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Quantum Mistake!


geoff

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HiYa, I've tried posting this one on mainstream physics sites, it is either trashed immediately, or I get some personal invalidation then it's taken down,, so I am Confident I've just blown QM out the water!

 

 Max Plancks 1898 experiment 'The Photoelectric effect'

 

in 1898 they knew an electron had mass, and it was probably held in position on a zinc atom as a result of the electrostatic attraction to the nucleus so it is effectively a sprung mass

 

Red light is below the resonant frequency of the electrons which is why they don't absorb the energy of the red light 

 

no photons required!

 

Really simple ,obviously I have answers to the next questions, If you're adult human and you believe in particles this will stress you!

 your pulsating particle(that ***** cat!) is a wave in an aether . 

 

 

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HiYa, I've tried posting this one on mainstream physics sites, it is either trashed immediately, or I get some personal invalidation then it's taken down,, so I am Confident I've just blown QM out the water!

 

 Max Plancks 1898 experiment 'The Photoelectric effect'

 

in 1898 they knew an electron had mass, and it was probably held in position on a zinc atom as a result of the electrostatic attraction to the nucleus so it is effectively a sprung mass

 

Red light is below the resonant frequency of the electrons which is why they don't absorb the energy of the red light 

 

no photons required!

 

Really simple ,obviously I have answers to the next questions, If you're adult human and you believe in particles this will stress you!

 your pulsating particle(that ***** cat!) is a wave in an aether . 

I'm not surprised you've had this taken down on other sites. Here are some issues for you to address:

 

1) what evidence do you have that Max Planck did any work on the photoelectric effect, in 1898 or any other year? I have never heard of this.

 

2) In 1898 nobody had any idea of the nucleus of the atom. The prevailing model until about 1908 was the "plum pudding" model, in which electrons were embedded in some substance comprising the atom. It was Rutherford, Geiger and Marsden's experiments in 1908-1910 or so, bombarding gold foil with alpha particles, that showed for the first time that the mass of the atom was concentrated in a tiny nucleus at the centre and most of the rest was empty space.  More here: https://en.wikipedia.org/wiki/Geiger–Marsden_experiment

So I'm afraid you have got your history a bit wrong here.

 

3) Your model of the electrostatic attraction as a spring is obviously wrong if you think about it for moment. With a spring, once there is no more tension in the spring, i.e.when it gets to its natural unstretched length, it stops exerting a force. And if you push on it, it springs back in the opposite direction. But electrostatic attraction just gets stronger and stronger as the charged bodies get closer. So you don't expect to get a resonating system from it. To get that, you would need something to be pushing the electron away from the nucleus if it got too close. How do you account for that, on the basis of electrostatic forces?  

 

4) Once the Bohr model of the atom came into being, with a tiny +ve nucleus and electrons circulating round it, nobody could explain why the electron did not radiate energy, as it should have done by classical electromagnetic theory,  and spiral into the nucleus. You do not take that into account. 

 

QM accounts for all these difficulties.

 

If you had taken the trouble to read the history of QM, you would know all this. It looks to me as if you are a classic example of arguing from a position of ignorance about the thing you are criticising. THAT will be why your posts have been taken down on other, tougher, sites than this one. I'm very happy to discuss this further however. I think it is a really interesting subject.  

Edited by exchemist
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Hi,thanks for your response,

 

to be fair I'm not sure where I got the specific date from but, at the end of the 19th century results from black body experiments suggested there were increments in the emissions, suggesting Hooke may have been on to something before Newton convinced everyone light was a wave and the corpuscule theory was dropped, Hooke was at the time a giant of the scientific world, but anyway, planck did investigate this along with others and got a nobel prize for his work, the energy of the emitted electrons is calculated using 'K' plancks constant multiplied by the frequency of the light used in the experiment known as 'the photoelectric effect' .the actual experiment I actually did in class involved a gold leaf electroscope and a zinc plate and some fuss with the blue light because of the UV in it, but if you google max planck or black body radiation there will be lots on the subject, but yeah max was not the first to do the experiment but his analysis of the results is the basis for the wave/particle or photon model which last I heard requires 11 dimension's to keep the mathematicians happy

 

your absolutly right, in one of my taken down posts I mentioned the plum pudding model, but one thing they did know was when electrons were emitted by for example a zinc plate in blue light the plate became positively charged so whatever the configuration it may have been reasonable to assume electrostatic charges were involved some how,

 

3 when using the word sprung I was referring to the properties of your steel spring whilst operating in conditions of elastic deformation , had I used the term 'elastic bond' the  meaning may have been clearer, plastic deformation as you describe is not 'sprung' and occurs as a result of the breakdown of the inter-crystyline structure of the steel, google Hooke's law. The pushing away effect can be explained anyway you like all they did know was the electron was on and offable, the experiments were providing clues as to what might be going on, the results of the experiment fit the expected results of a wave model

 

4 good point , the light wave releases one whole cycle  of itself to the electrons , 0.76 of a light wave cycle cannot exist, so the energy of your emissions jumps up in increments as observed in both black body and photoelectric experiments, it also works with more contemporary models of the atom , your classic model suggest's smooth energy transfer rather than chunks, or quanta so I'm suggesting a quanta is one complete cycle, but this is going several steps of logic from my  point

 

My point is this, the experiment can be explained using resonance as rational for red light not releasing electrons which is pure wave theory it does not require light to exist as photons only, to explain the results . It is the particle part of the model that is the problem, one hundred years or so  ago most people wanted to believe stuff was solid at some level, the idea that we are composed entirely of waves and vibrations in an un-observable aether was just a step too far unless you were tesla.

 

 

again many thanks geoff

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Hi,thanks for your response,

 

to be fair I'm not sure where I got the specific date from but, at the end of the 19th century results from black body experiments suggested there were increments in the emissions, suggesting Hooke may have been on to something before Newton convinced everyone light was a wave and the corpuscule theory was dropped, Hooke was at the time a giant of the scientific world, but anyway, planck did investigate this along with others and got a nobel prize for his work, the energy of the emitted electrons is calculated using 'K' plancks constant multiplied by the frequency of the light used in the experiment known as 'the photoelectric effect' .the actual experiment I actually did in class involved a gold leaf electroscope and a zinc plate and some fuss with the blue light because of the UV in it, but if you google max planck or black body radiation there will be lots on the subject, but yeah max was not the first to do the experiment but his analysis of the results is the basis for the wave/particle or photon model which last I heard requires 11 dimension's to keep the mathematicians happy

 

your absolutly right, in one of my taken down posts I mentioned the plum pudding model, but one thing they did know was when electrons were emitted by for example a zinc plate in blue light the plate became positively charged so whatever the configuration it may have been reasonable to assume electrostatic charges were involved some how,

 

3 when using the word sprung I was referring to the properties of your steel spring whilst operating in conditions of elastic deformation , had I used the term 'elastic bond' the  meaning may have been clearer, plastic deformation as you describe is not 'sprung' and occurs as a result of the breakdown of the inter-crystyline structure of the steel, google Hooke's law. The pushing away effect can be explained anyway you like all they did know was the electron was on and offable, the experiments were providing clues as to what might be going on, the results of the experiment fit the expected results of a wave model

 

4 good point , the light wave releases one whole cycle  of itself to the electrons , 0.76 of a light wave cycle cannot exist, so the energy of your emissions jumps up in increments as observed in both black body and photoelectric experiments, it also works with more contemporary models of the atom , your classic model suggest's smooth energy transfer rather than chunks, or quanta so I'm suggesting a quanta is one complete cycle, but this is going several steps of logic from my  point

 

My point is this, the experiment can be explained using resonance as rational for red light not releasing electrons which is pure wave theory it does not require light to exist as photons only, to explain the results . It is the particle part of the model that is the problem, one hundred years or so  ago most people wanted to believe stuff was solid at some level, the idea that we are composed entirely of waves and vibrations in an un-observable aether was just a step too far unless you were tesla.

 

 

again many thanks geoff

Thanks for the reply.

 

Again, you seem to have got your history garbled - in fact back to front this time. Newton famously promoted a corpuscular theory of light, not a wave theory. It was Huygens (and Hooke) who promoted a wave theory. More here: https://en.wikipedia.org/wiki/Light#Wave_theory, see  section 7 on the history of theories of light. 

 

Your 2nd para is evidently about the photo-electric effect. It was Einstein who got his Nobel prize for explaining this as due to a quantum effect. 

 

Your 3rd para is too garbled for me to understand what you are trying to say. The bit about electrons being "on and offable" is particularly unclear. 

 

Your 4: you seem now to have moved to some kind of quantum model of the atom, except that you talk of 0.76 of a light wave cycle rather than whole number of electron waves.

 

In your final para I am not clear about what experiment you refer to. If it is the photoelectric effect then you can't explain that by resonance at a particular light frequency. If it were due to resonance, you would expect something special to happen only when the light frequency was an exact multiple of the resonance frequency of whatever was resonating. That is not what you get. You get nothing until a critical threshold frequency is reached and then, at all frequencies above this, you get electron emission.

 

Quantum theory accounts for this. 

Edited by exchemist
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my history in that respect is not good , but then it was never a part of physics courses, I think saying newton was famous for his corpuscular theory was pushing the boat out a tad too many, famous for the laws of motion , gravity etc and his work with refraction of light , prisms and the light spectrum, which is obviously the source of my misunderstanding of history. Max plank did coin the term quanta and it was albert who was credited with suggesting these were in fact real ,ok so I'm now saying albert got it wrong , great that's really going to help. But at least you now know who Max plank was ,not that any of this is relevant to my post or the science behind it. Other than of course QM was an attempt to explain the evidence as it was in the first decade of the last century, except it doesn't work now 

 

if I try and respond to your next points i'll probably just repeat myself

 

in 4 I am trying to explain that waves don't turn up in random size bits ,a 21cm column of air will support a 21 cm wave and its harmonic's but not a 19 cm wave with another 2cm of another 19 cm wave tacked on the end

 

In my model the quanta is the minimum amount of light that is viable, a whole cycle or complete wave and that energy transfer from light to electron only occurs one whole quanta in any one event, which is entirely consistent with planck's work . It does not ,however, require the light to exist as single quanta prior to its interaction with the electron. The 'energy packet' phenonmenon is to be expected as a natural and normal effect of wave dynamics , If the electron is a wave it will be locked into orbits around the nucleus  Last I heard these orbits are considered as 'energy shell's'. Your classic theory has the orbit gradually decaying which is inconsistent with observation so it's wrong,  so the photoelectric effect is so far explained without the need for a wave/particle model

 

the wave/particle model is used to explain the fact that red light does not release electrons whereas blue light does , now i don't remember ever being told the specific frequency that is the change over point as this will be ,I suggest, the resonant frequency of the system . Albert says that there is not enough energy in a red light photon to release an electron . I say that the electron is very reluctant to absorb energy at frequencies below resonance.

 

You seem to refer to some system that only resonates at the resonance point, dropping off untill reaching an exact multiple . I am unaware of any system that does this, all the systems I know of (and build) are very reluctant/inefficient below resonance then a very sharp peaking at resonance which then drops off slowly as the frequency rises and no obvious peaks at the 'multiple' points (i have a picture of a graph in my head as i write this), which describes the results from the photo electric effect experiment that QM puts forward as proof of wave particle duality , everything else works when one treats everything as waves and ignore the alleged particle component of the QM model. Im not saying quanta or photons do not exist ,they do , they are just the smallest viable wave

 

so if we could stick to the science and the specific experiment in question I would be grateful, although my history has improved as a result of this exchange!

 

so my point is if resonance can explain why red light is not absorbed we don't need particles to explain the photoelectric effect, which means albert got it wrong, which even I was less than happy with, but science doesn't do gods so even albert can get it wrong, people on the other hand do do gods, and rarely do they like it when their believe system is challenged which is what i'm doing.scientists are people and it was albert that pointed out we need to include the observer in any measurement (frames of ref.) And I add also the person making the measurements and interpreting them!

 

thanks  geoff

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my history in that respect is not good , but then it was never a part of physics courses, I think saying newton was famous for his corpuscular theory was pushing the boat out a tad too many, famous for the laws of motion , gravity etc and his work with refraction of light , prisms and the light spectrum, which is obviously the source of my misunderstanding of history. Max plank did coin the term quanta and it was albert who was credited with suggesting these were in fact real ,ok so I'm now saying albert got it wrong , great that's really going to help. But at least you now know who Max plank was ,not that any of this is relevant to my post or the science behind it. Other than of course QM was an attempt to explain the evidence as it was in the first decade of the last century, except it doesn't work now 

 

if I try and respond to your next points i'll probably just repeat myself

 

in 4 I am trying to explain that waves don't turn up in random size bits ,a 21cm column of air will support a 21 cm wave and its harmonic's but not a 19 cm wave with another 2cm of another 19 cm wave tacked on the end

 

In my model the quanta is the minimum amount of light that is viable, a whole cycle or complete wave and that energy transfer from light to electron only occurs one whole quanta in any one event, which is entirely consistent with planck's work . It does not ,however, require the light to exist as single quanta prior to its interaction with the electron. The 'energy packet' phenonmenon is to be expected as a natural and normal effect of wave dynamics , If the electron is a wave it will be locked into orbits around the nucleus  Last I heard these orbits are considered as 'energy shell's'. Your classic theory has the orbit gradually decaying which is inconsistent with observation so it's wrong,  so the photoelectric effect is so far explained without the need for a wave/particle model

 

the wave/particle model is used to explain the fact that red light does not release electrons whereas blue light does , now i don't remember ever being told the specific frequency that is the change over point as this will be ,I suggest, the resonant frequency of the system . Albert says that there is not enough energy in a red light photon to release an electron . I say that the electron is very reluctant to absorb energy at frequencies below resonance.

 

You seem to refer to some system that only resonates at the resonance point, dropping off untill reaching an exact multiple . I am unaware of any system that does this, all the systems I know of (and build) are very reluctant/inefficient below resonance then a very sharp peaking at resonance which then drops off slowly as the frequency rises and no obvious peaks at the 'multiple' points (i have a picture of a graph in my head as i write this), which describes the results from the photo electric effect experiment that QM puts forward as proof of wave particle duality , everything else works when one treats everything as waves and ignore the alleged particle component of the QM model. Im not saying quanta or photons do not exist ,they do , they are just the smallest viable wave

 

so if we could stick to the science and the specific experiment in question I would be grateful, although my history has improved as a result of this exchange!

 

so my point is if resonance can explain why red light is not absorbed we don't need particles to explain the photoelectric effect, which means albert got it wrong, which even I was less than happy with, but science doesn't do gods so even albert can get it wrong, people on the other hand do do gods, and rarely do they like it when their believe system is challenged which is what i'm doing.scientists are people and it was albert that pointed out we need to include the observer in any measurement (frames of ref.) And I add also the person making the measurements and interpreting them!

 

thanks  geoff

That's ridiculous. The history of how quantum theory arose is invariably part of any reasonable method of teaching it. Understanding the problems with classical physics that arose towards the end of the c.19th is how one understands the need for the counterintuitive concepts that QM introduced. Examples are:

 

- the "ultraviolet catastrophe"

- the photo-electric effect

- the structure of the atom

- atomic spectra.

 

If you never learnt why these posed difficulties for classical physics, I am not surprised that you fail to understand quantum theory.

 

Later footnote: I may come back separately on the specific issues about resonance, if I can summon up the energy to sort through the muddle and guess at the meaning of some of the imprecise language. 

Edited by exchemist
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my history in that respect is not good , but then it was never a part of physics courses, I think saying newton was famous for his corpuscular theory was pushing the boat out a tad too many, famous for the laws of motion , gravity etc and his work with refraction of light , prisms and the light spectrum, which is obviously the source of my misunderstanding of history. Max plank did coin the term quanta and it was albert who was credited with suggesting these were in fact real ,ok so I'm now saying albert got it wrong , great that's really going to help. But at least you now know who Max plank was ,not that any of this is relevant to my post or the science behind it. Other than of course QM was an attempt to explain the evidence as it was in the first decade of the last century, except it doesn't work now 

 

if I try and respond to your next points i'll probably just repeat myself

 

in 4 I am trying to explain that waves don't turn up in random size bits ,a 21cm column of air will support a 21 cm wave and its harmonic's but not a 19 cm wave with another 2cm of another 19 cm wave tacked on the end

 

In my model the quanta is the minimum amount of light that is viable, a whole cycle or complete wave and that energy transfer from light to electron only occurs one whole quanta in any one event, which is entirely consistent with planck's work . It does not ,however, require the light to exist as single quanta prior to its interaction with the electron. The 'energy packet' phenonmenon is to be expected as a natural and normal effect of wave dynamics , If the electron is a wave it will be locked into orbits around the nucleus  Last I heard these orbits are considered as 'energy shell's'. Your classic theory has the orbit gradually decaying which is inconsistent with observation so it's wrong,  so the photoelectric effect is so far explained without the need for a wave/particle model

 

the wave/particle model is used to explain the fact that red light does not release electrons whereas blue light does , now i don't remember ever being told the specific frequency that is the change over point as this will be ,I suggest, the resonant frequency of the system . Albert says that there is not enough energy in a red light photon to release an electron . I say that the electron is very reluctant to absorb energy at frequencies below resonance.

 

You seem to refer to some system that only resonates at the resonance point, dropping off untill reaching an exact multiple . I am unaware of any system that does this, all the systems I know of (and build) are very reluctant/inefficient below resonance then a very sharp peaking at resonance which then drops off slowly as the frequency rises and no obvious peaks at the 'multiple' points (i have a picture of a graph in my head as i write this), which describes the results from the photo electric effect experiment that QM puts forward as proof of wave particle duality , everything else works when one treats everything as waves and ignore the alleged particle component of the QM model. Im not saying quanta or photons do not exist ,they do , they are just the smallest viable wave

 

so if we could stick to the science and the specific experiment in question I would be grateful, although my history has improved as a result of this exchange!

 

so my point is if resonance can explain why red light is not absorbed we don't need particles to explain the photoelectric effect, which means albert got it wrong, which even I was less than happy with, but science doesn't do gods so even albert can get it wrong, people on the other hand do do gods, and rarely do they like it when their believe system is challenged which is what i'm doing.scientists are people and it was albert that pointed out we need to include the observer in any measurement (frames of ref.) And I add also the person making the measurements and interpreting them!

 

thanks  geoff

OK, let's have a go at the first part of this screed:-

 

First, why do you say Quantum Theory "doesn't work" now? What evidence do you have that it doesn't? Because last time I checked, the whole of chemistry and about half of physics depended on it - with great success. 

 

Second, your description of the behaviour of electrons in the atom is more or less what QM says. The electron has a wave character and can only be stable in orbitals corresponding to a series of spherical harmonics, i.e. resonant, standing wave, patterns. This wave character was the insight that overcame the problem of the predicted decay of the orbit, in the classical orbiting particle model of the electron in an atom. De Broglie was the person responsible for the concept of "matter waves", with his formula relating wavelength to momentum: λ = h/p. 

 

So far so good.

 

However when it comes to the photoelectric effect, your idea does not really work, for the reason I have already given. An explanation that relies on resonance would explain absorption at a critical frequency, but not expulsion of electrons at any forcing frequency higher than a minimum threshold value. If you try to force an oscillator at a frequency significantly above its resonance frequency, you don't get much response - and certainly a lot less than you get at the resonance frequency. Which is not what is observed.

 

But in any case, there are no such resonators in a metal. We know from the thermal and electrical conductivity of metals that the electrons are not attached to any one atom, but float in a "sea" of electrons, within an energy band structure. In fact this accounts for the shiny reflectivity of metals, since they can oscillate in response to any frequency of incident light, reflecting the wave back. (The threshold frequency for the photoelectric effect is usually in the UV rather than the visible region, so the absorption of light in the PE effect does not affect their visual appearance.)   

Edited by exchemist
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So what you'r saying ,I think, your 'threshold' frequency is in the UV range and is the point at which electrons are no longer emitted , so any frequency higher than UV does not emit electrons, This confirms there is a drop off in electron emission consistent with what one would expect, if I am correct. I am assuming a zinc plate here.

 

Red light does not release electrons, blue light does, so the 'lower threshold' would be the point somewhere in the visible spectrum where electrons begin to be released, that is, we have just reached the resonance point, As we carry on up the  frequency range the electrons are more energetic , frequency multiplied by planks constant gives one the kinetic energy of the little blighters ,

 

which is what i'm trying to say 

 

yes if it possibly can,a thing will oscillate when given a shove, but at resonance and for a period above energy transfer is highly efficient, giving the electron enough energy to escape from the zinc plate across the lab, 

 

So why do we need a photon ?

 

thank's,   geoff

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But in any case, there are no such resonators in a metal. We know from the thermal and electrical conductivity of metals that the electrons are not attached to any one atom, but float in a "sea" of electrons, within an energy band structure. In fact this accounts for the shiny reflectivity of metals, since they can oscillate in response to any frequency of incident light, reflecting the wave back. (The threshold frequency for the photoelectric effect is usually in the UV rather than the visible region, so the absorption of light in the PE effect does not affect their visual appearance.)   

 

 

I didn't know that. I do know about electron wave resonance in general:

 

I did not realize that it is entirely absent in metals.

 

What do you make of this paper then? Is it something entirely different from what you are referring to?

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I didn't know that. I do know about electron wave resonance in general:

 

I did not realize that it is entirely absent in metals.

 

What do you make of this paper then? Is it something entirely different from what you are referring to?

It's a bit different. When I tell Geoff there are no resonators in a metal what I mean is there are no resonating systems of the type he is trying to model, in which he has valence electrons attached to individual atoms by something resembling a spring.

 

This paper of yours caused me to do some revision about what we used to call ESR (now called EPR). :)  This is indeed a resonance in metals, but it is one that has to be provoked artificially by applying a magnetic field. This causes a splitting in energy between unpaired electrons at the top (in energy level terms) of the "sea" of electrons, according to whether the spins are aligned with the field or against it. Transitions between "down" and "up" states can be induced by microwave absorption, which is what ESR (EPR) measures.

 

But in the absence of an external field there is no resonance, because "up" and "down" spins are not defined, and the states become effectively degenerate (=have identical energy). 

 

The fact that there are some unpaired electrons in a metal (above absolute zero at least) that can align with an external magnetic field gives rise to "paramagnetism", which is described in a bit more detail here: http://users.aber.ac.uk/ruw/teach/334/mgncondel.php   N.B. This article is a bit misleading as it shows a band gap between the valence band and the conduction band, which is what you get in insulators and semiconductors, rather than in metals. In metallic conductors, the valence and conduction bands either overlap or the gap is very small compared to kT at normal temperatures, so that it effectively does not present a practical barrier to current flow.

Edited by exchemist
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So what you'r saying ,I think, your 'threshold' frequency is in the UV range and is the point at which electrons are no longer emitted , so any frequency higher than UV does not emit electrons, This confirms there is a drop off in electron emission consistent with what one would expect, if I am correct. I am assuming a zinc plate here.

 

Red light does not release electrons, blue light does, so the 'lower threshold' would be the point somewhere in the visible spectrum where electrons begin to be released, that is, we have just reached the resonance point, As we carry on up the  frequency range the electrons are more energetic , frequency multiplied by planks constant gives one the kinetic energy of the little blighters ,

 

which is what i'm trying to say 

 

yes if it possibly can,a thing will oscillate when given a shove, but at resonance and for a period above energy transfer is highly efficient, giving the electron enough energy to escape from the zinc plate across the lab, 

 

So why do we need a photon ?

 

thank's,   geoff

NO, yer berk! (Sorry). I thought you knew something about the photoelectric effect. Evidently not. 

 

You get no electrons ejected from the metal surface until you reach the threshold frequency and then you get electrons ejected at ANY higher frequency. If this threshold frequency is in the UV, as it usually is, neither "red" nor "blue light releases electrons, because both are lower frequency than UV. 

 

This is pretty hopeless: at every turn you reveal new things that you don't understand. 

Edited by exchemist
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so with zinc the threshhold frequency is up in the UV range ,ok ,its over thirty years since I did this ,there are other metals with lower frequencies, so nothing changes there.  you say at ANY higher frequency  I haven't found an answer to that question yet, 

 

the idea that I had an image of an actual metal spring in my head is very silly , I think I qualified that as an elastic bond of some sort, and when I say 'elastic' its a description of a material's property.  A pendulum in a grandfather clock is sprung by the acceleration due to gravity acting on it, most people will understand this statement, and one could work out the 'spring rate' of this system ,yet there is no spring!

 

You accept that electrons oscillate so its reasonable to assume for any given system that there will be a resonant frequency specific to that system

 

so why do we need a photon?

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so with zinc the threshhold frequency is up in the UV range ,ok ,its over thirty years since I did this ,there are other metals with lower frequencies, so nothing changes there.  you say at ANY higher frequency  I haven't found an answer to that question yet, 

 

the idea that I had an image of an actual metal spring in my head is very silly , I think I qualified that as an elastic bond of some sort, and when I say 'elastic' its a description of a material's property.  A pendulum in a grandfather clock is sprung by the acceleration due to gravity acting on it, most people will understand this statement, and one could work out the 'spring rate' of this system ,yet there is no spring!

 

You accept that electrons oscillate so its reasonable to assume for any given system that there will be a resonant frequency specific to that system

 

so why do we need a photon?

I don't really see the point in constructing a long answer for someone who is too lazy even to look up the photoelectric effect, when he wants to talk about it 30 years after he last had anything to do with it. How on Earth can you expect to be taken seriously if you try to challenge one of the cornerstones of c. 20th physics and chemistry based on vague and faulty memories from 30 years ago that you have not even checked?  

 

Look, if you bear in mind (i) that the electrons ejected cannot come from resonating electron states, for the reasons I have explained and (ii), that classical physics expected the ejection to depend on intensity not frequency, then you should see why Einstein's photons were needed.   

 

You can read all about this for yourself if you look up "photoelectric effect". If you now do this and then come back with further questions or issues, I will try to help. But please do at least a bit of work for yourself on this before you start asserting QM is wrong.

 

There are by the way plenty of other pieces of evidence for the existence of photons. We can go into some of that later, if you are willing to do a bit of homework first. :)

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It's a bit different. When I tell Geoff there are no resonators in a metal what I mean is there are no resonating systems of the type he is trying to model, in which he has valence electrons attached to individual atoms by something resembling a spring.

 

This paper of yours caused me to do some revision about what we used to call ESR (now called EPR). :)  This is indeed a resonance in metals, but it is one that has to be provoked artificially by applying a magnetic field. This causes a splitting in energy between unpaired electrons at the top (in energy level terms) of the "sea" of electrons, according to whether the spins are aligned with the field or against it. Transitions between "down" and "up" states can be induced by microwave absorption, which is what ESR (EPR) measures.

 

But in the absence of an external field there is no resonance, because "up" and "down" spins are not defined, and the states become effectively degenerate (=have identical energy). 

 

The fact that there are some unpaired electrons in a metal (above absolute zero at least) that can align with an external magnetic field gives rise to "paramagnetism", which is described in a bit more detail here: http://users.aber.ac.uk/ruw/teach/334/mgncondel.php   N.B. This article is a bit misleading as it shows a band gap between the valence band and the conduction band, which is what you get in insulators and semiconductors, rather than in metals. In metallic conductors, the valence and conduction bands either overlap or the gap is very small compared to kT at normal temperatures, so that it effectively does not present a practical barrier to current flow.

 

 

 

Thanks for your informative reply. At the moment I am too occupied with other matters to make a coherent response, but I intend to come back to this soon; as I find it interesting.

 

I do have "one" quick question for you that I have been thinking about: What do you think of the idea that magnetic B field consists of photons? I ask in relation to ESR/EPR. Can it be that even here the effect seen comes down to photons, as it does in PE effect? (although by very different mechanisms)

 

If photons are involved in a static magnetic field, what frequency would they have? Can a zero frequency photon exist, and if so how could it transfer any momentum to an electron?

 

Ok, that is more than one quick question! :innocent: 

 

I am not trying to pin you down on anything either; just interested in your thoughts about these things.

 

Unfortunately, I could not get your link to work, although I was greeted by some interesting Welsh!

•A yw'r cyfeiriad wedi ei deipio'n gywir? Gwnewch yn sicr nad oes camgymeriadau sillafu. :out:

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Unfortunately, I could not get your link to work, although I was greeted by some interesting Welsh!

•A yw'r cyfeiriad wedi ei deipio'n gywir? Gwnewch yn sicr nad oes camgymeriadau sillafu. :out:

 

Pathetic language politics from Aberystwyth - as if anybody discussing physics could actually do it in Welsh. Or most other subjects, for that matter.

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Thanks for your informative reply. At the moment I am too occupied with other matters to make a coherent response, but I intend to come back to this soon; as I find it interesting.

 

I do have "one" quick question for you that I have been thinking about: What do you think of the idea that magnetic B field consists of photons? I ask in relation to ESR/EPR. Can it be that even here the effect seen comes down to photons, as it does in PE effect? (although by very different mechanisms)

 

If photons are involved in a static magnetic field, what frequency would they have? Can a zero frequency photon exist, and if so how could it transfer any momentum to an electron?

 

Ok, that is more than one quick question! :innocent: 

 

I am not trying to pin you down on anything either; just interested in your thoughts about these things.

 

Unfortunately, I could not get your link to work, although I was greeted by some interesting Welsh!

•A yw'r cyfeiriad wedi ei deipio'n gywir? Gwnewch yn sicr nad oes camgymeriadau sillafu. :out:

Sorry for the Welsh, I don't know why you got that. I didn't see it. 

 

I don't know very much about QED, which I think may be what you are getting at with your comments about magnetic fields consisting of photons. Photons certainly do consist of oscillating magnetic and electric fields, but I do not think one can say that a magnetic field consists of photons - certainly not real ones.

 

When it comes to these mathematic entities known as "virtual" photons, I once read a very nice piece lamenting the choice of terminology, as it has led people, erroneously, to think that virtual photons "are" photons, when all they are is disturbances in the EM field that can be modelled mathematically rather like photons. 

 

But of course EPR/ESR does involve absorption of photons. It is just that they are photons of microwave frequency, i.e. carrying a small amount of energy, corresponding to the size of the splitting in energy level between the "up" and "down" states of unpaired electrons in the static field.

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