that Heisenberg tells us we can't know them. There are issues of around that Heisenberg doesn't tell us that the differences don't exist, just that we can't know them. But isn't that the point? If we can't know them, we can't control them, and so the outcome it outside of our control.

I think "deterministic" ceases to have the meaning we expect of it, if we say that the random processes created by internal deterministic chaotic machines are deterministic, not random.

As for your wave function collapse. Perhaps it doesn't matter if it is genuinely a random process out of nature, or there is some internal deterministic machine creating the appearance of randomness that we can't detect.

User avatar
dyqik
Light of Blast
Posts: 6430
Joined: Wed Sep 25, 2019 4:19 pm
Location: A rock in the middle of the Pacific
Contact:

Re: Super determinism

Post by dyqik » Mon Feb 07, 2022 3:50 pm

IvanV wrote:
Mon Feb 07, 2022 2:40 pm
shpalman wrote:
Mon Feb 07, 2022 10:01 am
There' s a difference in character between the classical unpredictability of a fair die, where the randomness comes from us not knowing the initial conditions or the dynamics to sufficient precision. In principle it's completely deterministic but we don't know enough. The quantum stuff, as Dyqik said, just doesn't have that internal structure. The evolution of the wavefunction is completely deterministic but won't tell you which specific state your next measurement is going to collapse to; we can either consider this a sign that quantum mechanics is incomplete or that we've failed to take into account the quantum mechanics of our whole measurement system.
It is a very good point that the appearance of randomness can result from the magnification of errors in a deterministic process which we haven't measured very well. Or chaotic processes, if you like, chaos being the kind of process where small differences are magnified to very different outcomes. So in principle there could actually be a deterministic but chaotic machine inside something like a neutron creating the appearance of randomness over when it decays.
In principle, there could. But something "inside a neutron" would be a local hidden variable, and that's been experimentally proven to not be the case for most versions by tests of Bell's inequality. Superdeterminism is an attempt to avoid Bell's theorem and its experimental tests.

User avatar
jimbob
Light of Blast
Posts: 4512
Joined: Mon Nov 11, 2019 4:04 pm
Location: High Peak/Manchester

Re: Super determinism

Post by jimbob » Mon Feb 07, 2022 7:05 pm

dyqik wrote:
Mon Feb 07, 2022 3:50 pm
IvanV wrote:
Mon Feb 07, 2022 2:40 pm
shpalman wrote:
Mon Feb 07, 2022 10:01 am
There' s a difference in character between the classical unpredictability of a fair die, where the randomness comes from us not knowing the initial conditions or the dynamics to sufficient precision. In principle it's completely deterministic but we don't know enough. The quantum stuff, as Dyqik said, just doesn't have that internal structure. The evolution of the wavefunction is completely deterministic but won't tell you which specific state your next measurement is going to collapse to; we can either consider this a sign that quantum mechanics is incomplete or that we've failed to take into account the quantum mechanics of our whole measurement system.
It is a very good point that the appearance of randomness can result from the magnification of errors in a deterministic process which we haven't measured very well. Or chaotic processes, if you like, chaos being the kind of process where small differences are magnified to very different outcomes. So in principle there could actually be a deterministic but chaotic machine inside something like a neutron creating the appearance of randomness over when it decays.
In principle, there could. But something "inside a neutron" would be a local hidden variable, and that's been experimentally proven to not be the case for most versions by tests of Bell's inequality. Superdeterminism is an attempt to avoid Bell's theorem and its experimental tests.
And I still don't see how you get any non-periodic structure from initial conditions for the big bang - or indeed any other starting conditions for the universe.
Have you considered stupidity as an explanation

Post Reply