[yor_on]

Hmm, seem I deleted the wrong comment? Or that the server did.

Anyway, I agree BC. also I think the way they accommodated her needs was from part compassion, part curiosity, to what she might have thought up. Not everyone is nice, doesn't mean they can't have original thinking though.

[mxplxxx (OP)]

" So, a whole branch of physics was started based on an educated guess and 100 years later noone can prove whether the guess was correct or not:)."

It's not like that, one way of looking at it might be from a point of trial and error. With that comes new ideas and definitions. You find a experiment to give you some really weird results, that starts you thinking, and you search for a way to make it make sense. Later experiments may be constructed to test that idea. That's one of the most important things you need to do, to find that experiment testing your new thoughts. That way everything builds, there's a lot of new definitions today, that wouldn't have made sense to people a hundred and fifty years ago. You follow the way nature presents itself and then you search for how to explain it. It lead us to probabilities, lights duality, superpositions, relativity, conservation laws, etc etc.  You can't ignore nature.
=

Everything is a educated guess, isn't it? From you stepping out your door, expecting yourself to exist tomorrow too, to getting an idea of a new way to do something. There are no certainties in life, and modern physics is built to accommodate this.

Wave/particle duality as an idea is a different kettle of fish isn't it?. The idea that a quantum entity exists in a superposition of evolving states (btw a concept that physics has difficulty explaining) until it is observed when it, apparently magically, turns into a particle at a fixed place in space/time takes a great deal of accepting. Especially when the nature of an an observation is not well defined. One cannot help but think (as Einstein did) that another as yet unknown mechanism is at work. Personally I love the theory as it appears to make the universe a very personal place where your choices in life lead, incredibly, to very definite outcomes. This may be your personal universe and the rest of us are just players.

[PmbPhy]

The photon behaves like a particle and a wave.

All elementary particles, including photons, have wave properties depending on the experiment used detect then. A single photon passing through a double slit behaves like a particle. However the wave properties are apparent when one repeats the experiment a large number of times (either by using the same apparatus or having a multitude such apparatus. The repetition is called an ensemble (aka collection).

By the way. The wave of a proton depends of the wave function and varies the same way that one can't simply ask "What is the energy of a photon?"

[mxplxxx (OP)]

Actually, all photons have the same energy (Planck's constant joules), but different power. Energy comes in units called quanta - and this is the basis of quantum theory. A photon always contains one quantum of energy. A lower power photon will not knock an electron from a black body but a higher power one will. See  https://www.google.com/search?rlz=1C1CHBD_en-GBAU826AU826&ei=3xccXKyMJsSS9QOi2IfYAg&q=plancks+constant+energy+of+one+cycle&oq=plancks+constant+energy+of+one+cycle&gs_l=psy-ab.3...584984.596812..597188...0.0..0.415.9758.2-30j5j1....2..0....1..gws-wiz.......0j0i71j0i67j0i131j0i10j0i22i30j0i13j0i8i13i30j0i22i10i30j33i22i29i30j33i160.Q_EF2BHDRkU

[alancalverd]

Not true.

Planck's constant does not have the dimensions of energy.

Power is the rate of deposition or expenditure of energy. The power of a photon beam depends on the density of photons. The notion that a single photon has power is meaningless.

Energy is not necessarily quantised.

Different photons have different energies. A blue photon has about twice the energy of a red photon, which is why we see color, and an x-ray photon has about 10,000 times as much energy, which is why we can photograph the insides of things.

"Knocking an electron from a black  body" is a meaningless collection of pseudoscientific words.

If you want to sing opera, it's a good idea to learn some Italian and stick to the music. If you want to discuss physics it's a good idea to learn the language and respect the dimensions.

[Bored chemist]

Did you consider finding out how science works before trying to tell everyone that it's wrong?

Not wrong. Not right. Just unproven:).

The way science works it to accept that most things are unproven. But what's important is that you can at least discard the stuff that's disproven.

That policy has, in fact, been shown to work- for example- you computer works. Planes fly medicines cure disease.

Discounting that sort of evidence just makes you look silly.

[Bored chemist]

Actually, all photons have the same energy (Planck's constant joules), but different power. Energy comes in units called quanta - and this is the basis of quantum theory.

Like I said, it would be a good idea to learn some science before trying to criticise it.
Hint; red photons have roughly half the energy of violet one.

[Bored chemist]

I have had to do an enormous amount of research.

What research did you do that left you so ignorant of fairly basic science?

[PmbPhy]

Actually, all photons have the same energy (Planck's constant joules), but different power. Energy comes in units called quanta - and this is the basis of quantum theory.

That is incorrect. Different photons can have different energy. If they were all the same energy then the rainbow would not be colorful. Watching a movie means seeing different colors. Different colors means different photon energies. Where did you get idea otherwise?

Energy is not always quantized in QM. For a the energy of a particle to be quantized it must be in potential well.

You should study physics in more detail since your basic understanding is quite wrong. I recommend picking learning math and physics from college level texts. They usually explain the physics/math quite well.

By the way. Planck's constant is not in units of energy. It's in units of action = [Joules-sec].

[mxplxxx (OP)]

Higher power photons have shorter wavelengths than lower power photons. This means they transfer their energy quicker. But the total amount of energy transferred is the same for all. You can fire a beam of low power photons at (say) a piece of aluminium and it will not knock any electrons from the aluminium irrespective of how intense the photon beam is. The higher power photons will knock electrons from the aluminium irrespective of the intensity of the photon beam. This fact was discovered by Einstein in his basic quantum research. See https://www.pitt.edu/~jdnorton/teaching/HPS_0410/chapters/quantum_theory_origins/ Photoelectric Effect.

See also https://www.researchgate.net/publication/325462944_Planck's_Constant_and_the_Nature_of_Light.
.

Note also that any discussion of photons in quantum theory is hindered by the fact that we don't know what the wave function of a photon is. We are totally reliant on the classical description of light as a transverse electromagnetic wave.

[PmbPhy]

Higher power photons have shorter wavelengths than lower power photons.

You're wrong. It's a physical fact that different photons have can have different energies. Its meaningless to speak of a photon having a certain amount of power. Do you know what power is? Its the energy of a system divided by the amount the energy changes over a period of time. I.e. P = dE/dt

[mxplxxx (OP)]

"Knocking an electron from a black  body" is a meaningless collection of pseudoscientific words.

True! I use aluminium as an example in my latest post.

[PmbPhy]

Higher power photons have shorter wavelengths than lower power photons. This means they transfer their energy quicker.

Wherever you heard/learned that, you're till wrong and you're refusing to state where you learned it so this is my last post in this thread until you do.

I know the principles of quantum mechanics as well as any physicist and that's from advanced QM texts all of which agree all which confirm that different photons can have different energies and that the power of a photon is meaningless.

And there is a wave function of a photon which shows you're assumption otherwise to be wrong. Different photon possibly different wave function.

Later gator.

[mxplxxx (OP)]

You're wrong. It's a physical fact that different photons have can have different energies. Its meaningless to speak of a photon having a certain amount of power. Do you know what power is? Its the energy of a system divided by the amount the energy changes over a period of time. I.e. P = dE/dt

Sure I know what power is. I also know what energy is. In joules, it is "equal to the work done by a force of one newton when its point of application moves one metre in the direction of action of the force". No time involved in this. But time is involved in probably the most basic equation of quantum physics E= hf which gives the energy of a particle that will be transferred in 1 second. This is a power unit. The energy that will be transferred in one cycle is E/f which is h which is always the same for all particles. People confuse energy and power and this seems to have happened sometime in the past with physics (unless I am horribly wrong - always a possibility:).

[Bored chemist]

unless I am horribly wrong

You are.
Several of us have pointed this out.
You are refusing to listen.

What are you doing here if you willfully decline to learn?

[mxplxxx (OP)]

Several of us have pointed this out.

I need understanding, not directives. What is the underlying meaning of the E=hf equation? I have searched high and low for this to no avail. It seems its meaning has been lost in the sands of time. If any of you can provide a lucid explanation of the equation, I will take my hat off to you:).

[Bored chemist]

have searched high and low for this to no avail.

OK, So, if you googled it, you probably got the wiki page
https://en.wikipedia.org/wiki/Photon_energy

Which bits of it  do we need to explain?

Also, how did you come to the conclusion that an equation that gives 400 million his on google is " lost in the sands of time. "?

[mxplxxx (OP)]

have searched high and low for this to no avail.

OK, So, if you googled it, you probably got the wiki page
https://en.wikipedia.org/wiki/Photon_energy

Which bits of it  do we need to explain?

Also, how did you come to the conclusion that an equation that gives 400 million his on google is " lost in the sands of time. "?

Th Wiki page just repeats what countless others on the Internet say about the equation. They do not  discuss the meaning of the the equation and the concepts behind it and the implications for quantum theory. THey in particular do not discuss what the energy of a photon actually means. So Energy = a constant divided by the frequency of the photon. How does this come about? What is the frequency of a photon, especially given the wave function of a photon is not known. If it is the frequency of an EM wave, how does this apply to a quantum entity. The whole thing is a shocking mess. I am a systems analyst as well as a programmer and I can't work it out. And I am as smart as smart as can be with Uni maths as well.

Lost in the sands of time  ... The meaning of Action seems to have undergone several metamorphoses and I cannot work out what it means today.

[Bored chemist]

Energy = a constant divided by the frequency of the photon.

It's not divided by frequency, it is multiplied.

h Wiki page just repeats what countless others on the Internet say about the equation.

Well, it's probably correct.

They do not  discuss the meaning of the the equation

OK, what it says is "Photon energy is the energy carried by a single photon. "
Which words don't you understand?
Did you try googling them?

especially given the wave function of a photon is not known.

It is known.
It's just that you can't understand it.

And I am as smart as smart as can be with Uni maths as well.

It took you several tries to find a numbered equation in some text.
And now you are pretending that it doesn't exist.

How smart do you think that makes you look?

May I make a suggestion?
I'm going to be away from home a bit over the Xmas/ New year period, so why don't you take the chance to actually study this stuff.
You might start here.
https://www.khanacademy.org/science/physics/quantum-physics/modal/v/photon-energy

[jeffreyH]

Higher power photons have shorter wavelengths than lower power photons. This means they transfer their energy quicker. But the total amount of energy transferred is the same for all. You can fire a beam of low power photons at (say) a piece of aluminium and it will not knock any electrons from the aluminium irrespective of how intense the photon beam is. The higher power photons will knock electrons from the aluminium irrespective of the intensity of the photon beam. This fact was discovered by Einstein in his basic quantum research. See https://www.pitt.edu/~jdnorton/teaching/HPS_0410/chapters/quantum_theory_origins/ Photoelectric Effect.

See also https://www.researchgate.net/publication/325462944_Planck's_Constant_and_the_Nature_of_Light.
.

Note also that any discussion of photons in quantum theory is hindered by the fact that we don't know what the wave function of a photon is. We are totally reliant on the classical description of light as a transverse electromagnetic wave.

The energy of all photons is not the same. The quantum of action (h) is useless without the wavelength. The Planck constant is also not time dependent. Which it would have to be for your argument to be correct. Go and read a biography of Max Planck. I am currently reading "No time to be brief" the scientific biography of Wolfgang Pauli. You will find such study more rewarding than posting aimlessly on forums. Then you could come back and have a constructive debate.