Today I Learned

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Today I learned that cleaning a white hat can be done with bleach cleaner, but it’s important to rinse it before wearing it again. I also discovered that "oyster veneering," a woodworking technique from the late 1600s, is experiencing a minor revival despite its labor-intensive nature. Additionally, I learned that the factorial of 23 (23!) equals 25,852,016,738,884,976,640,000, which interestingly has 23 digits, a unique coincidence among factorials. I found out that medical specialists often spend less than 10 minutes with patients, and that watching TV can contribute to weight gain. Other insights included the fact that a kiss can transfer around 80 million microbes, and that bureaucracy can sometimes hinder employment opportunities. The discussion also touched on various trivia, such as the emotional sensitivity of barn owls and the complexities of gravitational lensing around black holes.
  • #3,631
etotheipi said:
I memorised all 11 digits of pi this morning
I know all the digits of pi[1]. It's just the order I have trouble with.

[1] There are only two if you work in binary.
 
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  • #3,632
Ibix said:
I know all the digits of pi[1]. It's just the order I have trouble with.

[1] There are only two if you work in binary.
No need to memorize the order, I have heard they are random.
 
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  • #3,633
I am well informed by my engineering friends that the first 11 digits are precisely 3.0000000000
 
  • #3,634
etotheipi said:
I am well informed by my engineering friends that the first 11 digits are precisely 3.0000000000
Only during the undergraduate study. It turns out to be 22/7 in the master classes.
 
  • #3,635
fresh_42 said:
Only during the undergraduate study. It turns out to be 22/7 in the master classes.

Nonsense, 22/7 has an infinite decimal expansion, whilst by the fundamental theorem of engineering it's trivial to see that ##\pi## must in fact terminate.
 
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  • #3,636
pi=10

Always choose the basis base most convenient for the given task.
 
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  • #3,637
mfb said:
pi=10

Always choose the basis most convenient for the given task.
When you say "basis", do you mean "base", i.e.$$
1 \times \pi^1 + 0 \times \pi^0 \quad ?
$$
 
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  • #3,638
Yes.
German uses "basis" both for vector spaces and bases of numbers, forgot that English does not.
 
  • #3,640
@hutchphd Indiana is # 12 in a list of states for deaths per 100M from Covid. Not enviable.
From here:
https://www.worldometers.info/coronavirus/country/us/

Screenshot_2021-03-31 United States Coronavirus 31,166,344 Cases and 565,256 Deaths - Worldome...png
 
  • #3,641
We have both lots of old people and lots of the "less important" people. Actually the vaccination program here has been surprisingly good (I got my second Moderna two weeks ago at the Kroger three blocks from my door...I am 69) so I am not personally very worried. Good thing I am computer literate (and white) of course.
 
  • #3,642
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  • #3,643
Jarvis323 said:
Whoaa! Life on Mars! They've found it!

NASA Announces Life on Mars
I was about run on street shouting "nasa found life on Mars"😑
 
  • #3,644
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  • #3,646
fresh_42 said:
Only during the undergraduate study. It turns out to be 22/7 in the master classes.
I like to think of myself as a 355/113 guy.

(355/113 - Pi ~ 2.7e-7)
 
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  • #3,647
Hemant said:
I was about run on street shouting "nasa found life on Mars"😑
Life found NASA on Mars!
 
  • #3,648
Pi, shmi. I like e the base of the natural logarithms. And its first digit is to too, two to, tutu, 2 also.
 
  • #3,649
Klystron said:
Pi, shmi. I like e the base of the natural logarithms. And its first digit is to too, two to, tutu, 2 also.
Here, let me help: "And its first digit is Desmond."
 
  • #3,650
Klystron said:
Pi, shmi. I like e the base of the natural logarithms. And its first digit is to too, two to, tutu, 2 also.
gmax137 said:
Here, let me help: "And its first digit is Desmond."
Think... think... Desdemona?... Desiderius?... "click!"... "Desmond Tutu!" lol.
 
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  • #3,652
TIL about Roman dodecahedrons. They have been found in many places, so they were clearly a thing - but no one knows why.
 
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  • #3,653
mfb said:
TIL about Roman dodecahedrons. They have been found in many places, so they were clearly a thing - but no one knows why.
That is completely clear to me. It is a "Knochen". Sorry, I have no idea how to find the English word for it.

330px-Knochen_%28Werkzeug%29.jpg
 
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  • #3,654
fresh_42 said:
That is completely clear to me. It is a "Knochen". Sorry, I have no idea how to find the English word for it.

View attachment 281411
In the U.S. it is a "Dog Bone Wrench."
 
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  • #3,655
fresh_42 said:
That is completely clear to me. It is a "Knochen". Sorry, I have no idea how to find the English word for it.
With round holes with inconsistent diameter?

Knochen=Bone
 
  • #3,656
mfb said:
With round holes with inconsistent diameter?

Knochen=Bone
The Romans were around in many places. They've found the artifact only in Celtic areas. Ergo: universal beer bottle opener!
 
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  • #3,657
mfb said:
TIL about Roman dodecahedrons. They have been found in many places, so they were clearly a thing - but no one knows why.
I always like when we find mysterious ancient tech. It keeps us humble.

I also like the line from the wiki
”A Roman icosahedron has also come to light after having long been misclassified as a dodecahedron.”
 
  • #3,658
mfb said:
TIL about Roman dodecahedrons. They have been found in many places, so they were clearly a thing - but no one knows why.
I knew what to do with those when I was 2 years old:

il_fullxfull.1372136211_q8eu.jpg
 
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  • #3,659
fresh_42 said:
They've found the artifact only in Celtic areas. Ergo: universal beer bottle opener!
Hmm. So much for my spagghetometer theory.

image.jpg
 
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  • #3,660
fresh_42 said:
They've found the artifact only in Celtic areas. Ergo: universal beer bottle opener!
Snake trap, invented by an ex-Roman slave.
 

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