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Stavros Kiri
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Drakkith! ..., I thought you knew? ...Drakkith said:
Today I Learned
- Thread starter Greg Bernhardt
- Start date
In summary: Today I learned that Lagrange was Italian and that he lamented the execution of Lavoisier in France during the French Revolution with the quote:"It took them only an instant to cut off this head and a hundred years might not suffice to reproduce it's...brains."
- #2,872
Drakkith
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Stavros Kiri said:
Nope!
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Stavros Kiri
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Well, now you know!Drakkith said:
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Klystron
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TIL... or realized that what seems like an advantage in one physics application can be a disadvantage to another. Specifically, I like the narrow bandwidth inherent in klystron designs centered around a particular wavelength, given the tendency of individual tubes to vary.
What I learned or realized: many physics labs require large bandwidth RF sources. Makes sense. Now I understand some of the frustration experienced by tube manufacturers such as Varian Associates. Radar and communication types demand tight bandwidths with minimal frequency drift while laboratories want a single (expensive) device to produce as much spectrum as possible to power a large variety of experiments.
What I learned or realized: many physics labs require large bandwidth RF sources. Makes sense. Now I understand some of the frustration experienced by tube manufacturers such as Varian Associates. Radar and communication types demand tight bandwidths with minimal frequency drift while laboratories want a single (expensive) device to produce as much spectrum as possible to power a large variety of experiments.
- #2,875
BillTre
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TIl that here is an on-line database of different periodic tables.
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Ibix
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Loving the Periodic Table of Rejected Elements. Includes elements such as Asinine, Imodium, Celinedion and Belgium.BillTre said:
- #2,877
Stavros Kiri
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Mom! Mom! I want my own element too! ...Ibix said:
- #2,878
Klystron
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Today I learned connections between double Mersenne and Catalan numbers. Given my memory seems sluggish today, I had to backtrack wikipedia to remember how to form a Mersenne prime, a function I learned when I was 8 years old. Ain't age grand?
Still, once the combinatorics began to flow, the rough corners sloughed off and the wheels began to spin. Another problem I notice aside from remembering formulae is that very large integers lose individuality. Like black cats crawling in a coal mine compared to sunlit birds flitting about an aviary.
Still, once the combinatorics began to flow, the rough corners sloughed off and the wheels began to spin. Another problem I notice aside from remembering formulae is that very large integers lose individuality. Like black cats crawling in a coal mine compared to sunlit birds flitting about an aviary.
- #2,879
mfb
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You could share what you learned! The Catalan–Mersenne number conjecture, I guess.
- #2,880
Klystron
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Where studying the MC conjecture took me today. To begin near the end:mfb said:
In the set of positive integers > 5 there are no odd perfect numbers at least lower than 264 and probably for the entire set. Unproven but logical conjecture?
The search for new prime numbers using very large powers of 2 leads to and is very closely coupled to finding the next Mersenne prime. IOW it is computationally more efficient to calculate large powers of 2 and subtract 1 and then test the result for primality; i.e., show no factors other than 1 and the number, than it is to employ sieve algorithms with or without prior factorization.
Or in simpler terms: look for new primes among large Mersenne numbers (1 less than large power of 2) 2n-1.
I am predisposed to look for twin primes but have not connected double-Mersenne numbers to that quest (if there is any known relation).
I was distracted/diverted from studying the MC conjecture by the set of perfect numbers. Unless I am being fooled by the (humorous) Strong Law of Small Numbers, perfect number 28 is particularly useful in certain iterative applications. Most likely any connection to Lunar cycles is arbitrary and pre-scientific but its relation to biology, specifically perception, might be profound.
Need to think about what I read today and will relate better information tomorrow. Thanks.
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- #2,881
OmCheeto
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"The Netherlands has become the world’s second largest food exporter, while reducing water usage by 90% and nearly eradicating the use of pesticides"
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And the bad news is that their vegetables are indistinguishable from water. Monocultures, glass houses wherever you look, and no diversion. As long as we do not cultivate old breads and seeds we play a very risky game.OmCheeto said:
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mfb
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*breeds
I prefer vegetables with maybe not optimal taste over non-sustainable approaches.
I prefer vegetables with maybe not optimal taste over non-sustainable approaches.
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The neglect of old animal races and old varieties of fruits and vegetables is risky, see the bananas.mfb said:
And no, I prefer peppers, tomatoes and strawberries which do not taste like watermelons.
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mfb
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I mainly prefer things to exist in the first place. With business as usual we will have a very bad time. If tomatoes tasting like watermelons is what we need to keep Earth hospitable and food available in the future: Count me in.
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OmCheeto
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I also learned that one quarter of the Netherlands would be part of the sea, if not for humans.
[ref: NASA]
[ref: NASA]
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nsaspook
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Tom.G
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Hmm... awaiting results for the female protuberances. 
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OCR
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One of the preliminary researchers is still in the process of taking measurements. . .Tom.G said:
Please stand by. . .
.
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OmCheeto
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Just make sure they read the fine print; "Secondly, it is known that genital asymmetry exists at the level of testicular volume as well, with the left testicle being 7–10% smaller than the right testicle based on post mortem measurements"Tom.G said:Hmm... awaiting results for the female protuberances.
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Stavros Kiri
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TIL (or actually TIR [R=Realized], a few days ago ...) that the ISS is the only actual Space Station currently in orbit (ever since China's latest one Tiangong-2 was deorbited on 19 July 2019 [i.e. a couple of months ago]).
- #2,892
BWV
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If you enter this in google translate it causes a fatal error:
Wenn ist das Nunstück git und Slotermeyer? Ja! Beiherhund das Oder die Flipperwaldt gersput!
Wenn ist das Nunstück git und Slotermeyer? Ja! Beiherhund das Oder die Flipperwaldt gersput!
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TIL that there are actually pink elephants, no joke.
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mfb
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China plans to change this again in 2020 with the launch of the core module of their modular space station.Stavros Kiri said:
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Stavros Kiri
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Why would I want to do that?BWV said:
Sounds good to me! ...fresh_42 said:
They had said between 2019 and 2022. Any idea when in 2020 it is beginning?mfb said:
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Ibix
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Don't even read it if you speak German! One of the translators saw two words and was hospitalized for three weeks...Stavros Kiri said:
(Alternatively, google Monty Python Killer Joke)
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Stavros Kiri
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Lol ...Ibix said:
Basically [ignoring German vs English + nonsense/gibberish words/details]:
"My dog has no nose."
"How does he smell?"
"Terrible."
(+ seen in Lame Jokes, I think ...)
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- #2,898
Ibix
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No, that's the best German joke pre-war (or so the subtitles say - I gather the accompanying film was from Leni Riefenstahl's propaganda film of some turgid Nuremberg rally speech). The actual killer joke is never read out loud in English (the implication being that you'd be killed if it were). We do hear the "German translation" which is the vaguely German sounding gibberish BWV posted.Stavros Kiri said:
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Let me put it this way:Stavros Kiri said:
I recently made a joke about American (writing even the most obvious things in instruction manuals) and Chinese (eating everything) stereotypes. Another mentor complained and requested to remove it. Looks as if those standards do not apply to German stereotypes! And this was neither the first nor will it be the last case!
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Stavros Kiri
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That's not what I meant. It seems there was a typo in my post. I just edited (see last sentence) ...fresh_42 said:
[I just implied that Germans do actually survive the joke ...
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It was bad. Too bad to even answer. The "ü" was the closests it came to real German.
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Stavros Kiri
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Point taken. And I think the whole "funniest joke issue" is exaggerated. But my comment meant no offense to anyone [it was just humorous] , I hope you realize that.fresh_42 said:
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Sure. I was simply angry that joking about things put in the microwave as an American stereotype was criticízed while joking about sausages or language are not! Some people judge things very differently depending by whom it was said!
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Stavros Kiri
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Sometimes it happens. I try to be objective and impartial as well.fresh_42 said:
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