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....cows moo at one end, poo at the other, and make milk in the middle.
Fourier tells us that we should be able to detect harmonics of the fundamental frequency. associated with, say, a LED or similar single spectral line. We can't.
you can't "validate" E = hf because it is the definition of h.
Quote from: alancalverd on 23/01/2019 13:58:26Fourier tells us that we should be able to detect harmonics of the fundamental frequency. associated with, say, a LED or similar single spectral line. We can't.Practically every "green laser" you see- and they aren't rare- is actually the second harmonic of an infrared laser beam.
In 1900, Max Planck empirically derived a formula for the observed spectrum by assuming that a hypothetical electrically charged oscillator in a cavity that contained black body radiation could only change its energy in a minimal increment, E, that was proportional to the frequency of its associated electromagnetic wave.
Not unreasonably, however, we find that individual photon energies do indeed fit exactly to Planck's assumption.
Photons can be generated by accelerating charged particles (including electrons, or protons, or muons, or alpha particles etc.)
Of course, it is also possible for electrons to be promoted by light. This is how pigments appear to be colored, and how fluorescent dyes glow.
PS I like the cheek of the Harvard paper on "measuring the wavelength of light with a ruler". When you have worked your way through the geometrical optics theory, you get to the experimental setup where the critical element is a 1/64 inch ruler, and the everyday bit of kit you just happen to have in the kitchen drawer is a coherent monochromatic laser. My next paper will be entitled "crossing the Irish Sea with a magnetised sewing needle". You float the needle carefully on the meniscus of a glass of water (it's a good trick - one method is to float it initially on a cigarette paper, which gradually sinks as it gets wet) then start up your airplane and just fly perpendicular to the needle.... Try this at home, with any steel needle.....
A LED is not a laser
a LED or similar single spectral line.
I would expect (accelerating) charged particles to be absorbing photons.
Presumably light of the exact wavelength needed to make the electron "leap".
What is the wavelength relationship (if any) between an emitted photon and the emitting particle?
It seems to me emitting of photons of an accelerating particle contradicts relativity.
Quote from: chiralSPO on 24/01/2019 03:41:38Photons can be generated by accelerating charged particles (including electrons, or protons, or muons, or alpha particles etc.)What of two electrons that are moving at the same speed and are then accelerated at the same rate (i.e. they are stationary with respect to one another), do they emit photons? It seems to me emitting of photons of an accelerating particle contradicts relativity.
Quote from: alancalverd on Yesterday at 13:58:26 a LED or similar single spectral line. And LEDs don't give single spectral lines, but lasers (nearly) do.