Today I Learned

  • Thread starter Thread starter Greg Bernhardt
  • Start date Start date
Join the discussion
Registration is free. Ask a follow-up in this thread, or start your own.
6,976 replies · 559K views
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.
 
Reply
  • Like
  • Haha
Likes   Reactions: Evo, hutchphd, jack action and 1 other person
Physics news on Phys.org
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.
 
Reply
  • Informative
  • Like
Likes   Reactions: Klystron and etotheipi
I am well informed by my engineering friends that the first 11 digits are precisely 3.0000000000
 
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.
 
Reply
  • Like
Likes   Reactions: etotheipi
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.
 
Reply
  • Haha
Likes   Reactions: Klystron and fresh_42
mfb said:
pi=10

Always choose the basis most convenient for the given task.
When you say "basis", do you mean "base", i.e.$$
1 \times \pi^1 + 0 \times \pi^0 \quad ?
$$
 
Reply
  • Like
Likes   Reactions: Klystron and fresh_42
Yes.
German uses "basis" both for vector spaces and bases of numbers, forgot that English does not.
 
Reply
  • Like
Likes   Reactions: DrGreg
@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
 
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.
 
Reply
  • Haha
  • Like
Likes   Reactions: waternohitter, BillTre, berkeman and 2 others
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)
 
Last edited:
Hemant said:
I was about run on street shouting "nasa found life on Mars"😑
Life found NASA on Mars!
 
Reply
  • Like
Likes   Reactions: BillTre
Pi, shmi. I like e the base of the natural logarithms. And its first digit is to too, two to, tutu, 2 also.
 
Reply
  • Like
Likes   Reactions: fresh_42
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."
 
Reply
  • Haha
Likes   Reactions: Klystron
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.
 
Reply
  • Informative
  • Like
Likes   Reactions: gmax137, strangerep and berkeman
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
 
Reply
  • Like
Likes   Reactions: Keith_McClary
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."
 
Reply
  • Like
  • Informative
Likes   Reactions: Keith_McClary, berkeman and fresh_42
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
 
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!
 
Reply
  • Haha
Likes   Reactions: Tom.G and Keith_McClary
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.”
 
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
 
Reply
  • Haha
  • Like
Likes   Reactions: pinball1970 and DaveC426913
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.