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I wouldn't say Einstein was wrong. It is a sad story that he never got to see the work of Nobel laureate Julian Schwinger on Quantum Field Theory, or the contri

I wouldn't say Einstein was wrong. It is a sad story that he never got to see the work of Nobel laureate Julian Schwinger on Quantum Field Theory, or the contributions of other Nobel laureates like Frank Wilczek. Switching from a particle-centric theory (like Quantum Mechanics) to a field-centric theory makes all the QM paradoxes disappear, and problems like locality, the double-slit experiment, etc., become trivial. What we have been calling particles are instead oscillators in fields. The Schrödinger equation is a wave function, but Quantum Mechanics has been using it to represent a probability distribution instead of an actual wave. Why is that? Because of the focus on particles. If everything has to be a particle, then of course we have to use a wave function as a probability distribution. But why force that view? We know how to describe fields since the days of Faraday and Maxwell, yet after Copenhagen all we want to do is to force wave-describing partial differential equations into a probabilistic model full of paradoxes.

petmon 4y ago
The case for particles is quantization. We've never seen half a photon or half an electron. This dates back to the ultraviolet catastrophe. If it was all about waves that would be easy; we reluctantly acknowledge particles because Nature has forced us to.
- timberfox 4y ago
  Quanta is fundamental to Quantum Field Theory so it can't be the deviding factor. I would say we are biased to think in terms of particles because our brains and senses have evolved to perceive macro objects as having a precise location and definite boundaries, thus we have a tendency to project that macro structure onto everything we want to describe.
  - Jensson 4y ago
    But they still aren't waves. Waves can be split, quantum particlewaves can't. This is a fundamental difference and makes them neither waves nor particles.
    - timberfox 4y ago
      What wave are you referring to?
      - evanb 4y ago
        Not OP but (classical) electromagnetic waves, water waves, and sound waves can all be split arbitrarily.
        cycomanic 4y ago
        Not all waves can be split, e.g. Solitons which are named because of their particle like nature and can be observed in optics, water chains of oscillators and more. I think that is the crux of the issue, we have waves with a discrete energy, we can call them particles but they are very different from the traditional image that people have of what a particle is.
        Jensson 4y ago
        You can easily split solitons in water, just cut it in the middle and both sides will continue to live on as the water displacement field is still there. On the other hand, try grab a part of an electron cloud around an atom and you will either get the entire electron or you will grab nothing. No matter what you do you can't separate one part of the cloud from the other, they are always connected. Trying to grab the electron will either remove all of the wave parts outside, or remove all of the wave part you try to grab. There is no classical system that behaves like this.
      - Jensson 4y ago
        It is equally wrong to view them as classical particles as it is to view them as classical waves. Classical particles with a probability wave is more accurate than both of those, but still not fully accurate. However I don't think there is any better likeness than that, to explain better you'd need to teach the math and equations behind quantum mechanics which usually takes years.
- selimthegrim 4y ago
  The quantum Hall effect would like a word
solarengineer 4y ago
Goodness!! Thanks for articulating this so well!!
bluepnume 4y ago
I take it you're a MWI fan then? Isn't the answer for why we "force wave-describing partial differential equations into a probabilistic model" because in our reality, when we look at an electron we observe something that looks like a particle and not a wave?
- sterlind 4y ago
  not a physicist, but afaik MWI doesn't work like that. iirc, particles are actually excitations in a quantum field. the more particle-y an electron looks - the closer you bound its position - the more waves are needed to constructively/destructively interfere to make a peak there. it's like a Fourier transform - if you want a perfect square wave you need infinite sine waves. in this analogy that's momentum space expanding out. also, like, you're not really seeing individual electrons. you're seeing macroscopic phenomena, like your sensor or photomultiplier tube or whatever. you're seeing the interaction, not the particle. understanding that as your lab equipment, retina and brain entering the state space caused by resolving a wave to a spike makes more sense to me than some decoherence mechanism.
- timberfox 4y ago
  I'm not a fan of the Many-Worlds Interpretation :-) As for the electron, it is an oscillator described by a wave function, quantized, without locality. Here is an image of the wave function interpreted as a probability density: https://en.wikipedia.org/wiki/Electron#/media/File:Hydrogen_Density_Plots.png https://en.wikipedia.org/wiki/Electron#/media/File:Hydrogen_... The Quantum Mechanics interpretation is that the electron is a particle in an indeterminate location and the plot describes the probability of where the electron can be located. The Quantum Field Theory interpretation is that what we see is a field in an excited state, quantized. By looking at those plots, we can see a quantized field vibrating. If we send it through a double slit, it will behave like a wave. If instead we think about it as a single, indivisible particle, then we need to explain how it passes through two different slits at the same time. Thinking about it as a quantized oscillator disolves the paradox.
  - bluepnume 4y ago
    Makes sense -- but if you're saying "the electron travels through both slits at the same time because it is a wave", then why can't we detect that wave simultaneously at both slits? At that point of measurement/detection we HAVE to start talking about probabilities, not just waves, right?
TheOtherHobbes 4y ago
The designers of the LHC will be very surprised to learn their machine is just twisting fields together. You can easily count individual photons, electrons, etc in an undergrad physics lab. How do you think that's possible with fields alone? There's an interest in particles because there is no way to measure fields directly and the output of QFT is a set of particle-like probabilities. This is not a trivial problem, QFT is not a trivial solution to it, and the paradoxes really haven't gone away.
- timberfox 4y ago
  What most physicists refer to as "particle" is very different from what lay people understand by that term. If you ask physicists at the LHC about particles, they will explain what I've already mentioned, because what I'm saying is far from being revolutionary. You can count individual quanta of any kind (photons, electrons, etc.), and you can measure their quantum collapse. But that does not mean they are localized "particles" the way Dirac liked to think about them.
  - phkahler 4y ago
    >> and you can measure their quantum collapse. No. There is no way to discern a collapsed wave function from a non collapsed one, if that's what you mean.
    - Jensson 4y ago
      Of course you can do that, if we couldn't detect state collapses then they wouldn't be a staple of quantum mechanics. If you measure a rotating wave function over and over then it wont rotate since it will collapse into the same state again, while if you let it be it can rotate into another state giving you another measurement result. This works since rotations aren't linear, small rotations are quadratic and hence will almost always result in the original state. You can also use this technique to rotate a state by making many measurements slowly changing the axis, so each measurement results in a small rotation. Edit: But you are right that we can't see the history of state collapses, but they are definitely required for our current theories to work as you get the wrong experimental results without them in the theory.
OscarCunningham 4y ago
But quantum field theory doesn't replace probability distributions on particles with fields; it replaces them with probability distributions on fields.
quantum_state 4y ago
Would like to follow up on your assertion: “Switching from a particle-centric theory (like Quantum Mechanics) to a field-centric theory makes all the QM paradoxes disappear, and problems like locality, the double-slit experiment, etc., become trivial.“ I feel the same way. Would you know of any references that described the actual experiments seemingly revealing the paradoxes from quantum field theory perspective? Would appreciate it if you could share the references. Thanks!
- Agamus 4y ago
  I too would like to see this. This strange work tracks ontological implications of QFT, and extends into metaethics: http://www.katabane.com/mt/ontology.html http://www.katabane.com/mt/ontology.html

petmon 4y ago

The case for particles is quantization. We've never seen half a photon or half an electron. This dates back to the ultraviolet catastrophe. If it was all about waves that would be easy; we reluctantly acknowledge particles because Nature has forced us to.

timberfox 4y ago
Quanta is fundamental to Quantum Field Theory so it can't be the deviding factor. I would say we are biased to think in terms of particles because our brains and senses have evolved to perceive macro objects as having a precise location and definite boundaries, thus we have a tendency to project that macro structure onto everything we want to describe.
- Jensson 4y ago
  But they still aren't waves. Waves can be split, quantum particlewaves can't. This is a fundamental difference and makes them neither waves nor particles.
  - timberfox 4y ago
    What wave are you referring to?
    - evanb 4y ago
      Not OP but (classical) electromagnetic waves, water waves, and sound waves can all be split arbitrarily.
      - cycomanic 4y ago
        Not all waves can be split, e.g. Solitons which are named because of their particle like nature and can be observed in optics, water chains of oscillators and more. I think that is the crux of the issue, we have waves with a discrete energy, we can call them particles but they are very different from the traditional image that people have of what a particle is.
        Jensson 4y ago
        You can easily split solitons in water, just cut it in the middle and both sides will continue to live on as the water displacement field is still there. On the other hand, try grab a part of an electron cloud around an atom and you will either get the entire electron or you will grab nothing. No matter what you do you can't separate one part of the cloud from the other, they are always connected. Trying to grab the electron will either remove all of the wave parts outside, or remove all of the wave part you try to grab. There is no classical system that behaves like this.
    - Jensson 4y ago
      It is equally wrong to view them as classical particles as it is to view them as classical waves. Classical particles with a probability wave is more accurate than both of those, but still not fully accurate. However I don't think there is any better likeness than that, to explain better you'd need to teach the math and equations behind quantum mechanics which usually takes years.
selimthegrim 4y ago
The quantum Hall effect would like a word

solarengineer 4y ago

Goodness!! Thanks for articulating this so well!!

bluepnume 4y ago

I take it you're a MWI fan then? Isn't the answer for why we "force wave-describing partial differential equations into a probabilistic model" because in our reality, when we look at an electron we observe something that looks like a particle and not a wave?

sterlind 4y ago
not a physicist, but afaik MWI doesn't work like that. iirc, particles are actually excitations in a quantum field. the more particle-y an electron looks - the closer you bound its position - the more waves are needed to constructively/destructively interfere to make a peak there. it's like a Fourier transform - if you want a perfect square wave you need infinite sine waves. in this analogy that's momentum space expanding out. also, like, you're not really seeing individual electrons. you're seeing macroscopic phenomena, like your sensor or photomultiplier tube or whatever. you're seeing the interaction, not the particle. understanding that as your lab equipment, retina and brain entering the state space caused by resolving a wave to a spike makes more sense to me than some decoherence mechanism.
timberfox 4y ago
I'm not a fan of the Many-Worlds Interpretation :-) As for the electron, it is an oscillator described by a wave function, quantized, without locality. Here is an image of the wave function interpreted as a probability density: https://en.wikipedia.org/wiki/Electron#/media/File:Hydrogen_Density_Plots.png https://en.wikipedia.org/wiki/Electron#/media/File:Hydrogen_... The Quantum Mechanics interpretation is that the electron is a particle in an indeterminate location and the plot describes the probability of where the electron can be located. The Quantum Field Theory interpretation is that what we see is a field in an excited state, quantized. By looking at those plots, we can see a quantized field vibrating. If we send it through a double slit, it will behave like a wave. If instead we think about it as a single, indivisible particle, then we need to explain how it passes through two different slits at the same time. Thinking about it as a quantized oscillator disolves the paradox.
- bluepnume 4y ago
  Makes sense -- but if you're saying "the electron travels through both slits at the same time because it is a wave", then why can't we detect that wave simultaneously at both slits? At that point of measurement/detection we HAVE to start talking about probabilities, not just waves, right?

TheOtherHobbes 4y ago

The designers of the LHC will be very surprised to learn their machine is just twisting fields together. You can easily count individual photons, electrons, etc in an undergrad physics lab. How do you think that's possible with fields alone? There's an interest in particles because there is no way to measure fields directly and the output of QFT is a set of particle-like probabilities. This is not a trivial problem, QFT is not a trivial solution to it, and the paradoxes really haven't gone away.

timberfox 4y ago
What most physicists refer to as "particle" is very different from what lay people understand by that term. If you ask physicists at the LHC about particles, they will explain what I've already mentioned, because what I'm saying is far from being revolutionary. You can count individual quanta of any kind (photons, electrons, etc.), and you can measure their quantum collapse. But that does not mean they are localized "particles" the way Dirac liked to think about them.
- phkahler 4y ago
  >> and you can measure their quantum collapse. No. There is no way to discern a collapsed wave function from a non collapsed one, if that's what you mean.
  - Jensson 4y ago
    Of course you can do that, if we couldn't detect state collapses then they wouldn't be a staple of quantum mechanics. If you measure a rotating wave function over and over then it wont rotate since it will collapse into the same state again, while if you let it be it can rotate into another state giving you another measurement result. This works since rotations aren't linear, small rotations are quadratic and hence will almost always result in the original state. You can also use this technique to rotate a state by making many measurements slowly changing the axis, so each measurement results in a small rotation. Edit: But you are right that we can't see the history of state collapses, but they are definitely required for our current theories to work as you get the wrong experimental results without them in the theory.

OscarCunningham 4y ago

But quantum field theory doesn't replace probability distributions on particles with fields; it replaces them with probability distributions on fields.

quantum_state 4y ago

Would like to follow up on your assertion: “Switching from a particle-centric theory (like Quantum Mechanics) to a field-centric theory makes all the QM paradoxes disappear, and problems like locality, the double-slit experiment, etc., become trivial.“ I feel the same way. Would you know of any references that described the actual experiments seemingly revealing the paradoxes from quantum field theory perspective? Would appreciate it if you could share the references. Thanks!

Agamus 4y ago
I too would like to see this. This strange work tracks ontological implications of QFT, and extends into metaethics: http://www.katabane.com/mt/ontology.html http://www.katabane.com/mt/ontology.html