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PM 2Ring
19:00
Yeah, I just need to write a few more answers. But that entails finding decent questions that I can answer. ;)
enumaris
lol they put my salutation as my title
so my name is displayed XXXXX XXXX Dr.
rather than Dr. XXXXX XXXX
hmmm
Anonymous
@rob Yeah. I was mainly talking about 3k-ers active in chat though.
enumaris
oh they don't have Dr. as salutation, only as title, so I guess that's just the way things are formatted...
rob
@Blue Yes, that population is much smaller.
Emilio Pisanty
19:21
damn
Nasa confirms Mars rover Opportunity is dead
Loong
DanielSank
I'm trying to write up a pedagogical note on coupled oscillations.
Given two coupled oscillators with frequencies $\omega_1$ and $\omega_2$, we can arrive at the following equation:
enumaris
which iphone should I get for my company phone
o.O
is the 8 plus the newest line
rob
@EmilioPisanty What a shame that Opportunity only survived for fifteen years out of its planned ninety-day mission. A great loss and an astounding success. Still too soon.
DanielSank
$$\left( \begin{array}{c} x_1 \\ x_2 \end{array} \right) = \left( \begin{array}{cc} -(1+\epsilon_1)/\omega_1^2 & \epsilon_1/\omega_1^2 \\ \epsilon_2/\omega_2^2 & -(1 + \epsilon_2)/\omega_2^2 \end{array} \right) \left( \begin{array}{c} \ddot{x}_2 \\ \ddot{x}_2 \end{array} \right)$$
OH SNAP FIRST TRY I AM A MASTER OF MATHJAX
2
Here $\epsilon_1$ and $\epsilon_2$ are both much less than 1.
Given eigenvalues $\lambda_1$ and $\lambda_2$ of that matrix, the normal mode frequencies are $\sqrt{-1 / \lambda}$.
Emilio Pisanty
19:31
@rob Sol 5352 sounds even better
@DanielSank ahem
you were saying?
DanielSank
@EmilioPisanty >.>
PM 2Ring
Mary had a little lambda
DanielSank
Ok so now the question is this: can we come up with a
nice
expression for $\lambda$?
I can get half-decent expressions by using the $\epsilon \ll 1$ approximation liberally.
I don't suppose anyone else would like to have a go?
Emilio Pisanty
@DanielSank wait, why is that not hermitian?
shouldn't it be?
DanielSank
@EmilioPisanty No.
@EmilioPisanty Because the two oscillators aren't identical.
Emilio Pisanty
19:33
huh
still though
there should be
some
sense of hermiticity there, right?
DanielSank
But this is a very good question. I think the problem may simplify considerably if we rescale the variables to
make
it Hermitian.
Emilio Pisanty
$\uparrow$
DanielSank
@EmilioPisanty I think it is {Hermitian up to rescaling of stuff}, and actually that's exactly where I would like some help.
Are there new variables we should use to achieve hermitian-ness?
Emilio Pisanty
@DanielSank would love to dig into it, but I'm rushing to send off a paper asap
DanielSank
@EmilioPisanty Ok. Good luck.
Emilio Pisanty
19:35
@DanielSank indeed
Glossy Number One has said that they're not keen enough on our stuff
they've referred us down to Glossy Number Two
DanielSank
Who is GNO?
Ah, the magazine.
Bah, publish in a journal. Forget the magazines.
Emilio Pisanty
@DanielSank it is a journal
it just has a glossy cover
DanielSank
I see.
2 hours later…
PM 2Ring
22:00
This perpetual motion Q just got bumped.
physics.stackexchange.com/questions/106742/…
Anonymous
Unrelated: commenting on meta seems to be a trap. Replying to comments is just so tempting. Gotta self-control! :P
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