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.
  • #4,681
Tom.G said:
Rather well in fact.
Actually, I knew that mercury bearings existed because Michelson and Morley had their interferometer on one in their experiment that discovered the isotropy of light speed. A bit like the battleship in a bucket of water, I hadn't thought of it as "floating". Although I should have.
 
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  • #4,683
jack action said:
TIL the worst year ever was 536:


Yeah that was definitely worse than dates I had in my head.
 
  • #4,684
TIL (TWIL) I was wrong about something regarding the human eye, colour, physics, pigments, the iris.
Eye colour is more physics than Chemistry. At least for certain colours. Jim smelt a rat immediately. Obviously!
 
  • #4,685
TIL skydiving is not scary.
 
  • #4,686
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  • #4,687
TIL that some folks like to bring generators and extra power sources when they go camping, apparently to power their fans so they can stay cool while using their laptops. From my Facebook feed today...

1665686370368.png
 
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  • #4,688
That's called 'glamping' - a portmanteau of glamor and camping.

Or 'boujee', depending on your attitude toward it.
 
  • #4,689
DaveC426913 said:
That's called 'glamping' - a portmanteau of glamor and camping.

Or 'boujee', depending on your attitude toward it.
I thought glamping was where the tent is more like little house? A shed with facilities?
I never saw the point, if people are not keen on the tent element of the out doors but like the country side, just get a nice B&B instead.
 
  • #4,690
pinball1970 said:
I thought glamping was where the tent is more like little house? A shed with facilities?
I never saw the point, if people are not keen on the tent element of the out doors but like the country side, just get a nice B&B instead.
The purpose for the tent is portability, even if setup and repack is a chore.
 
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  • #4,691
symbolipoint said:
The purpose for the tent is portability, even if setup and repack is a chore.
Yes that's why I don't get glamping, it neither one thing not the other. Some of the pods you can buy are in the region of 4000 $ plus!
May as well just get a caravan, you can least go to different locations.

Camping for me is supposed to be a bit make do, a bit cold at night, a bit stiff from the floor and see how inventive you can get with little camping stove.
Or at least it was till I got too old for it.
Hotel with room service and power shower these days.
 
  • #4,692
pinball1970 said:
I never saw the point
I would generally agree, but there's a place in the South Downs somewhere with an old Westland Wessex (British variant of the H34 Choctaw, for Americans) you can stay in, which is off-beat enough that I'm tempted...
 
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  • #4,693
pinball1970 said:
Camping for me is supposed to be a bit make do, a bit cold at night, a bit stiff from the floor and see how inventive you can get with little camping stove.
Make camp when tired and be on foot in an hour after waking up naturally who-knows-where...

Sigh... I'm also already too old for that. But still missing.
 
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  • #4,694
Rive said:
Make camp when tired and be on foot in an hour after waking up naturally who-knows-where...

Sigh... I'm also already too old for that. But still missing.
I immediately thought of all the great trips with my uni mates. Lake District, Peak district, Glastonbury (once) Donington rock, Knebworth.
One time, Clacton-on-sea!

No matter where we ended up or what condition we were in by the time we went to sleep, my mate would always go bird watching in the morning. He is still an avid twitcher.
 
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  • #4,695
TIL Robbie Coltrane has died. He was 72. Dr Johnson in Black Adder was my introduction, then Cracker.
Potter after that. Very sad. Some great characters we can remember. RIP
 
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  • #4,696
Angela Lansbury died last week too. She was 96 had a great innings. Most people associate her with "Murder she wrote."
A little bit last of the summer wine, for old people if you are UK.
She was a big movie star (yanks will know this) She was part of one of my favourite films.
Samson and Delilah. Visually very beautiful but horrific in places ( I think I watched with gran who was liberal!)
Anyway, it's always sad to see someone part of your childhood pass. RIP
 
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  • #4,697
pinball1970 said:
Anyway, it's always sad to see someone part of your childhood pass. RIP
This made me think of The 3 Stooges, who were a child favorite of mine. As a young boy I had no idea that Curly was already dead a decade before I was even born, and Shemp not much later. :oldcry:

Also, TIL that Shemp was Moe's brother.
 
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  • #4,698
pinball1970 said:
Angela Lansbury died last week too. She was 96 had a great innings. Most people associate her with "Murder she wrote."
A little bit last of the summer wine, for old people if you are UK.
She was a big movie star (yanks will know this) She was part of one of my favourite films.
Samson and Delilah. Visually very beautiful but horrific in places ( I think I watched with gran who was liberal!)
Anyway, it's always sad to see someone part of your childhood pass. RIP
Learned that she moved her family to Ireland from LA in 1969 to separate her teenage daughter from some hippie cult leader she had fallen in with

whose name was Charles Manson
 
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  • #4,700
strangerep said:
This made me think of The 3 Stooges, who were a child favorite of mine. As a young boy I had no idea that Curly was already dead a decade before I was even born, and Shemp not much later. :oldcry:

Also, TIL that Shemp was Moe's brother.
Curly (Jerome) was also a Howard (Horowitz) brother. Curly actually replaced Shemp early (pre-Columbia Pictures deal) in their history. Larry Fine (Feinberg) was someone they met doing vaudeville and became fast friends and collaborators, eventually Joining Ted Healy and his Stooges.

They actually have a really interesting history. Moe wrote an unfinished autobiography what was very heavy on their early years but pretty scant on their later history... it was edited and cleaned up for publication after his death.
 
  • #4,701
strangerep said:
I had no idea that Curly was already dead a decade before I was even born
Curly's Pants by Corky and the Juice Pigs

They were the pants that Curly died in
They were the pants he could not hide in
And they had a button fly
And they poked me in the eye (Whadja do that for?)
And it was my defeat
When I wore them on the street
'Cause I would go
(Whoop Whoop whoop whoop!)

 
  • #4,702
TIL that MotoGP riders have airbags in their leathers that activate during crashes to add protective padding to their upper body parts. I only found out about it because apparently one of the riders in last weekend's Australian Gran Prix race had his airbags go off accidentally due to some violent shaking of the bike coming out of a turn. He said it was awkward trying to ride while feeling like the Michelin Man, all extra puffy. It took about a lap for the air bags to fully deflate for him.

1666030529400.png


https://www.autosport.com/motogp/news/safety-devices-in-motogp-airbags-helmets-boots/6438518/
Airbag

The most complex of these is the airbag, which has been used in MotoGP for years but finally became mandatory in 2018. It is positioned around the back, shoulders and rib cage inside the suit, and is designed to absorb the forces endured by riders when they fall off their bikes.

Race suits are fitted with accelerometers, gyroscopes and a GPS, and the airbag is activated when sensors detect that a fall has occurred. The software is very clever and can tell the difference between a genuine incident and a near miss, so inflation doesn’t occur at random.

Two gas canisters are secreted inside the suit, and when the system detects a fall the chambers of the airbag fully inflate in just 25 milliseconds; about a quarter of the time it takes to blink. They stay inflated for around five seconds, by which time a rider will usually have come to a stop.
 
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  • #4,703
Still pretty confused by the whole Bell thing.

In order to get a grasp on what Clauser and the others did you have to understand Bell and to understand Bell you have to understand EPR and a few bit and pieces inbeween.

(thanks guys for the links papers and videos- I am still working through them)
One thing I absolutely do not understand is the political part to it.

When Bell came up with a way to test the EPR why did he not shout it from the roof tops in 1964?

It was an answer to the Einstein Bohr debate how could it not be important? He worked at CERN and did not tell his colleagues about the paper

When Clauser started researching to test Bell in the late 60s early 70s why was he discouraged? He was told it would ruin his career.

One quote was from Feynman, “Quantum physics is right!” Why are you even looking??

They did not actually know about hidden variables though did they?

How could this be a non-issue?
 
  • #4,704
pinball1970 said:
When Bell came up with a way to test the EPR why did he not shout it from the roof tops in 1964?

It was an answer to the Einstein Bohr debate how could it not be important? He worked at CERN and did not tell his colleagues about the paper

When Clauser started researching to test Bell in the late 60s early 70s why was he discouraged? He was told it would ruin his career.
Generations of physicists have struggled to understand quantum theory. (And they still do!) There was a general atmosphere of frustration, and most physicists succumbed to Bohr's (almost transcendental) philosophy, that the human mind is tied to classical concepts, and that quantum theory can only be formulated in terms of complementary concepts of classical mechanics. And, yes, studying the foundations of quantum mechanics was a career hazard! (I'm probably not the only one who can confirm that!)
pinball1970 said:
One quote was from Feynman, “Quantum physics is right!” Why are you even looking??
Feynman had also this to say (The Character of Physical Law):
I am going to tell you what nature behaves like. If you will simply admit that maybe she does behave like this, you will find her a delightful, entrancing thing. Do not keep saying to yourself, if you can possibly avoid it, 'But how can it be like that?', because you will get 'down the drain', into a blind alley from which nobody has yet escaped. Nobody knows how it can be like that.
pinball1970 said:
How could this be a non-issue?
The situation has changed dramatically through the work of the brave experimentalists, who have created a new industry with quantum cryptography, quantum teleportation, and quantum computation. But we still don't really understand quantum theory. (Hopefully before the hundredth anniversary 2025.)
 
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  • #4,705
 
  • #4,706
BillTre said:
Researchers have created a device that uses machine vision to spot cockroaches and zap them with a laser.
What could possibly go wrong? :wink:
 
  • #4,707
berkeman said:
What could possibly go wrong? :wink:
I have no idea.

cockroach_costume.jpg
 
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  • #4,708
berkeman said:
What could possibly go wrong? :wink:
Cockroach insurgency stealing the tech, leading to cockroaches armed with AI driven auto-targeting anti-human lasers?
 
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  • #4,709
BillTre said:

I have once seen ants doing that job. Very impressive.
 

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