Today I Learned

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If only I could travel back in time and warn my 12 YO self, would have prevented many self-inflicted bruises

 
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Physics news on Phys.org
Screenshot 2022-12-07 at 7.52.59 AM.png
 
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TIL Adam and Eve owned the first computer. It was an Apple. It had one byte. We are still recovering from the first crash, hoping for a reboot, and remembering that on a clear disk you can seek forever.
 
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I recently found a podcast that I am thinking is pretty good.
It is Big Biology.
I would call it a serious biology podcast (as in science for adults).
 
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TIL that there is audio recording of the voice of Helmuth von Moltke the Elder, a man born in 1800 so technically in the 18th century. It was recorded on a wax cylinder in 1889, so the quality is extremely poor.
 
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BillTre said:
I recently found a podcast that I am thinking is pretty good.
It is Big Biology.
I would call it a serious biology podcast (as in science for adults).
Listened to the last episode during my commute this morning
https://www.bigbiology.org/episodes/2022/12/15/ep-94-synthesizing-life-on-the-planet-with-john-glass

these guys are trying to create the cellular equivalent of a model hydrogen atom - the simplest bacteria cell they can synthesize. They reduced this bacteria to 473 genes, and - surprising to me - biology still does not know what about 1/3 of the genes do.
 
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Today I learned I didn't know as much about angular momentum as I thought.

 
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Hornbein said:
oday I learned I didn't know as much about angular momentum as I thought.
Reminds me of a gyroscope. If it's spinning, it won't fall over.
 
TIL the effect of MRI machines on household items.

MRI
 
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Just found out a nice picture of a zebrafish a friend of mine (Dan Castranova) took is getting turned into a US postal stamp in a life magnified series:

Screenshot 2022-12-19 at 7.19.58 PM.png


the zebrafish is the forth down in the first column.
 
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TIL: Limpet teeth...

are grown as nanometer scale iron oxide (goethite crystals) and are the strongest (tensile strength) biologically produced material, stronger than spider silk. Apparently they may show up in your dentist's practice someday. Lots of interesting details here, if you need an excuse to waste some (more) time.
 
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We're expected to tip for take-out. . .when did this trend start in America?

In the "old days," take-out orders didn't have a tip expectation.
 
kyphysics said:
We're expected to tip for take-out. . .when did this trend start in America?

In the "old days," take-out orders didn't have a tip expectation.
"Expected?" Sez who?

I tip when someone brings the food to me.
 
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DaveC426913 said:
I tip when someone brings the food to me.
Same, but only if there is no 'service charge' on the bill.

... I hate 'service charge'. A tip is supposed to be about feedback too. Service charge feels like upvoting yourself. Simply - cheating. :oldcry:
 
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My fam went for a holiday dinner last week. Like, 13 of us. They put a service charge of 15%. (We call it an Autograt.)

I was on the edge of telling our servers I was planning to tip 20% as usual but that they'd taken that decision away from me...
 
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DaveC426913 said:
My fam went for a holiday dinner last week. Like, 13 of us. They put a service charge of 15%. (We call it an Autograt.)

I was on the edge of telling our servers I was planning to tip 20% as usual but that they'd taken that decision away from me...
The concept of waiters needing tips to actually have any sort of decent salary is something that never ceases to baffle me. I don’t stand outside the exam room with a cup for tips at the end of a course.
 
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Orodruin said:
I don’t stand outside the exam room with a cup for tips at the end of a course.
You should do. With a sign: "Give me a tip and I'll give you a tip."
 
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Orodruin said:
The concept of waiters needing tips to actually have any sort of decent salary is something that never ceases to baffle me. I don’t stand outside the exam room with a cup for tips at the end of a course.
My opinion is that it's just an excuse to not pay your employees as much, putting the fault on them if they don't make enough. "Oh, you should be better at your job if you want better pay!"
 
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Drakkith said:
My opinion is that it's just an excuse to not pay your employees as much, putting the fault on them if they don't make enough. "Oh, you should be better at your job if you want better pay!"
Also if you expect customers to tip 20% then your listed prices are ~17% lower than the customer actually pays. So it looks cheaper than it actually is.
 
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Today I learnt about tensors for the first time
 
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Orodruin said:
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Yeah, I've always known the symbols and terminology, but they sounded like witchcraft.
 
Ahmed1029 said:
Yeah, I've always known the symbols and terminology, but they sounded like witchcraft.
Yeah, found it truly disappointing that I could not use them to commune with the forces of evil.
 
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Canada’s Great Slave Lake was taken from the a translation of the Cree term for the lake, as that was Dene territory which they would raid and enslave captives. The Dene, not surprisingly, want the name changed.
 
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BWV said:
Yeah, found it truly disappointing that I could not use them to commune with the forces of evil.
You've obviously never said "Euler-Lagrange" three times in a mirror...
 
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