Essay talk:ADK's Occasional Guide To Quantum Mechanics

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That's fun and informative. What you've written so far was nearly all covered in my first years of college (before I decided I'd have an easier time building planes), so I'm not the right guy to decide if it can be helpful to a complete newbie to the field, but it worked very well in making my old memories re-surface.

I'm waiting impatiently for the rest and the more complex stuff.

Here are a few comments so far:

  • First things first - The electron: typo warning: quiet -> quite
  • Particle-wave duality: "A golf ball will have a wavelike quality to it, just that it's too small and too massive for that wavelength to be even meaningful." Can be read like it's the golf ball that's too small. I'd write something like "A golf ball will have a wavelike quality to it, just that its wavelength is too small compared to the massive ball for that wavelength to be even meaningful."
  • Particle-wave duality - The double-slit: an image of the interference pattern would be nice to show.
  • Other important factors - Building a wave(function): "a wave needs to have certain properties for it to be a good that works in the real world" isn't there a "wave"missing? Like in "a wave needs to have certain properties for it to be a good wave that works in the real world"? Or do I misunderstand?

dx (talk) 22:40, 9 March 2012 (UTC)

Cheers for the pointers, I'll review it ASAP. The aim is to get that first-year type stuff down, then I might move onto more complicated stuff and maybe, just maybe, write down an equation or two - but I'm taking the Brief History of Time maxim that every equation halves sales, so I don't know! Scarlet A.pngpathetic 23:09, 9 March 2012 (UTC)
To be honest, though, I was originally trying to distill quantum mechanics into the smallest possible volume. It turns out that all that stuff I've learned over nearly a decade takes up a considerable amount of room. I wasn't quite fully aware of it until I actually wrote it down, so at least this has been useful to me. Maybe I might be able to crunch it down even further, but I think that might take a lot more effort. Scarlet A.pngd hominem 01:53, 10 March 2012 (UTC)


Looks interesting, but what source or sources is it based on?--Baloney Detection (talk) 17:43, 18 July 2012 (UTC)

My job. Scarlet A.pngsshole 18:58, 18 July 2012 (UTC)
Care to elaborate?--Baloney Detection (talk) 19:07, 18 July 2012 (UTC)


I have a comment on the following paragraph:

"Essentially, an atom obeying simple classical mechanics, wouldn't be stable. Recall that opposite charges attract; then how do the electrons not just go crashing into the nucleus? Classical mechanics posit that it should, and it was quantum theory that stopped this from happening in our models, giving us the best explanation of nearly all the properties of the atom."

Under this argument, planets would just crash into the Sun. Classical mechanics does predict stable orbits for non charged objects (The inwards gravitational/electrical force would balance the outwards centripetal force). The problem is that the electron, being a charged particle, would emit radiation when moving in circles, hence loosing energy, and spiralling into the nucleus. --Tlaloc (talk) 19:12, 6 June 2014 (UTC)

This is correct. Radiative losses would ensure that electrons could not stay in any stable orbit without a constant influx of energy. - Grant (talk) 19:29, 6 June 2014 (UTC)
I'm not sure how that argument applies to planets since we're talking a) different forces and b) completely different scales. But it's easily changed to something more detailed. Scarlet A.pngDon't click here 22:14, 6 June 2014 (UTC)
It applies. Whether gravitational or electrostatic, it's still a centripetal force that can be balanced. The completely different scale matters not from a classical mechanics perspective, which is the assumption we are working from. Now the whole thing with the electron radiating energy comes into play, suggesting that classical physics provides an inadequate description here. Nullahnung (talk) 23:01, 6 June 2014 (UTC)