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Old 03-04-2020, 11:01 PM
bgilbert (Barry gilbert)
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Einstein's Photo electric Effect in your radio receiver

. The output of your radio is independent of the input intensity, but can only respond to one discrete energy level(frequency) at a time.

. If you replaced the variable band pass filter in your radio, with a high pass filter, it would behave exactly like the Photoelectric Effect for a chosen metal. Different metals would need different cutoff frequency filters.

. Barry
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Old 07-04-2020, 09:37 AM
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Shiraz (Ray)
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not my radio Barry.

RF photons are about 8-9 orders of magnitude less energetic than visible ones and are completely undetectable as individual entities....as far as I know, individual photons are detectable in the microwave region (just), but not at longer wavelengths.

Seems to me that it makes no sense to try to use photon concepts when dealing with radio waves. Just as it makes no sense to use RF design techniques when dealing with gamma ray photons. Horses for courses.

Cheers Ray

Last edited by Shiraz; 07-04-2020 at 10:40 PM.
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Old 10-04-2020, 03:12 AM
bgilbert (Barry gilbert)
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. G'day Ray

. With respect, I think you have missed the point, I’m trying to demonstrate a principle that can be adapted to any frequency. The “Photo Electric Effect” is considered a crucial stumbling block for classical theory, I’m basically proposing that metals could have the equivalent of a “High Pass Filter”(HPF) in their surface. The simplest HPF is a hollow open ended cylinder.
. How do you explain the existence and detailed structure of Airy Rings or Point Spread Function(PSF)in your telescope, how do you explain operation or design of the multi anti reflection coatings on your camera or refractor object lens, Young’s two slit, Maser, Laser, Synchrotron.
. Maxwell's equations have no upper frequency limit as far as I am aware. Photon counting is a misnomer, photo-multiplier tubes (PMT) do not exclusively count photons, they count noise and “photons”, and there is no one for one correlation between signal and out put pulses or Feynman’s clicks.
. Radio astronomers often operate at a similar or better signal to noise ratio than QM’s counting photons. The units that radio astronomers use is the Jansky about 1e-26 watts/m^2/Hz moderrn state of the art astronomers using liquid helium etc. use micro Janskys 1e-32 watts/m^2/Hz.
. They also operate in the TeraHertz range. This means that radio astronomers can have a similar RF photon to noise ratio as the QM’s doing photon counting experiments. EPR experimenters do long averaging runs with and without signal and then subtract “dark” counts. There is also two “free parameters” you can adjust, these consist threshold detectors following the PMT’s. The only classical theories that have been rejected by clumsy tests of this type are billiard ball models, all possible no photon, Maxwellian wave models, are alive and well, entanglement, the hinge-pin of the quantum computer, is not proven by the last 40 or so EPR tests. J. S. Bell, although very critical of QM, still accepted the existence of the photon, resulting in all his Bell inequalities, only apply to billiard ball models


. I am one of those extremely rare individuals, that does not believe in photons.
However I’m not completely alone in this belief. Max Plank, often considered to be the father of quantum mechanics, certainly one of the founding members, also did not not subscribe to belief in the photon. In fact, Max and Albert Einstein had heated debates on this matter, ending in damage to their close relationship.
Max believed that discrete units of energy were emitted by matter or atoms, and travelled through space as per Maxwell’s equations. As the field drops off with distance, matter or atoms capable of detecting the field will need help from some other energy source to boost the radiated field that has fallen below a “Plank Unit of Energy” at the detector site.
Max developed a theory, that a sea of energy, just below the level of “Planck’s Constant” exists, this energy plus various sources of noise, provide the missing energy at the detector site.

Albert ignored Max’s theory and published his own theory of “energy packets”, without consulting Max, Max was extremely disappointed, and never contributed much to mainstream quantum mechanics after this incident. Max’s sea of energy had few supporters for many decades, but had somewhat of a renaissance a few years back by a small group that proposed a theory by the name of stochastic electrodynamics (SED), Max’s energy sea is incorporated into this theory, and goes by the name of “Zero Point Radiation”(ZPR). Mainstream Quantum Mechanics(QM) have incorporated a similar sea of energy by the name of “Quantum Noise”(QN), except that they consider it to be “virtual Energy”(VE), rather than “real”, as SED supporters claim. QM’s also claim that “Virtual Particles”(VP) exist in this sea.
. There is a new variation on the SED theory, SED with spin, SEDS


W. E. Lamb Jr. received the Nobel Prize for the measurement of the “Lamb Shift”, one of the two most precise measurement in science. W. E. Lamb Jr. published a paper, titled “Anti-Photon”

Anti-photon W.E. Lamb, Jr. Optical Sciences Center, University of Arizona, Tucson, AZ 85721, USA Received: 23 July 1994/Accepted: 18 September 1994

Appl. Phys. B 60, 77-84 (1995)

“G. Wentzel (1926) and G. Beck (1926) showed that the new quantum theory could describe the photoelectric effect correctly, without any use of "photons" or light quanta, using only a classical time-dependent electromagnetic field. They made use of first-order quantum mechanical perturbation theory applied to an atom. Their theory gave all of the features required by Einstein in 1905, and, in addition, gave an expression for the rate of the photo process. Of course, in 1905 and in 1917, Einstein did not have quantum mechanics (and would not have liked it if he had). In the 1926 work of Wentzel and Beck, the energy of the ejected photo electron was given by the frequency resonance condition of the perturbation theory when its equation was multiplied throughout by Planck's constant. The energy hv of a photon did not enter the calculation in any way, only its frequency v. This problem was given as an exercise in L. Schiffs text book on Quantum Mechanics. Much later, W. E. Lamb and M. O. Scully [9], and H. Fearn, and W. E. Lamb [10] made more detailed calculations on the atomic photoelectric effect.”


. Plank famously stated what’s become known as “Planck’s principle”: “A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die and a new generation grows up that is familiar with it.” In other words, new ideas do not advance by evidence, argument, and persuasion, but rather by older thinkers with older ideas passing away.

. Max's private life was filled with tragedy. His first wife died in 1909, his eldest son was killed in 1916 during World War I, and both his daughters died in childbirth. His home in Berlin was destroyed by fire after an air raid in February 1944, and his second son was suspected of involvement in the plot to assassinate Hitler and executed in 1945.

Cheers Barry
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Old 15-04-2020, 12:54 PM
bgilbert (Barry gilbert)
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G'day Ray.

. As an radio amatuer and amateur radio astronomer, I felt that your comment about " RF design techniques" was a bit of a put down. But then I remembered that I spent 45 years in the communication industry (microHz to 300 TeraHz) and could confidently respond, although my physics is a bit pathetic, as you have already gathered. i'll give it a go though. One of the biggest breakthroughs in fibre optics, was frequency domain multiplexing. using heterodyne techniques from circa(1930) radios.

. The PSF in your telescope, that you just, "put up with", cos most astronomers don't understand it. A QM, would probably tell you it's the uncertainty principle kicking in, or some such "twaddle". If you asked an old RF bloke, he'd say, the're just sidelobes we can eliminate (almost) or control those. Opticians have tried "apodization" without much success.

. Then there is those spider vanes in newtonians, and the spikes they produce (some astronomers have learnt to luv em?). I don't think they like the crappy PSF that the central obstruction causes in newts and some new designs coming onto the scene. Whatever you do, don't ask a QM to help you, they are busy with inflation, many worlds, dark stuff, entanglement etc.

RF bloke,
Barry

Last edited by bgilbert; 15-04-2020 at 01:05 PM.
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Old 16-04-2020, 12:21 PM
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Shiraz (Ray)
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Quote:
Originally Posted by bgilbert View Post
. G'day Ray

. With respect, I think you have missed the point, I’m trying to demonstrate a principle that can be adapted to any frequency. The “Photo Electric Effect” is considered a crucial stumbling block for classical theory, I’m basically proposing that metals could have the equivalent of a “High Pass Filter”(HPF) in their surface. The simplest HPF is a hollow open ended cylinder.
. Photon counting is a misnomer, photo-multiplier tubes (PMT) do not exclusively count photons, they count noise and “photons”, and there is no one for one correlation between signal and out put pulses or Feynman’s clicks.
. I am one of those extremely rare individuals, that does not believe in photons.

Cheers Barry
Hi Barry.

As I understand it, classical theory makes some completely wrong predictions about photoelectricity as follows:

1. all radiation is capable of producing photoelectrons. In experiments, there is a radiation cutoff frequency for a given material, below which there are absolutely no photoelectrons regardless of radiation intensity. Wrong prediction.

2. as the frequency increases, the number of photoelectrons will increase. In experiments, as the frequency increases, the energy of the photoelectrons increases, not their numbers. Wrong prediction.

3. as the intensity increases for a given frequency, photoelectron energies increase. In experiments, as the intensity increases, the number of photoelectrons increases, but they have the same energy. Wrong prediction.

4. there will be a delay between the start of illumination and the production of photoelectrons. Experimentally, there is no consistent delay. Wrong prediction.

ie, classical theory fails (spectacularly) to predict experimental results when dealing with photoelectricity - which is why Einstein wrote his well known paper... Your proposal above that metals may somehow incorporate a high pass filter could possibly get around point 1. but will not change the other wrong predictions. Since classical theory gets it wrong when dealing with emission and detection of light, it makes sense for us astronomers to use photon concepts when thinking about sources and detectors.

As for "believing" in photons, the question becomes what to use instead - many alternative (mathematically purer) approaches have been proposed over the years, but nothing yet seems to have supplanted the photon. At the most pragmatic level, "photons are what photodetectors detect" (not sure where I read that). I had personal experience of the reality of photons as detectable entities when designing a photon counting system for a UV spectrometer (40 years ago). It was clear as day, when looking the irregular stream of consistent pulses in the scope output, that the RbTe photocathode of the pm tube was responding to a random stream of discrete packets of light when the intensity was low. Call them what you will and maybe the "light particle" idea is a bit simplistic, but the reality of photodetection can be described very accurately as the detection of quanta of light energy. There is also a vast array of published research on the nature of photons, including work on how they can be applied as individual entities - even to the extent of showing experimentally what the shape of the wavefunction is - photons are here to stay.

It is also equally true that light can behave like a continuous electromagnetic wave when it passes through an interference filter or an optical system etc. My understanding is that the wave-particle duality concept is simply a way of framing the demonstrably real behaviours of light in different circumstances - in a way that makes some sort of sense to humans. The basic problem is that light often behaves counter to our intuition and commonsense.

Cheers Ray

Last edited by Shiraz; 17-04-2020 at 01:16 PM.
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Old 20-04-2020, 08:49 AM
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Shiraz (Ray)
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Quote:
Originally Posted by bgilbert View Post
G'day Ray.

. As an radio amatuer and amateur radio astronomer, I felt that your comment about " RF design techniques" was a bit of a put down. But then I remembered that I spent 45 years in the communication industry (microHz to 300 TeraHz) and could confidently respond, although my physics is a bit pathetic, as you have already gathered. i'll give it a go though. One of the biggest breakthroughs in fibre optics, was frequency domain multiplexing. using heterodyne techniques from circa(1930) radios.

. The PSF in your telescope, that you just, "put up with", cos most astronomers don't understand it. A QM, would probably tell you it's the uncertainty principle kicking in, or some such "twaddle". If you asked an old RF bloke, he'd say, the're just sidelobes we can eliminate (almost) or control those. Opticians have tried "apodization" without much success.

. Then there is those spider vanes in newtonians, and the spikes they produce (some astronomers have learnt to luv em?). I don't think they like the crappy PSF that the central obstruction causes in newts and some new designs coming onto the scene. Whatever you do, don't ask a QM to help you, they are busy with inflation, many worlds, dark stuff, entanglement etc.

RF bloke,
Barry
Genuinely no putdown intended Barry - RF engineering is a noble profession, as is the study of quantum physics.

Telescope PSF is a very well developed area of astronomy - why would you think otherwise? for eg http://adsabs.harvard.edu/full/1996PASP..108..699R and http://www.eso.org/sci/meetings/2015...apping_PSF.pdf

Apparently it is possible (but difficult) to study light diffraction using quantum concepts and it is possible that there are some secondary effects that are not predicted by wave theory (although I have only skimmed this paper!). https://arxiv.org/pdf/1011.3593.pdf

It is also possible to resolve well inside the Rayleigh limit using quantum/photon techniques eg https://arxiv.org/pdf/1712.02200.pdf. Some of the published experimental results for the various types of quantum microscopy are astonishing eg https://physicsworld.com/a/quantum-m...hydrogen-atom/. I doubt that quantum imaging concepts will appear in our hobby, since we are generally limited by the atmosphere (with larger amateur scopes) and the Rayleigh limit is not the problem. However, it would be interesting to see if any of the quantum imaging techniques could be applied to space telescopes in the future eg https://arxiv.org/pdf/1906.02064.pdf.

we live in interesting times Barry. Cheers Ray

Last edited by Shiraz; 20-04-2020 at 04:35 PM.
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Old 20-04-2020, 10:15 PM
bgilbert (Barry gilbert)
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G'day Ray
Quote:
As I understand it, classical theory makes some completely wrong predictions about photoelectricity as follows:

1. all radiation is capable of producing photoelectrons. In experiments, there is a radiation cutoff frequency for a given material, below which there are absolutely no photoelectrons regardless of radiation intensity. Wrong prediction.

2. as the frequency increases, the number of photoelectrons will increase. In experiments, as the frequency increases, the energy of the photoelectrons increases, not their numbers. Wrong prediction.

3. as the intensity increases for a given frequency, photoelectron energies increase. In experiments, as the intensity increases, the number of photoelectrons increases, but they have the same energy. Wrong prediction.

4. there will be a delay between the start of illumination and the production of photoelectrons. Experimentally, there is no consistent delay. Wrong prediction.

ie, classical theory fails (spectacularly) to predict experimental results when dealing with photoelectricity - which is why Einstein wrote his well known paper... Your proposal above that metals may somehow incorporate a high pass filter could possibly get around point 1. but will not change the other wrong predictions. Since classical theory gets it wrong when dealing with emission and detection of light, it makes sense for us astronomers to use photon concepts when thinking about sources and detectors.

. . I forgot to reply to an earlier post on the photoelectric effect, Lamb as you may know is a QM, and Nobel Laureate, which make the following paper even more interesting:
.
. https://ntrs.nasa.gov/archive/nasa/c...9680009569.pdf
.
. . I can return to this subject, to elaborate more on a pure Maxwellian view as distinct from a classical view, surprisingly QM, and the Maxwellian view AGREE!
.
Cheers
Ray
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Old 14-05-2020, 11:15 PM
bgilbert (Barry gilbert)
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G'day Ray

I have been neglecting IceInSpace of late, mainly because I was encouraged to enter into a physics essay competition. You may want to have a look at my submission? Put FQXi.org into Google, and then click on, read, comment, rate, essays, or something similar, then search for my name in about 300 other names or enter my name into the little search box on the left. Don't be too harsh on me I'm deep in enemy territory, and dodging slings and arrows like crazy! If I survive, I'll resume my heresy back here at IIS.

Cheers
Barry
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Old 12-06-2020, 11:46 PM
bgilbert (Barry gilbert)
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Originally Posted by Shiraz View Post
not my radio Barry.

RF photons are about 8-9 orders of magnitude less energetic than visible ones and are completely undetectable as individual entities....as far as I know, individual photons are detectable in the microwave region (just), but not at longer wavelengths.

Seems to me that it makes no sense to try to use photon concepts when dealing with radio waves. Just as it makes no sense to use RF design techniques when dealing with gamma-ray photons. Horses for courses.

Cheers Ray
G'day Ray

Why not use the theory that works the best and is paradox free. I was not aware that Maxwell broke down at gamma-ray frequencies.

Cheers
Barry
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