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**New Theories / Re: Could quantum mechanics be wrong?**

« **on:**08/09/2024 02:49:37 »

Hi.

Probably not in an easy way for human beings to understand.

It probably is possible to use QM and apply a suitable interpretation of probabilities or the frequency of detection of photons to re-create the usual gross-scale classical radio wave propagation results - but this would be complicated.

At the fundamental level, in most QM models there aren't any "radio waves". So the problem starts with the way the question was phrased.

The name "radio wave" that you are using in the question describes a phenomena that we (human beings) have come to ascribe some meaning to. This thing, "a radio wave", is an essentially classical physical phenomena.

We imagine a radio wave as a ... (you know) ..... spread out and continuous wave thing. We expect to be able to measure an Electric and a Magnetic field and a radio wave will be a suitable oscillation in these fields. There are many versions of Quantum Mechanics but most of them don't have that sort of thing as their subjects or objects of interest. The simplest QM models consider all objects as if they are particles. For example, we might consider a particle of light, a photon, as a suitable QM object but we do not consider an e-m wave as a suitable QM object. QM objects just happen to have a wave function associated to them BUT they are essentially discrete particles and would always be detected as a discrete particle.

More advanced QM theories, such as the mainstream versions of QFT, will consider the most fundamental objects to be fields. For example, there will be a photon field that exists everywhere in space. The thing we call a photon would not be treated as a fundamental QM object, it is just how we may interpret a certain oscillation in that underlying photon field at some place. So, in QFT, there is a photon field but there is NOT any fundamental Electric field or Magnetic field. These things, the electric and magnetic fields are just gross-scale fields that can emerge from the more fundamental fields of the particles in the standard model of particle physics. QFT doesn't aim to deal with oscillations in the Electric and Magnetic fields, it only deals with the fundamental particle fields. You need to add a layer of interpretation on to the top to translate what happens in these fundamental particle fields into something that can be observed in the gross-scale Electric and Magnetic fields. That can be done in many versions of QFT but is rarely simple.

When you are asking about "a radio wave", you have moved attention to something in terms of the ordinary (or gross-scale) Electric and Magnetic fields and not on any fundamental object (a photon in simple QM, or the photon field in QFT). So the question cannot be answered without translating the results of QM back into something classical involving the Electric and Magnetic fields. One of the simplest or most naive ways of making this translation is to just analyse the probablities or frequencies with which a QM object would be found at some place and time. So, we might imagine that an e-m wave is a collection of many photons or that an experiment involving one photon has been done many times and the e-m wave we observe is the combined average of all of these.

Example: If you could fire just one photon through the usual double-slit experiment apparatus, then you probably won't get an interference pattern on the screen at the end. Instead we think you'll get just one spot to glow on the screen. However, if we repeat the experiment many, many times then we expect to see that the places where the screen glows and how often that bit of the screen glows will correspond to the usual interference pattern for a classical wave being put through that apparatus. So, one individual photon does NOT behave like an e-m wave - but a thousand or a million of them would seem to reproduce classical radio wave-like patterns and behaviour.

https://sciencedemonstrations.fas.harvard.edu/presentations/single-photon-interference

So, the important point is simply that "a radio wave" isn't the normal subject for any QM model. It demands some form of interpretation to put the results predicted by any QM model back into terms which would make sense when you consider "a radio wave".

If we wished to be controversial we would say "there are NO radio waves... just QM objects that get detected at certain times and places. On a gross scale, that looks like a radio wave is there". ... However... I'm not that controversial or convinced that a simple QM model is some ultimate truth.... there are many versions of QM, all have some use and classical e-m theory is also extremely useful.

Another minor note: Your (Hamdani) extracts produced by Gemini seem to be blending many different versions of Quantum Mechanics. For example, QFT is a specialised theory and there are still about 3 versions or flavours of QFT that are in current use. I don't think Geminii is reliably identifying where things can and cannot be combined. For example, the simplest QM models are not like QFT. They will involve the original Schrodinger equation, which is shown here:

That has a mass term, m, in the Hamiltonian for the QM object under consideration (it's in the square bracket, h squared over 2 m). This means it's actually useless for photons which should have 0 rest mass. None the less, we (physicists) do generalise a lot of results from such a QM theory for massive particles to massless particles like photons. For example, the Youngs double slit experiment can be modelled for electrons or even bigger particles like carbon bucky-balls. We can (and have) then done experiments with these things and obtained a good match with the predictions from the simple QM model. It is natural to assume a similar thing for photons, even though the zero mass term would technically make the simple QM model invalid. If you read what I've said (above) about firing single photons then you'll hopefully notice that I've got phrases like "we think".

I believe that how you reconcile a classical radio wave with a suitable QM object ("a photon") is subject to a lot of interpretation.

[Disclaimer: I'M NOT AN EXPERT. ]

Best Wishes.

Can quantum mechanics explain the generation, propagation, and reception of radio waves?

**Short Answer:**Probably not in an easy way for human beings to understand.

It probably is possible to use QM and apply a suitable interpretation of probabilities or the frequency of detection of photons to re-create the usual gross-scale classical radio wave propagation results - but this would be complicated.

At the fundamental level, in most QM models there aren't any "radio waves". So the problem starts with the way the question was phrased.

**Medium detail / further discussion:**The name "radio wave" that you are using in the question describes a phenomena that we (human beings) have come to ascribe some meaning to. This thing, "a radio wave", is an essentially classical physical phenomena.

We imagine a radio wave as a ... (you know) ..... spread out and continuous wave thing. We expect to be able to measure an Electric and a Magnetic field and a radio wave will be a suitable oscillation in these fields. There are many versions of Quantum Mechanics but most of them don't have that sort of thing as their subjects or objects of interest. The simplest QM models consider all objects as if they are particles. For example, we might consider a particle of light, a photon, as a suitable QM object but we do not consider an e-m wave as a suitable QM object. QM objects just happen to have a wave function associated to them BUT they are essentially discrete particles and would always be detected as a discrete particle.

More advanced QM theories, such as the mainstream versions of QFT, will consider the most fundamental objects to be fields. For example, there will be a photon field that exists everywhere in space. The thing we call a photon would not be treated as a fundamental QM object, it is just how we may interpret a certain oscillation in that underlying photon field at some place. So, in QFT, there is a photon field but there is NOT any fundamental Electric field or Magnetic field. These things, the electric and magnetic fields are just gross-scale fields that can emerge from the more fundamental fields of the particles in the standard model of particle physics. QFT doesn't aim to deal with oscillations in the Electric and Magnetic fields, it only deals with the fundamental particle fields. You need to add a layer of interpretation on to the top to translate what happens in these fundamental particle fields into something that can be observed in the gross-scale Electric and Magnetic fields. That can be done in many versions of QFT but is rarely simple.

When you are asking about "a radio wave", you have moved attention to something in terms of the ordinary (or gross-scale) Electric and Magnetic fields and not on any fundamental object (a photon in simple QM, or the photon field in QFT). So the question cannot be answered without translating the results of QM back into something classical involving the Electric and Magnetic fields. One of the simplest or most naive ways of making this translation is to just analyse the probablities or frequencies with which a QM object would be found at some place and time. So, we might imagine that an e-m wave is a collection of many photons or that an experiment involving one photon has been done many times and the e-m wave we observe is the combined average of all of these.

Example: If you could fire just one photon through the usual double-slit experiment apparatus, then you probably won't get an interference pattern on the screen at the end. Instead we think you'll get just one spot to glow on the screen. However, if we repeat the experiment many, many times then we expect to see that the places where the screen glows and how often that bit of the screen glows will correspond to the usual interference pattern for a classical wave being put through that apparatus. So, one individual photon does NOT behave like an e-m wave - but a thousand or a million of them would seem to reproduce classical radio wave-like patterns and behaviour.

**NOTE:**I'm really not convinced anyone has actually done a genuine version of Young's double slit experiment where only a single photon is fired with a clear interval of time before the next is fired. However, this demonstration gets close and claims to be using such a thin and dim stream of light that only "a few" photons per second will be produced.https://sciencedemonstrations.fas.harvard.edu/presentations/single-photon-interference

So, the important point is simply that "a radio wave" isn't the normal subject for any QM model. It demands some form of interpretation to put the results predicted by any QM model back into terms which would make sense when you consider "a radio wave".

If we wished to be controversial we would say "there are NO radio waves... just QM objects that get detected at certain times and places. On a gross scale, that looks like a radio wave is there". ... However... I'm not that controversial or convinced that a simple QM model is some ultimate truth.... there are many versions of QM, all have some use and classical e-m theory is also extremely useful.

Another minor note: Your (Hamdani) extracts produced by Gemini seem to be blending many different versions of Quantum Mechanics. For example, QFT is a specialised theory and there are still about 3 versions or flavours of QFT that are in current use. I don't think Geminii is reliably identifying where things can and cannot be combined. For example, the simplest QM models are not like QFT. They will involve the original Schrodinger equation, which is shown here:

That has a mass term, m, in the Hamiltonian for the QM object under consideration (it's in the square bracket, h squared over 2 m). This means it's actually useless for photons which should have 0 rest mass. None the less, we (physicists) do generalise a lot of results from such a QM theory for massive particles to massless particles like photons. For example, the Youngs double slit experiment can be modelled for electrons or even bigger particles like carbon bucky-balls. We can (and have) then done experiments with these things and obtained a good match with the predictions from the simple QM model. It is natural to assume a similar thing for photons, even though the zero mass term would technically make the simple QM model invalid. If you read what I've said (above) about firing single photons then you'll hopefully notice that I've got phrases like "we think".

I believe that how you reconcile a classical radio wave with a suitable QM object ("a photon") is subject to a lot of interpretation.

[Disclaimer: I'M NOT AN EXPERT. ]

Best Wishes.

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