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12:45 AM
In "Cargo Cult Science", Feynman talks about the slow drift of the measured value of "e" from Millikan's incorrect value to the accepted value.
Anyone know of a nice (and copyright kosher) figure showing the time series with error bars? Or a convenient source for the raw data---I have plotting software, after all.
 
IDK about for e, but I did one some time ago for c
 
 
2 hours later…
user54412
3:10 AM
@dmckee Alas, all I've been able to find is A selected history of expectation bias in physics, which does this for a CP violation parameter and for c, while PDG has this pdf that does it for some other (generally more esoteric) parameters.
 
user54412
Also, in the second link, it's not clear how much year-to-year consistency is due to cargo cult vs. no one doing new experiments
 
user54412
3:55 AM
@dmckee Actually done for e (and m_e, h, alpha^-1, and N_A) here but the data is somewhat sparse, and only covers about 1950-1975
 
4:49 AM
@ChrisWhite Nice. Thanks for all those links. I'll have to look at them when I have my AAPT membership info handy...
I think the neutron lifetime and the Lambda mass values are very interesting from the PDF graphs. And a couple of the exotic ones, but they won't be very appealing to undergraduate students.
 
 
3 hours later…
8:16 AM
solid state physics
that was such a sick course in my program. Taught by a pretty 'important' guy (by Dutch standards) who was a mix of derogatory, arrogant, incredibly smart, racist and old. He taught the course 'for fun' although he was technically retired, teaching from his own syllabus (typed up in Word (!) )
 
 
4 hours later…
12:18 PM
I think 60% of the class dropped out half-way because he either insulted them, or they were deterred by his frequent and difficult problem sets and exams
 
12:59 PM
@Danu Hey :D
 
@Danu A course taught by an emeritus is usually either very good or very bad. I've been lucky enough to draw 'very good' three times out of three.
You get the good case reliably from guys teaching their passion to people who have sufficient preparation (because they wrote the prerequisites) and the desire (because it is not required for graduation).
Hmmm ... the "guys" above might carry too much implication of gender. In my case they were all men, but I don't mean to exclude women.
 
1:25 PM
Hey phonon!
@dmckee it's interesting in this case
In retrospect he did teach us a lot of valuable stuff
but he was also a huge ... about it
 
@Danu some chess? I got a break ^^
 
@Phonon I'm in a game atm, but afterwards sure!
 
@Danu sure send me a challenge whenever, logged in
 
 
1 hour later…
2:47 PM
Once again, I feel that Stack Exchange is missing a critical feature: the you're being a twit button.
 
Haha
With regards to what now?
 
Or maybe that's just a function of it's being (notional) September.
@KyleKanos Processing flags. Certain users presume to question the statements of others on the basis of utter, blinkard, philistine, pig-ignorance.
 
Interesting.
 
@dmckee someone is nit-picking again?
Also, is there a significant increase in traffic in september usually?
 
2:53 PM
School "starts" in September
Most American colleges start in August though
 
Right
Germany uni only starts in October!
 
 
2 hours later…
4:33 PM
@ACuriousMind haha did you see this one? :) physics.stackexchange.com/questions/132114/…
 
@Phonon I didn't read more than the title before. I...don't like these hypothetical questions very much, but this one's at least sort of answerable, it seems. I like to keep superheroes and physics seperate in my head though, so that I can enjoy both of them ;)
 
@ACuriousMind haha yeah, Jim took it seriously and wrote a nice answer :D
 
I took it seriously too
 
I skimmed it (and at least I now know the frame rate of human sight), but I got to run know - real life has (pleasantly) become a bit more real these last days for me (which is why there's not much activity from me ATM) ;)
 
Is my sarcasm detector working correctly:
@KyleKanos, wow, that was harsh. It completely obliterated any argumemts and the actual topic of this discussion (on this meta post). — Nikos M. 1 min ago
 
5:11 PM
@KyleKanos my sarcasm meter is reading 0 on that, but calibration is difficult
 
Is the scale 0 (no sarcasm) to 10 (sarcasm)?
 
I didn't really think about an upper bound, but I meant it to be a linear, positive scale
 
Ah
So that means you think it was a serious comment?
 
yes
the Internet is toneless, but looking at the rest of the recent comments by Nikos M., I don't see why it should be sarcastic
 
Hmm. I think I've seen sarcasm from him before, but it does seem a tad out of place there
 
5:55 PM
It's funny how early one can often tell which users will end up protesting action by high-rep users etc.
 
6:26 PM
@Danu I've never understood the internet mentality... "Hey, nice sandbox? Mind if I come and play with you? Wait, you're playing wrong and this isn't like my sandbox! Let's change it!"
5
 
I understand it all too well, haha, but I like that we try and resist it :)
 
Oh well. Everybody is a critic I guess
 
just some are more of a critic than others, and especially that tone that some use
 
Yeah, it's always the tone that gets me. We're not trying to persecute groups of people.
 
People love being a victim
...while maintaining a borderline rude attitude :)
 
6:35 PM
It is more funny when the premises are entirely incorrect
 
What really is at the essence of it is a sort of sense of entitlement, I think
 
Jim
6:51 PM
Wow, I'm getting so many downvotes for my answer to the superhuman speed question because people think limited exposure time is the same as speed
 
ouch, three is really a lot
 
Jim
lol, I'm thinking proportionally, 33% so far
 
funny, your point of the confined space is exactly what my kneejerk response was when reading the question (i.e. NO!)
ah, have my upvote :)
 
Jim
well, thanks. I was really just trying to complain because I've updated and tried to clarify 3 times and every time the up-votes on that one comment steadily rise. But thanks for the vote
nice to know the physics-knowers have my back
 
I think you and I came to the same conclusion (though my specification was in the comments)
If the motion is small, then it could be possible
But it's not feasible in the situation at hand
 
Jim
7:00 PM
@KyleKanos had to reread your answer just now. Realized you and I were addressing two distinct things. I was about pure visibility of the object, you seem to be talking about visibility of the motion
In which case, you got my +1
 
Yes, that is what I was going on about
 
7:21 PM
The answers to that question sort of rub me the wrong way, mostly because "frame rate" makes it sound like the eye is compiling an image for you every so many milliseconds. It helps that the photoreceptor response frequency is in there, but I would have liked to see more emphasis on calling it something like "effective frame rate". Haven't voted up or down yet, think I'm going to read over it again in a little bit to give myself a second opinion and try to decide which I think is clear+accurate.
 
Pfft, my answer is obviously the best :D
 
I didn't see it because I was scrolling the page too fast (see what I did there?).
 
LOL
 
Well, when you read it, you'll agree ;)
 
Jim
7:42 PM
@Kyle yeah, I didn't want to say just frame-rate, so I put in the quotes. I know it's not a true frame rate, but I hadn't thought of using the word "effective" until you mentioned it
 
 
1 hour later…
8:42 PM
hey guys, does anyone know what this detail in Sakurai's Modern QM means: (footnote) The astute reader, already familiar with wave mechanics, may point out that the completeness of eigenfunctions we use can be proved by applying Sturm-Liouville theory to the Schrodinger equation
I could ask it as a question
I'm sure Mr. Moretti would be happy to explain :D
(I have a vague idea of what S-L theory is from my course on diff. eqns., but not much)
ah, I think the comments here answer my question
 
user54412
9:45 PM
@Danu There are definitely subtleties though, once one has unbounded domains, and these are usually glossed over.
 
user54412
See the comments by Christopher Wong (who was a classmate of mine with whom I took my first QM course, where we even got the prof to admit the standard proofs are pretty flawed for ignoring this)
 
10:03 PM
Interesting
@ChrisWhite Interestingly, all the QM books I've read (just Griffiths and Sakurai) assume completeness!
after Dirac, who apparently took it as an axiom
 
@Danu any other interesting posts came about today?
 
I didnt find any that aroused my interest :(
 
ok :(
 
user54412
10:28 PM
@Danu As I age, what I find stranger and stranger is that all QM texts focus on infinite dimensional cases, when in simple finite-dimensional cases (1) the math is a lot simpler, requiring no lies to children and (2) every salient feature of QM (unitarity, collapse, superposition, non-commutativity of operators) is still present
 
I presume because one wants to talk about scattering and stuff like that
 
user54412
Hmm, I didn't see scattering until well into my second year of QM, but maybe that's because I wasn't taught by particle experimentalists
 

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