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.
  • #2,641
Bystander said:
Wood, or fiber glass?
At this point, fire.
 
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  • #2,642
Stephenk53 said:
TIL that Mars is about 3 light minutes away from us at its closest approach
Imagine playing Marco Polo with that much delay...
 
  • #2,643
Stavros Kiri said:
TIL what TIL means ...
Wise-as* answer: Test Intelligence Longingly
Real answer: Today I Learned (the title of this thread)
:eek: :sorry:
 
  • #2,644
Today, Stavros learned:

What TIL stands for.
:woot:
 
  • #2,645
DaveC426913 said:
Today, Stavros learned:

What TIL stands for.
:woot:
Til later ...
Til now I didn't know, ... s till learning! ... :smile:
 
  • #2,646
Drakkith said:
burn due to water-skis on fire.

Wouldn't stop drop and sink summarily extinguish the flames?

BoB
 
  • #2,647
rbelli1 said:
Wouldn't stop drop and sink summarily extinguish the flames?

BoB

Not if you're skiing on lava!
 
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  • #2,648
Stephenk53 said:
TIL that Mars is about 3 light minutes away from us at its closest approach
I'd like to think of it as 0 min in the photons frame ...
[So, we are in Mars! (!?) ...]:wink::cool:
 
  • #2,649
Today I learned the widely used "10 other cells per human cell in a human body" is probably wrong. A 2016 study revisited the estimates with improved methods and its result is 1:1.

(It was always clear that most of the mass of a human body is in human cells - that is easier to measure. The human cells tend to have much more mass per cell than foreign cells).
 
  • #2,650
So a Bacteria masses 1/350 what a Human cell does. That is quite a dynamic range. All that extra DNA maybe?
I wonder how a Virus compares, maybe a common cold virus.
 
  • #2,651
TIL a nice expression in integration: "If nothing works, use the substitution of desperation, the entire denominator."
 
  • #2,652
TIL that there is such a thing as "... standardised to the European Standard Population". Quite logical if you think about it, but I never had thought about it.
 
  • #2,653
TIL about personal responsibility. It's not fun cramming for school projects when the end of the semester is in a month and a half. Now I'm doing stress-relief math at 2 am.
 
  • #2,654
Today I learned that "Bohemian rhapsody" is the most performed song of the 20th century. Perhaps I should change the title of my recent paper linked in my signature and call it "Bohmian rhapsody for instrumentalists".
 
  • #2,655
CaptainAmerica17 said:
TIL about personal responsibility. It's not fun cramming for school projects when the end of the semester is in a month and a half. Now I'm doing stress-relief math at 2 am.
You're the captain! ...
 
  • #2,656
Stavros Kiri said:
You're the captain! ...

With great power comes great responsibility!
 
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  • #2,657
TIL about the following site:
This link will display the photo for the current day. With your cursor on the picture, the symbol ">" on the right shows you the previous day's photo. If you keep clicking on this symbol, you will see the series of photos day by day going back at least to December 2017. I do not know how far back the series goes.

Hope you find this entertaining, but beware, it can become addictive.
 
  • #2,658
Demystifier said:
"Bohemian rhapsody"

not the "Queen" version surely..

i'd assumed it was a sibling to this one
 
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  • #2,659
CaptainAmerica17 said:
With great power comes great responsibility!
Keep it up! ...
 
  • #2,660
Today I learned about the airport cell phone lot.

For the first time in several years, I had to pick up a guest at the nearest airport. I figured I would do what I had done before, namely park in the garage, go into the terminal to meet him at the baggage claim, then pay a couple of dollars when leaving the garage.

Along the entrance road, I saw a sign, "Cell Phone Lot." Aha! I could park there for free, wait for my guest to text me his location at the curb in front of the terminal after he arrived and picked up his bags, and then simply zip over to the terminal. This is not a huge airport like Chicago O'Hare, so just 2-3 minutes after his text, we were on our way.

As I was leaving the cell phone lot, I noticed that most of the other cars were parked facing the opposite direction to me. Behind me (and in front of them) was an electronic flight arrival board similar to the ones inside the terminal. I hadn't noticed it when entering the lot, and I was checking the arrival status on the airport's website on my phone anyway, so I didn't really need it. It reminded me of a drive-in movie theater. :cool:

Just now I've read online that some cell phone lots also have restrooms, and even food trucks to provide refreshments.
 
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  • #2,661
I am confused.
1] What does a cell phone have to do with the lot? I'm guessing you can wait there and have the arriver call when he's coming out?
2] What about 'cell phone lot' made you realize it would be free?
 
  • #2,662
DaveC426913 said:
I am confused.
1] What does a cell phone have to do with the lot? I'm guessing you can wait there and have the arriver call when he's coming out?
Exactly. And I could amuse myself by reading PF etc. on my phone while waiting.
2] What about 'cell phone lot' made you realize it would be free?
I had to drive into the entrance to investigate. It was actually "carved out" from part of a paid parking lot, using a fence. The paid part required driving through a gate; the cell phone part didn't. A sign stated that one could park in the cell phone lot for up to 30 minutes, and the vehicle must be attended at all times.

Now that I think of it, the "paid" part of the lot must be for airport workers, with the gate triggered by an ID card. It's not far from the cargo area, but kind of a long hike from the passenger terminal.
 
  • #2,663
jtbell said:
Along the entrance road, I saw a sign, "Cell Phone Lot." Aha! I could park there for free, wait for my guest to text me his location at the curb in front of the terminal after he arrived and picked up his bags, and then simply zip over to the terminal. This is not a huge airport like Chicago O'Hare, so just 2-3 minutes after his text, we were on our way.
Who knows, may be in the future (e.g. with 5G net, coordinated autonomous vehicles and planes, intenet of things etc.) we could even have more drive-through and drive-in services and facilities at airports, such as e.g. drive though check in (and baggage check in), drive through baggage claim, drive in waiting lot and check in and ticket issue automatically via the inernet, from your car, with smartphone or computer and portable printers ...
That would save time waiting in lines, or cut down on the suggested "2 hours in advance" ...
We could even see drive-through boarding on planes (in connection to the former drive through check in and baggage ...).
All that, of course, before we are all able to have our own "flying vehicles" ...
 
  • #2,664
Stavros Kiri said:
Who knows, may be in the future (e.g. with 5G net, coordinated autonomous vehicles and planes, intenet of things etc.) we could even have more drive-through and drive-in services and facilities at airports, such as e.g. drive though check in (and baggage check in), drive through baggage claim, drive in waiting lot and check in and ticket issue automatically via the inernet, from your car, with smartphone or computer and portable printers ...
That would save time waiting in lines, or cut down on the suggested "2 hours in advance" ...
We could even see drive-through boarding on planes (in connection to the former drive through check in and baggage ...).
All that, of course, before we are all able to have our own "flying vehicles" ...
I see some problems there. A lot of the red tape in airports is redundancy is passive security - such as physically clapping eyes on who is picking up the tickets, and who is dropping off luggage. Every monitored checkpoint is another place where ne'er-do-wells can get caught.

While it would be freakin' awesome to drop my luggage straight from my trunk to the conveyor, I'm not sure it's worth the security risk.
 
  • #2,665
DaveC426913 said:
I see some problems there. A lot of the red tape in airports is redundancy is passive security - such as physically clapping eyes on who is picking up the tickets, and who is dropping off luggage. Every monitored checkpoint is another place where ne'er-do-wells can get caught.

While it would be freakin' awesome to drop my luggage straight from my trunk to the conveyor, I'm not sure it's worth the security risk.
Security is one problem. I am sure there are others too. I was planning to mention it but at the end I forgot. However, the same issue is central with a 5G net and internet of things, which they are currently working to improve (security). The red tape for security could (potentially) get alleviated, and more advanced sensors etc. would be designed for the drive-through purposes, I guess.
 
  • #2,666
DaveC426913 said:
While it would be freakin' awesome to drop my luggage straight from my trunk to the conveyor, I'm not sure it's worth the security risk.
Imagine that I had been of the firm opinion - before 9/11! - that flying takes too long, especially on shuttle routes like London - *. I seriously thought that it should become like a bus trip sooner or later. Why should it take hours to check in on a flight that lasts no longer than 3 hours? On highly frequently routes I thought: "arrival at the airport - buy the ticket - check in - board" should be a matter of ten minutes! E.g. if you have a look on the passengers on a Monday morning between London and Frankfurt, then you will see: they do not fly, they commute!
 
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  • #2,667
I visited a recently remodeled store implementing customer service queues such as at a bank. Several 'tellers' in windows with waiting lines. Customers gather in an outer waiting room. Periodically, all available customers are ushered en masse to fill the queues for next_available_teller.

All well and good except each window has its own queue! (I refrained from calling "Form one line!").

Mass of customers fill open queues and wait for 'their' teller. No crossing to other lines. Has management defeated the purpose of a queue?

[Now I'm curious given N open windows how many wait queues are optimum? Also given maximum occupants in the room? Applying mental min-max tells me one per room; but I hate waiting in lines :cool:]
 
Last edited:
  • #2,668
Today I learned that the first detected black hole merger released more than 3 solar masses of energy as gravitational waves in less than a second. This was equivalent to 5.3x1047 joules, and the peak power was greater than the power output of all stars in the visible universe combined. COMBINED.
 
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  • #2,669
fresh_42 said:
On highly frequently routes I thought: "arrival at the airport - buy the ticket - check in - board" should be a matter of ten minutes!
Boarding alone takes longer than that unless it is a really small plane.
You can arrive at the airport an hour before your flight - if you don't have checked bags and get priority access at the security checkpoint (easy to get if you fly frequently) that is enough time. Boarding for big airplanes begins something like half an hour before the flight.
 
  • #2,670
It took too long, it takes too long, and no betterment in sight! My dream of the layout of the boards everywhere is:
"destination - Airline - available seats - departure (- maybe costs)"
and a realistic expectation of time required: Check opportunities, go to the check in and buy the ticket (10m), go to the gate (5m, even on large air ports), boarding (5m - since there is no need to board all at once!), reserve time (10m) = 30m in total.

I know it is impossible for several reasons, but that was what I dreamt of: it should be as easy as a trip by bus or taxi. I remember once on SVO: I had to x-ray the same backpack at least four times all in all (don't remember the exact number, but it was ridiculous). Of course it was not ridiculous if you take these idiots into account, but that was part of my vision, too, that people do not murder strangers and everybody just wants to get from A to B.
 

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