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IOW Heisenberg uncertainty is irrelevant?
Or are they like pigs?
"John S. Denker" wrote:
> At 02:48 PM 5/11/00 -0400, GARY HEMMINGER wrote:
> >The question has arisen in one of my classes - are continuous
> >spectra truly continuous?
>
> Then at 11:12 PM 5/11/00 -0500, Ludwik Kowalski wrote:
> >
> >I think the spectra are really continous. Why do you doubt?
>
> I agree with Ludwik.
>
> To be even more explicit: All spectra are continuous under all
> circumstances. The things we call "lines" are resonances. They have a Q
> which might be large but cannot be infinite. Off-peak transitions are
> always possible.
>
> To continue, at 02:48 PM 5/11/00 -0400, GARY HEMMINGER wrote:
> >
> > I'm wondering about this from both a
> >theoretical and practical point of view.
>
> OK....
>
> > Does theory say that there
> >are an infinite number of wavelengths emitted in the visible range for
> >example by a black body,
>
> Yes.
>
> Nitpickers note that "infinite" means the usual thing, namely that there is
> no meaningful finite upper bound.
>
> > Is the limited resolution of our equipment an issue?
>
> It doesn't change the underlying physics.
>
> OTOH suppose the frequency resolution is poor and the noise floor is high.
> Then a Q of 1000 will be indistinguishable from a Q of ten zillion. The
> center of the resonance can't be resolved and the "wings" of the resonance
> are lost in the noise. Such an instrument might fool you into not caring
> about the off-peak behavior of your resonances.