Today I Learned

[hutchphd]

Che Guevara had Irish ancestry, visited Ireland, and the famous image of him was painted by an Irish artist.

Ya got to love the CIA. Please note the condescension of the last paragraph of this dossier.
https://pbs.twimg.com/media/EeVvhhyXYAMGThm?format=jpg&name=large

 

[Hornbein]

I learned that those paintings of dogs playing poker date back to 1894.

 

[jbriggs444]

I learned that those paintings of dogs playing poker date back to 1894.

That game has been going on for 889 dog years?

 

[Ivan Seeking]

TIL that I got a raise.

 

[phinds]

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.

 

[Bystander]

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.

 

[Demystifier]

Today I discovered that $e^{i\pi}\approx \pi^{ie}$.

More accurately, $e^{i\pi}=-1$, while $\pi^{ie}\simeq -0.9996 +i 0.03$.

 

[Frabjous]

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
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

 

[Frabjous]

I learned that those paintings of dogs playing poker date back to 1894.

Here’s an art history podcast episode inspired by Coolidge’s paintings.
http://www.thelonelypalette.com/episodes/2018/2/13/episode-26-cm-coolidges-dogs-playing-poker-1903

 

[pinball1970]

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?

 

[pinball1970]

Ya got to love the CIA. Please note the condescension of the last paragraph of this dossier.
https://pbs.twimg.com/media/EeVvhhyXYAMGThm?format=jpg&name=largeView attachment 290054

Motorcycle Diaries was a revelation to me (film) I had no idea regarding his background before that. I only knew about Che Guevara because of Monty python communist quiz and posters at university.
He looked cool.

 

[Keith_McClary]

TIL that Prof. Tom Murphy is posting again in his Do the Math blog and he has a free textbook :
Energy and Human Ambitions on a Finite Planet .

 

[kyphysics]

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.

 

[ergospherical]

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 :)

 

[Jarvis323]

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.

 

[jbriggs444]

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.

 

[dlgoff]

Today I Learned that @Greg Bernhardt wears a white hat.

 

[BWV]

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.

 

[Keith_McClary]

https://www.bloomberg.com/news/arti...lost-entire-savings-during-covid?srnd=premium

The bottom 20% has (had?) 2% of the wealth.
https://www.brookings.edu/blog/up-front/2019/06/25/six-facts-about-wealth-in-the-united-states/

 

[Frabjous]

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 6^th 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.

 

[phinds]

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.

 

[Jarvis323]

 

[Hornbein]

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.

 

[Hornbein]

Today I learned that illegal immigrants from the United States created the short-lived country of Texas.

 

[Borg]

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.

 

[Astronuc]

In sensitive fruit crops like apples and cherries, irrigation can heavily influence how trees grow and use nutrients—and ultimately determine fruit size and quality.
The optimal irrigation strategy for an apple or cherry orchard depends on a range of factors, from varietal and tree age to row spacing, soil type, topography, and climate. Aerial data can make it easier to determine the right approach by offering insights that account for the variability in these factors across your orchard.

https://www.ceresimaging.net/blog/u...imize-water-management-in-apples-and-cherries

The most rapid cell division in fruit occurs in the month or so after full bloom. Applying the right amount of water at this time is critical to achieving desired fruit size and quality at harvest. Too little water can reduce fruit set, limit fruit per cluster, and even lower yields in subsequent years.

In stone fruit, the final fruit swell phase—approximately two to three weeks before harvest—is also an especially important time to ensure that trees receive enough water for fruit growth. During this phase, it’s critical to avoid applying excess water: this can lead to fruit cracking or splitting, making them unmarketable.

 

[jack action]

TIL:

He was even inducted into the Rock and Roll Hall Of Fame in 1992.

 

[BWV]

Map of recipients of pensions for dependents of fallen Union soldiers outside the US in 1883

https://irishamericancivilwar.com/widows-dependents-in-the-atlantic-world/

https://irishamericancivilwar.com/wp-content/uploads/2019/10/Map.jpg

 

[Hornbein]

Guitarist "Skunk" Baxter is now a highly paid missle defense consultant.

 

[symbolipoint]

Post #2048,

I wonder how "self-taught" would be effective enough without more formally going through school (university) and going along with its necessary laboratory portion of course-work? Hard to accept that you gain much of that through learning on your own and access to electronic sound equipment and being able to look at the insides of algorithms.

 

[jack action]

TIL that if English and German have common roots, they shouldn't be considered to be "close" in every case:

 

[kyphysics]

Facebook has become Meta (for metaverse).

 

[rsk]

TIL that if English and German have common roots, they shouldn't be considered to be "close" in every case:

​

And then there's this - I know no german but the message is clear

 

[DrGreg]

Today I learned that, on IMDb, the user rating for the film This is Spinal Tap is displayed as marked out of 11 stars.

https://www.imdb.com/title/tt0088258/

Spoiler

The figure is actually calculated out of 10 (like any other film on IMDb) but incorrectly stated as being out of 11.

 

[kyphysics]

https://www.cnbc.com/2021/11/08/wal...s-to-ramp-up-its-online-grocery-business.html

Walmart is using fully driverless trucks to ramp up its online grocery business​

Walmart and Silicon Valley start-up Gatik said that, since August, they’ve operated two autonomous box trucks — without a safety driver — on a 7-mile loop daily for 12 hours. The Gatik trucks are loaded with online grocery orders from a Walmart fulfillment center called a “dark store.” The orders are then taken to a nearby Walmart Neighborhood Market grocery store in Bentonville, Arkansas, where Walmart is headquartered.

The program began in December 2020 after getting approval from the Arkansas State Highway Commission. The safety driver was pulled over the summer. The partnership is focused on the so-called middle mile — the transport of goods within the supply chain most often from a warehouse to a fulfillment center or a warehouse to a retailer.

 

[jack action]

TIL that Winston Churchill had his doctor prescribe him alcohol in order to avoid prohibition while visiting the US.

 

[BillTre]

TIL that Winston Churchill had his doctor prescribe him alcohol in order to avoid prohibition while visiting the US.

View attachment 292722​

NIce work-a-round if you can get it.

 

[jack action]

TIL that there is a Darth Vader grotesque on the Washington National Cathedral:

 

[jtbell]

Today I learned why cans of jellied cranberry sauce are inverted with respect to their labels.

When you store the cans with the label upright, the end with the crimped edge, which you open with a can-opener, is at the bottom. The rounded end, which is normally at the bottom, is at the top. An air space forms inside the can at that end, because the can isn't completely filled.

When opening the can, you have to flip it over briefly in order to use a can-opener. When you flip the can over again in order to empty it, the air at the rounded end causes the lump of jelly to slide out in one cylindrical piece, the way most people seem to expect.

The surprising reason why Ocean Spray cranberry sauce labels are upside-down (cnn.com)

It's also true for the Aldi store-brand cranberry sauce that we use.

(Happy Thanksgiving, by the way.)

 

[dlgoff]

Happy Thanksgiving, by the way.

And to you as well.

 

[berkeman]

When opening the can, you have to flip it over briefly in order to use a can-opener. When you flip the can over again in order to empty it, the air at the rounded end causes the lump of jelly to slide out in one cylindrical piece, the way most people seem to expect.

Very clever! That almost sounds like something that could have been patented...

 

[rsk]

This week I learned that the street where I live (don't judge, I've only been here a month) is named after a Vietnamese poet.

Ho Xuan Huong was a rebel of sorts, her poetry was scathing of societal norms and full of double entendres. She was known as "The queen of nom poetry" - nom being the writing system used in Vietnam before colonists adapted it to the latin alphabet.

I learned this because a newspaper article floated by on social media (don't judge, it's a great way of staying in touch with friends and family around the world) reporting that UNESCO is to honour her and a male poet, Nguyen Dinh Chieu, after whom the next street parallel to mine is named.

I haven't read any of his poetry yet but I will. In the meantime, here is one of hers, which I recognise because I remember seeing it on the wall of a cafe where they do the best veggie spring rolls in all of Hanoi.

Here is one of her poems

"Sisters, do you know how it is? On one hand,
the bawling baby; on the other, your husband
sliding onto your stomach,
his little son still howling at your side.
Yet, everything must be put in order,
Rushing around all helter-skelter.
Husband and child, what obligations!
Sisters, do you know how it is?“

Here is a page full of them

and here is the newspaper article

 

[BWV]

Ho Xuan Huong - Chinese name though, correct ?

 

[jtbell]

Map of recipients of pensions for dependents of fallen Union soldiers outside the US in 1883

https://irishamericancivilwar.com/widows-dependents-in-the-atlantic-world/

https://irishamericancivilwar.com/wp-content/uploads/2019/10/Map.jpg
View attachment 291248

The large clusters in Ireland and the German-speaking area surely reflect the waves of Irish and German immigrants beginning in the 1840s. I have great-great-grandfathers from Ireland and Switzerland, both of whom served in the Union Army in the Civil War. Fortunately both of them came home after the war.

According to family history/folklore, the Swiss one had to change his name when he enlisted in the Army, because it was too difficult for the recruiter. He took the name of the farmer whom he worked for as a laborer, a short non-German name that was easy to spell and pronounce. My father's mother and about half of his aunts and uncles ended up with that name.

 

[Keith_McClary]

1 Out of Every 15 Lights in The Sky Could Soon Be a Satellite, an Astronomer Warns ​

Starlink plans to replace each of the 42,000 satellites after five years of operation, which will require de-orbiting an average 25 satellites per day, about six tons of material. The mass of these satellites won't go away – it will be deposited in the upper atmosphere.

Because satellites comprise mostly aluminum alloys, they may form alumina particles as they vaporize in the upper atmosphere, potentially destroying ozone and causing global temperature changes.

This has not yet been studied in-depth because low Earth orbit is not currently subject to any environmental regulations.

That's only Starlink.
Scientists estimate that about 48.5 tons (44 tonnes or 44,000 kilograms) of meteoritic material falls on the Earth each day.

 

[nsaspook]

 

[BWV]

View attachment 293463This already happened back in February in Europe

 

[Keith_McClary]

View attachment 293463

If upside down means rotated by 180.

 

[DaveC426913]

If upside down means rotated by 180.

Technically, upside-down and right-to-left works.

 

[mfb]

1 Out of Every 15 Lights in The Sky Could Soon Be a Satellite, an Astronomer Warns ​

I glance up and notice a bright satellite moving across the sky, almost certainly a Starlink, since they now make up almost half of the nearly 4,000 operational satellites and they're extremely bright.

Almost certainly BS. The satellites are only bright shortly after launch when they fly in close formation. An individual bright satellite is not Starlink. But hey, reality wouldn't make such a good story!

With no regulation, I know that in the near future, one out of every 15 points you can see in the sky will actually be relentlessly crawling satellites, not stars.

This fails to mention the assumption of magnitude 6 visibility, which is extremely rare where most people live. If the limiting magnitude is 5 or even 4 - easily reached even in more rural places due to light pollution - the number of visible satellites is close to zero. And that's assuming no further improvement in making the satellites less visible.
It also fails to mention that this only applies to a relatively short window after sunset or before sunrise most of the time - which makes the assumption of magnitude 6 visibility questionable even without any light pollution.

It keeps going in that style. Misleading or just wrong claims all over the place. There are astronomers writing actually good articles with useful criticism, but this is not an example. It's just trying to mislead the public.