1,171 reputation
411
bio website marty-green.blogspot.com
location Canada
age
visits member for 3 years, 5 months
seen yesterday

Aug
29
comment How can I stand on the ground? EM or/and Pauli?
Yes, you're right about that. I think what I meant was that it's not exactly the same s-orbital as the hydrogen atom. It's a different shape, because the electrons push each other apart. But regardless, I'm still don't know why I'm the only guy who thinks Heisenberg is more important than Pauli when it comes to stopping us from falling through the floor.
Aug
27
comment How can blackbody radition be explained by quantization?
Yes, it is funny what you can learn when you apply the mathematics to a hypothetical case. I'm glad you agree.
Jul
15
comment How can molecule of a few angstroms absorb visible light of a few hundred nanometers?
The theoretical result whereby the absorption cross-section of a small classical antenna is on the order of the wavelength squared is a not-so-well-known classical result that nevertheless appears in such textbooks as Kraus (from the 1930's) and you can verify it on Wikipedia. It is normally derived by pure mathematics; however, on my website I give a physical picture of why it makes sense: see marty-green.blogspot.ca/2011/10/crystal-radio.html
Jul
15
comment How can molecule of a few angstroms absorb visible light of a few hundred nanometers?
I've wondered what might be possible with very small antennas using piezo-electrics, but not because of the dielectric constant. My thinking was that if the capacitive element had a mechanical oscillation in tune with the electrical frequency, you wouldn't need huge inductors to tune the antenna. But then I don't suppose it would have to be piezo-electric...just any old dielectric that was highly tuned to the right mechanical frequency could work. Maybe that's what they are doing with ceramic chips?
Jul
14
comment How can molecule of a few angstroms absorb visible light of a few hundred nanometers?
This is not a bad answer, but it is unnecessary to talk about "lossy" components in understanding the classical antenna. We can imagine everything made of superconducting wires; and then, as user21748 correctly notes, it is not so much the absorption cross-section which goes down as you make the antenna smaller, but the bandwidth. And to be technically correct, it is not exponential but cubic: that is, if you make your ideal lossless antenna half as big, your Q factor (wL/R) and with it your bandwidth goes by a factor of 8.
Jul
14
comment How can molecule of a few angstroms absorb visible light of a few hundred nanometers?
@leftaroundabout: Not unless you have a microphone that is super-sensitive to low B-flat but rejects low A and low B. Which is what the atom does.
Jul
14
comment How can molecule of a few angstroms absorb visible light of a few hundred nanometers?
I don't know anywhere you'll find the analysis except on my blog. I used to think that Jaynes and Scully "semi-classical" school represented my ideas, but it turns out they don't. Did you check out the link on Crystal Radio that I posted in my answer? I go into more detail on the comparision between the Copenhagen calculation and the semi-classical analysis in a series of articles starting with this one: marty-green.blogspot.ca/2012/02/…
Jul
14
comment How can molecule of a few angstroms absorb visible light of a few hundred nanometers?
You made that animation? That is excellent and really needed on the internet. I used to be able to find some pretty good three-dimensional animations of the hydrogen orbitals in superposition, but I can't find them anymore. So your animation, which clearly shows the basic idea, is really useful.
Jun
14
comment Nodes in wave functions outside of the classical turning point
Yeah, it's a little hard to find because it's not listed as the Potential Well in the Table of Contents. Section 16-6, "Quantized Energy Levels".
Jun
11
comment What is predicted to happen for electron beams in the Stern-Gerlach experiment?
But I didn't make any claims about the results of numerical experiments.
Jun
11
comment What is predicted to happen for electron beams in the Stern-Gerlach experiment?
You didn't read my blog posting, did you?
Jun
11
comment What is predicted to happen for electron beams in the Stern-Gerlach experiment?
Okay, you can get two dots if you use a numerical computation. I meant you can't get two dots if you try to do the actual experiment.
Jun
2
comment Can nuclear transmutation be observed in real time?
You didn't read my essay, did you?
Jun
2
comment Can nuclear transmutation be observed in real time?
People talk about doing the double slit experiment "one electron at a time", but all they mean is that the beam intensity is so low that the detection events are far apart. There is still no machine that shoots out single electrons at will. I talk about this in an essay I posted a few years ago on the FQXI site: "There Are No Pea-Shooters For Photons". fqxi.org/data/essay-contest-files/…
May
27
comment Intuition/derivation behind the probability current definition
I pity the fool who thinks he can out-umlaut the Germans.
May
25
comment Interesting relationship between diffraction and Heisenberg's Uncertainty Principle?
you are so right. I don't know what their problem is.
May
13
comment Do ionisation of atoms release photons?
Actually, if hydrogen is a typical example, the UV transitions are the ones that end up in the ground state.
Mar
21
comment When combining three spin $\frac{1}{2}$ particles what are the corresponding states?
I didn't read your question carefully when I posted my answer (thanks for the upvote) but now I notice you list five states, including one with m=0. I'm quite sure that's wrong...there's always going to be an odd half-spin left over with three electrons.
Mar
10
comment What is the Bremsstrahlung or dipole radiation mechanism involved in the emission of radiation by the rotating or moving charge?
Of course you're right...my bad.
Feb
8
comment Which electron gets which energy level?
We can count the total number of electrons in an atom; but we can't EXACTLY count how many are an "orbital", because the idea of discrete orbitals is only a good approximation that helps us do chemistry.There really is just one big wave function for all the electrons in the atom.The common explanation of the Pauli principle makes it look like we just put two electrons in each orbital, but the correct technical definition of the Pauli principle is that if we reverse any two "electrons" the 3n-dimensional wave function, we get the same wave function back again except with a negative sign.