fflo: (dork L)
fflo ([personal profile] fflo) wrote2005-03-01 02:41 pm

Always remember & never forget . . .

... the Fermi Golden Rule:

$$B(\omega,v-v_*)=\frac{1}{8\pi^2}|\omega\cdot(v-v_*)||{\widehat \phi}
((\omega\cdot(v-v_*))\omega)|^2$$

---you know, where the hat $\sphat$ denotes the Fourier transform and $\phi$ is a two-body interaction potential.

[identity profile] peteralway.livejournal.com 2005-03-01 07:58 pm (UTC)(link)
(raises hand) Ooh! Ooh! I used to understand Fourier transforms! Used them to quantify the sphericity of microscopic H-bombs. Before I was paid not to. And ultimately not paid not to.

[identity profile] fflo.livejournal.com 2005-03-01 08:34 pm (UTC)(link)
What a coincidence: I'm also not being paid not to study them!

[identity profile] peteralway.livejournal.com 2005-03-01 09:22 pm (UTC)(link)
As much as I am rusty, I do recall a certain beauty to Fourier transforms. Both in what they represent in terms of spectrum, and how you could multiply something by a sine wave, and it would come out to zero, on average, if there were no correllation, and come out to something if there were a correllation. A lot of advanced math made me want to crawl into a cave, but Fourier was simple and beautiful. I like the way your ear does it mechanically and instictively to allow you to percieve music.

Of course, all the other stuff in your post was complete gibberish to me.
paperkingdoms: (Default)

[personal profile] paperkingdoms 2005-03-01 08:32 pm (UTC)(link)
Fourier transforms have unexpectedly become one of my favorites this semester. It gets really fun when you get to stack up the hats: a ^ on top of a v on top of a ~ for example [which popped up in class recently].

[identity profile] fflo.livejournal.com 2005-03-01 08:35 pm (UTC)(link)
Well, I don't understand the math, but I can get into such flukes of notation, that's for sure.
paperkingdoms: (Default)

[personal profile] paperkingdoms 2005-03-01 08:37 pm (UTC)(link)
Oh, at least a third of my enjoyment of Fourier transforms is typographical. [the upside down hat is undoing the Fourier transform.] I think part fun of math is the bizarre lengths we go through for precise notation [your supscripts have subscripts *and* superscripts??].

[identity profile] elmur-fudd.livejournal.com 2005-03-01 09:06 pm (UTC)(link)
I think you just broke me.

[identity profile] fflo.livejournal.com 2005-03-02 01:51 am (UTC)(link)
Broke you of what? hahhahahhaaahahahhaaa
groovesinorbit: (Default)

[personal profile] groovesinorbit 2005-03-02 01:02 am (UTC)(link)
Hey, I've heard of Fermi! I'm also working on an alum whose last name is Fourier. Your transforms are making my searching for him kind of a pain.

[identity profile] lovelikeyeast.livejournal.com 2005-03-02 04:42 am (UTC)(link)
Sometimes I just don't understand you, Fflo.

On the other hand, it looks good.

[identity profile] fflo.livejournal.com 2005-03-02 04:33 pm (UTC)(link)
Speaking of looking good, I just clicked on the nolose site! WOW! Rock and ROLL, LLY!