Today I Learned

  • Thread starter Greg Bernhardt
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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."
  • #3,991
gmax137 said:
I have seen them "u-toobing" how to do some of the work. If my clients caught me doing that I'd be fired.
Every software developer ever:
1633039590706.png
 
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  • #3,993
TIL

In Chinese tradition, higher status for men was signified by having several young female partners or concubines. A ring denies that status. For this reason, many modern Chinese men do not wear a wedding ring. Diamonds and two-partner wedding rings are advertised in modern China.
https://en.wikipedia.org/wiki/Visua... higher status,are advertised in modern China.
 
  • #3,994
RIL that Lucille Ball allegedly helped catch Japanese spies during WWII. She started picking up Morse code through the fillings in her teeth while driving home.

How Lucille Ball Heard Spies Through Her Dental Fillings

In 1974 Lucille Ball told TV host Dick Cavett that during World War II she picked up radio broadcasts through her dental fillings as she was driving home from the MGM studios through Coldwater Canyon. The phenomena subsided as she continued driving. When it happened again a week later she told MGM security because the signals seemed to be Morse code. She stated that the FBI located the source of the signals, an underground Japanese radio station.
https://www.bradfordfamilydentist.ca/lucille-ball-heard-spies-dental-fillings/
 
  • #3,995
jack action said:
How cute that Youtube thinks of itself as a reliable source of information.
Delusions of Grandeur, for sure!
 
  • #3,996
I learned that the rickshaw was invented in Tokyo in 1869.

Yesterday I learned that cosplay was invented in Los Angeles in 1936. It stayed small time until 1984 when a visiting Japanese writer discovered it.
 
  • #3,997
BillTre said:
TIL that youtube is going to block all anti-vax materials on their site.
https://finance.yahoo.com/news/1-youtube-blocks-anti-vaccine-134911074.html
I am not sure how that would work

All the anti vax stuff I have read has mainly been following an update from Boris Johnson or Professor Whitty

So those videos are not anti vax themselves but the responses to it are.
Will they be removing individual posts too? Via an algorithm?
Also, is this needed?

Will this not give them victim hood/oppressed status? Justify the clams of cover up/conspiracy?

Anyone who goes on youtube and takes in the conspiracy as Gospel, was not paying attention in school
 
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  • #3,998
pinball1970 said:
I am not sure how that would work
They delete all the claims that the vaccine makes you magnetic, will kill your children, causes blood clots and death, makes you sterile, is loaded with government tracking devices, etc.
 
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  • #3,999
TIL how to wrap my long cables and ropes and extension cords so that they do not tangle and are super-easy to unfurl. Thank you @BillTre :smile:

BillTre said:
Here are a couple:


As you hang a new coil on one hand, alternate the way you rotate the other hand as you place the next coil in the hand holding the bundle other hand.

It reminds me of DNA supercoiling.
 
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  • #4,000
Che Guevara had Irish ancestry, visited Ireland, and the famous image of him was painted by an Irish artist.
 
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  • #4,001
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  • #4,002
I learned that those paintings of dogs playing poker date back to 1894.
 
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  • #4,003
Hornbein said:
I learned that those paintings of dogs playing poker date back to 1894.
That game has been going on for 889 dog years?
 
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  • #4,004
TIL that I got a raise. :cool:
 
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  • #4,005
TIL that contrary to very widespread statements in woodworking, end to end glue joints are NOT weaker than end to side or even side to side but are in fact stronger. That is not to say that they are good joinery for structural support, just that all other things considered they are the strongest.

 
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  • #4,006
phinds said:
TIL that contrary to very widespread statements in woodworking, end to end glue joints are NOT weaker than end to side or even side to side but are in fact stronger. That is not to say that they are good joinery for structural support, just that all other things considered they are the strongest.
Modern saws and glues have come a long way, baby; "fast-tacking" glues plus power miter saws have gone a long way toward eliminating/rounding some of the "knuckle-buster/scraper" woodwork around my house. Still got to do some thing with the sharp-cornered fireplace "mantle/millwork obscenity" the builder stuck us (literally) with, but getting there. Did a really nice bannister rail in the basement as an experiment/test of techniques.
 
  • #4,007
Today I discovered that ##e^{i\pi}\approx \pi^{ie}##.

More accurately, ##e^{i\pi}=-1##, while ##\pi^{ie}\simeq -0.9996 +i 0.03##.
 
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  • #4,008
Demystifier said:
Today I discovered that ##e^{i\pi}\approx \pi^{ie}##.

More accurately, ##e^{i\pi}=-1##, while ##\pi^{ie}\simeq -0.9996 +i 0.03##.
After playing, this is equivalent to
lnπ ≈ π/e or 1.145 ≈ 1.156
coolness lost :frown:
but
lnπ=ln(e(π/e))=1+ln(1 + (π/e-1))
and taking the first term of the taylor expansion gives lnπ ≈ π/e
coolness restored :wink:
 
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  • #4,010
Demystifier said:
Today I discovered that ##e^{i\pi}\approx \pi^{ie}##.

More accurately, ##e^{i\pi}=-1##, while ##\pi^{ie}\simeq -0.9996 +i 0.03##.
Where is etothepii when you need him?
 
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  • #4,013
https://www.bloomberg.com/news/arti...lost-entire-savings-during-covid?srnd=premium

For many Americans, Covid lockdowns—with nowhere to go and nothing to do—were a time to save. But for almost 20% of U.S. households, the pandemic wiped out their entire financial cushion, a poll released Tuesday finds.

The share of respondents who said they lost all their savings jumped to 30% for those making less than $50,000 a year, the poll from NPR, the Robert Wood Johnson Foundation and the Harvard T.H. Chan School of Public Health finds. Black and Latino households were also harder hit. The researchers surveyed a nationally representative sample of 3,616 U.S. adults ages 18 or older.
 
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  • #4,014
There's a cool theorem I came across earlier, that if you draw any old closed, squiggly loop on the surface of a sphere, then the angle through which a vector rotates after being parallely transported around the loop equals the solid angle subtended by the loop. Have fun :)
 
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  • #4,015
phinds said:
TIL that contrary to very widespread statements in woodworking, end to end glue joints are NOT weaker than end to side or even side to side but are in fact stronger. That is not to say that they are good joinery for structural support, just that all other things considered they are the strongest.


This is pretty surprising to me. I've made such joints when I was a beginner woodworker only for them to fail incredibly easily. I've never had a side to side joint break ever, although I do know the wood is weak in that direction.

Also, I wonder about longevity? The end to end joint is highly inflexible. PVA glue joints get more brittle over time. Wood also breaths through the end grain, and swells perpendicular to the end grain. If the wood is side to end, then you have two faces of wood swelling in different directions and at different rates. The wood swelling is a powerful force that can't be suppressed easily.

My personal opinion is myth not busted.
 
  • #4,016
Jarvis323 said:
incredibly easily
Incredibly easily compared to a strip of wood without a cross-cut join. The referenced article agrees with that much. Lengthwise wood fibers are stronger than glue. By a factor of four or so (from memory of viewing the video).

Not incredibly easily compared to a strip of wood without a ripped join. The glue is stronger than the lignin.

One needs to be clear on what is being compared. Ripped glue joint to cross-cut glue joint? Or uncut wood to cross-cut then glued wood?

Indeed, one does not construct a twelve foot beam using a butt joint between two six foot beams.
 
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  • #4,017
  • #4,018
Reading Jonathan Littell’s novel the Kindly Ones, learned about the Bergjuden

https://en.wikipedia.org/wiki/Mountain_Jews#Early_history

The Mountain Jews, or Jews of the Caucasus, have inhabited the Caucasussince the fifth century CE. Being the descendants of the Persian Jews of Iran, their migration from Persia proper to the Caucasus took place in the Sasanian era (224-651).[7] It is believed that they had arrived in Persia, from Ancient Israel, as early as the 8th century BCE[16] Other sources, attest that mountain Jews were present in the region of Azerbaijan, at least since 457 BCE[17][18] However, the Mountain Jews only took shape as a community after Qajar Iran ceded the areas in which they lived to the Russian Empireper the Treaty of Gulistan of 1813.[9]

With the help of their Kabardian neighbors, Mountain Jews of Nalchik convinced the local German authorities that they were Tats, the native people similar to other Caucasus Mountain peoples, not related to the ethnic Jews, who merely adopted Judaism.[28] The annihilation of the Mountain Jews was suspended, contingent on racial investigation.[26] Although the Nazis watched the village carefully, Rabbi Nachamil ben Hizkiyahu hid Sefer Torahs by burying them in a fake burial ceremony.[29] The city was liberated a few months later.
 
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  • #4,020
BWV said:
Mountain peoples, not related to the ethnic Jews, who merely adopted Judaism
I actually know a couple of novels that feature the Khazar Khanate.
Dictionary of the Khazars by Pavic (beautiful language)
Gentlemen of the Road by Chabon (bought a couple of weeks ago, still on nightstand)
They also show up in Roman (Byzantine period) history.

On a related topic, I read this in a history a couple of years ago and love how it plays on our modern perceptions.

“Yusuf As’ar Yath’ar, an Arab king celebrated for his long hair, his piety and his utter ruthlessness, had been brought to defeat. Leaving the reek of the battlefield, he rode his blood-flecked white charger down to the very edge of the Red Sea. Behind him, he knew, Christian outliers would already be advancing against his palace—to seize his treasury, to capture his queen. Certainly, his conquerors had no cause to show him mercy. Few were more notorious among the Christians than Yusuf. Two years previously, looking to secure the south-west of Arabia for his own faith, he had captured their regional stronghold of Najran. What had happened next was a matter of shock and horror to Christians far beyond the limits of Himyar, the kingdom on the Red Sea that Yusuf had ruled, on and off, for just under a decade. The local church, with the bishop and a great multitude of his followers locked inside, had been put to the torch. A group of virgins, hurrying to join them, had hurled themselves on to the flames, crying defiantly as they did so how sweet it was to breathe in “the scent of burning priests!” Another woman, “whose face no one had ever seen outside the door of her house and who
had never walked during the day in the city,” had torn off her headscarf, the better to reproach the king. Yusuf, in his fury, had ordered her daughter and granddaughter killed before her, their blood poured down her throat, and then her own head to be sent flying.
Martyrdoms such as these, fêted though they were by the Church, could not readily be forgiven. A great army, crossing from the Christian kingdom of Ethiopia, had duly landed in Himyar. The defenders had been cornered, engaged and routed. Now, with the shallows of the Red Sea lapping at his horse’s hooves, Yusuf had come to the end of the road. Not all his obedience to the laws granted to God’s chosen prophet had been sufficient to save him from ruin. Slowly, he urged his horse forwards, breasting the water, until at last, weighed down by his armour, he disappeared beneath the waves. So perished Yusuf As’ar Yath’ar: the last Jewish king ever to rule in Arabia.

from Holland “In the Shadow of the Sword”
This event occurred early 6th century. Himyar was then located in what is now essentially Yemen.
After reading this, I learned that there are several non-ethnic Jewish groups that adopted Judaism in history.
 
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  • #4,021
Jarvis323 said:
This is pretty surprising to me. I've made such joints when I was a beginner woodworker only for them to fail incredibly easily.
I suspect you're comparing apples to oranges. The video is VERY specific about exactly what conditions are being tested and I doubt those were the conditions you are talking about. See my comments about leverage, for example.
 
  • #4,022
 
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  • #4,023
Today I learned that the actor who played Nigel Tufnel in Spinal Tap is the 5th Baron Haden-Guest. His wife Jamie Lee Curtis is Lady Haden-Guest.
 
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  • #4,024
Today I learned that illegal immigrants from the United States created the short-lived country of Texas.
 
  • #4,025
Hornbein said:
Today I learned that illegal immigrants from the United States created the short-lived country of Texas.
They did something similar in California called the Bear Flag Revolt and it's where the bear on the state flag comes from.
 
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