Today I Learned

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In summary: Today I learned that Lagrange was Italian and that he lamented the execution of Lavoisier in France during the French Revolution with the quote:"It took them only an instant to cut off this head and a hundred years might not suffice to reproduce it's...brains."
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nitsuj said:
that's because it's not true lol
lol :D
 
Physics news on Phys.org
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Craftek_Ana said:
lol :D
yes; classic case of fake news :smile:
 
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newjerseyrunner said:
Today I learned that NEWS is an acronym for Notable Events, Weather, and Sports.
Whereas MATHS stands for Mathematical Anti-Telharsic Harfatum Septomin

Ref: https://en.wikiquote.org/wiki/Look_Around_You#Maths
 
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PHYSICS - Potentially HYgroscopic Science Institutes Collecting Saltwater Sweat
 
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Today I learned that cave systems often have caverns and tunnels named such names as, "The Big Chamber Near the Entrance", "The Big Chamber Nowhere Near the Entrance", and "The Birth Canal".
 
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TIL that I should have trained in wrestling instead of Karate. No offense to my old sensei but I never got to fly through the air and land in pieces of foam like these guys. This is so awesome.

 
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Aufbauwerk 2045 said:
TIL that I should have trained in wrestling instead of Karate. No offense to my old sensei but I never got to fly through the air and land in pieces of foam like these guys. This is so awesome.



If you wanted to do that, you should have done gymnastics like I did. :biggrin:
 
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TIL that I can learn something even from nausea-inducing television. I was watching a program featuring a guy from some EMP "task force." I became curious about the major event c. 1858 that, according to the guest, fried the telegraph system. By following links, I came across the name Loomis, an American mathematician who was interested in astronomy and meteorology. He reported on the phenomenon at that time. Then I looked him up on archive.org and discovered he wrote some mathematics textbooks, which are free to download. So now, after being awakened from my sound sleep by someone playing hip-hop music from their automobile, loud enough to wake the whole neighborhood, I downloaded the Loomis textbooks. Now I'm reviewing cycloids. I honestly was not aware of just how fascinating they are. It seems the Loomis books influenced Chinese mathematics education. I have not learned exactly who is influencing American mathematics education today.
 
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  • #2,462
I seem to be learning a lot this week, or maybe it's because I was taking it easy for a few days, after working myself to physical and mental exhaustion. That's why I was posting so much, after being away for several months. I'm getting back to work now, but first a word about Memorial Day.

TIL that while I have a lot of respect for my ancestors who fought in so many wars, on this Memorial Day my main thanks to them is for surviving. It's good to be alive. Thank you all. I try to do something worthwhile in my life, to make up for all your hard work and sacrifice over the years.

I'm thinking of several Civil War ancestors in particular. Did you ever see the movie "Gettysburg?" I had two ancestors who fought there. One was in a regiment that had 41% casualties. They were the lucky regiment. The other regiment had 72% casualties. I realize how fortunate they were and how fortunate I am to be alive. Which side were they on? Honestly, that no longer concerns me. The main thing to me is that they survived.

I also had WWI and WWII ancestors. Perhaps their odds of survival were higher than in previous generations, perhaps not. The important thing to me is that they survived.

The best part of war is when the soldiers come home to their families. I can't watch war movies any more. Instead, if I think about it, I go on Youtube and watch videos of returning soldiers surprising their kids at school.

Anyway, thanks again my soldier ancestors. That of course includes Army, Navy, Air Force, and Merchant Marine. I don't know of any ancestors who were Marines, but it would not surprise me if there were some. One of my uncles was 82nd Airborne.

I hope our politicians make good on their promises about taking care of veterans. Talk is cheap.
 
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Today I learned about this song. It's a good follow-up to Memorial Day, and in line with my musical reply to some bluegrass in another thread. It's about a Civil War soldier from Gettysburg who was found with a picture of his three children.

www.youtube.com/watch?v=iXJGC0nflQM&index=7
 
  • #2,464
Today I learned that it is the light particle that is behind everything and influences all the behaviors of all other particles. And because of that it appears as if there is something like gravity out there, but in truth there is no such thing as gravity, it just looks like there is. It is just the collective behavior of particles with the light particle setting the stage for all actions of all objects. Interesting, eh?
 
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DannyHeim said:
Today I learned that it is the light particle that is behind everything and influences all the behaviors of all other particles. And because of that it appears as if there is something like gravity out there, but in truth there is no such thing as gravity, it just looks like there is. It is just the collective behavior of particles with the light particle setting the stage for all actions of all objects. Interesting, eh?
That is most likely wrong.
 
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you can also find physicists who think it's all waves.
 
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Today I learned yet again that I'm more likely to discover solutions to tricky problems by thinking about them in peace, away from computers, books, pencil and paper. As my job involves computers, books, pencil and paper, I often forget that! In my first computer job, 45 years ago, I frequently managed to solve problems in my head during the bus journey home which I had failed to solve in hours of debugging, and that pattern has continued ever since. OK, it's necessary to get enough information first, but going away and just thinking about it is important.

The only snag with that approach is that sometimes I have forgotten the solution (or even that I found a solution) by the time I get an opportunity to write it down!
 
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  • #2,468
I've read somewhere that Hamilton found his skew field on a walk through a park, pausing on a small bridge, after years of searching an extension of dimension three over the reals.
 
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  • #2,469
I learned of Consumer Reports - a non-profit, non outside ad-accepting reviewer of consumer products. They don't even allow their positive reviews to be used as selling points of product manufacturers. So, they are ruthlessly objective. I love it!

They are awesome. None of the crap with people literally buying fake positive reviews or incentivizing a rating on product reviews. They have a subscriber base of over 7 million and an annual product testing budget of about $25 million on average.

My mom laughed at me and said she used to buy their print magazines decades ago and I'm kind of slow. Guilty as charged.

Having said that, I wish there was a consumer reports of local business services. I only see stuff like Google Reviews and Yelp, which have so much fake stuff that it's hard to trust anyone.
 
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  • #2,470
Jonathan Scott said:
The only snag with that approach is that sometimes I have forgotten the solution (or even that I found a solution) by the time I get an opportunity to write it down!

I can relate to that. I heard of a noted inventor (I think) who often had great ideas while laying in bed. He kept a note pad at bedside to write down the ideas before he forgot them.
 
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kyphysics said:
I wish there was a consumer reports of local business services.
Try the site of the Better Business Bureau in the city that the company or store is in.

A Google search of 'BBB' followed by the city usually finds it.
 
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Tom.G said:
Try the site of the Better Business Bureau in the city that the company or store is in.

A Google search of 'BBB' followed by the city usually finds it.

That's a good one. I forgot about that.

I've checked their page a few times, but don't always find it super useful. But they are still better than other sources, due to how they handle complaints and discuss them publicly.

I'd rate Google Reviews dead last, as you can buy reviews or easily create a fake account and just review something you have never used. Worse is the ability to

Yelp is slightly better, because people post pictures of problems and positives (e.g., a roach in the food or a perfectly prepared meal at an expensive restaurant). Having some proof really helps, but you can still run into the problem of fake accounts/reviews there too (where they just don't post pics/receipts for proof of visit).

I like Consumer Reports and BBB's independence on matters that prevents bribery.
 
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re: BBB's independence & bribery

That may or may not be true. From Wikipedia:

The Better Business Bureau is not affiliated with any governmental agency. Businesses that affiliate with the BBB and adhere to its standards do so through industry self-regulation. To avoid bias, the BBB's policy is to refrain from recommending or endorsing any specific business, product or service.[6]

The organization has been the subject of controversy, particularly related to its alleged practice of giving higher ratings to businesses that pay a membership fee. The BBB disputes the claim that payment from businesses is required for them to receive an "A" rating.[7]Business consultant and previous national Manager of Customer Service for Checker Auto Parts Eva Love observed, "Complaining about a business to the Better Business Bureau is like complaining to the mouse's mother after a mouse steals your cheese. It will help if the wind is blowing in your direction."[8]

also

It has been reported that the BBB encourages and solicits money from the very businesses they monitor which, again, raises the question of neutrality.[29] The BBB states that they hold their Accredited businesses to a higher standard, as outlined in their Accreditation standards.[30] This behavior is likely the reason for such backronyms as, "Better for Businesses Bureau" and "Bribes from Businesses Bureau," popular nicknames for the organization presumably stemming from the frustration regarding the above criticisms.

On December 22, 2010, William Mitchell, CEO of the Los Angeles BBB, and originator of the BBB letter grading system, resigned as a result of an internal investigation conducted by the CBBB.[7][31] The resignation was rescinded shortly afterward, however, with Mitchell claiming that his health prompted him to resign, and criticizing the National Council for attempting to take over the Southern California chapter.[32]
 
  • #2,474
Today I learned that bees (vegetarians) evolved from wasps (carnivores).
 
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Today I learned about a manuscript of Euclid's Elements that has been scanned and is now available online. To quote from the webpage:

"The manuscript MS D'Orville 301 contains the thirteen books of Euclid's Elements, copied by Stephen the Clerk for Arethas of Patras in Constantinople in 888 AD. It is kept in the Bodleian Library at the University of Oxford."

This reminds me of something else I learned recently. In school I was taught that the Renaissance happened in part because of (1) the invention of the mechanical printing press with movable type by Gutenberg and (2) the growing independence of wealthy Italian city-states, where patrons could support humanist scholars without interference from the Pope and (3) the Protestant reformation which led to a surge in literacy in Europe. I was also taught that (4) Crusaders brought back Arab manuscripts which were translations of ancient Greek works, and this helped Europe rediscover its lost Greek heritage.

But notice that this manuscript was produced in Constantinople, the center of the Eastern Roman Empire, in 888 A.D.. This was before the Great Schism which separated Latin from Orthodox Christianity, before the Crusades, and also of course long before Constantinople fell to invaders.

What I learned recently is that in fact the fall of Constantinople in 1453 was one of the major causes of the Renaissance. This is because refugee Greek-speaking scholars fled to the western part of the empire with good manuscripts, where they collaborated with Latin scholars to produce Latin translations of the Greek originals. https://www.claymath.org/euclids-elements
 
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fresh_42 said:
As far as I've experienced, they are home in basically every culture. The meat might differ, and often they are wrapped in pasta dough and cooked, and they have different names, but in the end they all are the same.

There is a certain region here, where meat in pasta have a very funny (unofficial) name: Herrgottsbescheißerle. It's difficult to translate, but it means "screws the Lord". They are basically pelmeni, just German instead of Russian. The name came from the Middle Ages and they were eaten during lent, although forbidden. But as they were hidden behind the dough, the Lord couldn't see it.

Even grilled meatballs have a couple of different names in Germany alone, depending on the region. I think it's a bit like apple-pie: everybody has it.

Speaking of pasta, I learned on the 4th of July that the song "Yankee Doodle" owes something to pasta. I always wondered why Yankee Doodle stuck a feather in his cap and called it macaroni. Here's the story.

A Yankee is of course named after the Dutch "Jahnke." Apparently the Dutch used it to refer to the English newcomers who were encroaching on New Amsterdam in the early 1600s.

A "doodle" is another word for a "dandy," in other words a pretentious fellow who wants to show off his sophistication by dressing in what he thinks is an upper-class style. The word "doodle" eventually was shortened to "dude."

Many young Englishmen who could afford it did the Grand Tour. They traveled from England to some of the great cities of the Continent, including Rome. In Italy they came across pasta, which was not known in England. They fell in love with pasta and brought the taste for it back to England. Advertising one's enjoyment of pasta was seen as another pretentious act by the dudes of that time.

In other words, what the Brits were saying in the song is that the American colonists were a bunch of pretentious upstarts. Which I suppose we were, from the British perspective.

:)

p.s. huge and elaborate "macaroni wigs" were also popular among some.

Last detail: there was a so-called Macaroni Club in London at the time. It's not clear to me if it was the nickname for a real club, or just a term used to insult English doodles. I've learned that "macaroni" was a disparaging term for a reason you can look up. So actually, if we dig even deeper into Yankee Doodle, it seems to express the British sentiment that the American patriot colonists were a bunch of clueless, unsophisticated, pretentious upstarts, who engaged in conduct that was morally unacceptable at that time.

I find this whole subject highly amusing, in part because like most I learned this song when I was a little child, I heard it everywhere on the 4th of July, and it's considered one of the best known symbols of the USA. But I would wager that most Americans have no idea what it means.

EDIT:

I was just thinking "doodle dandy" is redundant if doodle means dandy. So I checked and according to Wikipedia "doodle" has another meaning: "The term Doodle first appeared in English in the early seventeenth century and is thought to be derived from the Low German dudel, meaning "playing music badly", or Dödel, meaning "fool" or "simpleton"."

I'm out of time or I would look up "dude." I wonder what is meant by calling someone "dude." It seems to be multipurpose, depending on the intonation.
 
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Aufbauwerk 2045 said:
So actually, if we dig even deeper into Yankee Doodle, it seems to express the British sentiment that the American patriot colonists were a bunch of clueless, unsophisticated, pretentious upstarts, who engaged in conduct that was morally unacceptable at that time.
"With the girls be handy.." suggests same.
 
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  • #2,478
I'm catching up on TIL. Here's the last one I can think of for now. Then it's back to work.

I learned something about the life of George Green.

I've watched several videos from the Sixty Symbols channel and enjoyed them all very much.

 
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  • #2,479
Today I learned that anything you see occurred at least 0.25 sec prior to you being aware of it, the time it takes your brain to process the signals from the retina.
 
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gleem said:
Today I learned that anything you see occurred at least 0.25 sec prior to you being aware of it, the time it takes your brain to process the signals from the retina.

I've always wondered how much of your brain's 'processing power' goes into predicting the near future. Not in a tarot card, palm reading, or other magical sense, but in the sense that there's a real delay between receiving signals, processing them, and then acting on them that your brain has to take into account or else you smash into a pole or person coming around a corner or something.
 
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Drakkith said:
I've always wondered how much of your brain's 'processing power' goes into predicting the near future. Not in a tarot card, palm reading, or other magical sense, but in the sense that there's a real delay between receiving signals, processing them, and then acting on them that your brain has to take into account or else you smash into a pole or person coming around a corner or something.

Such a subtle thing that when and where it counts, shows a vast difference in abilities; between me and some pro athlete lol
 
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Aufbauwerk 2045 said:
I wonder what is meant by calling someone "dude." It seems to be multipurpose, depending on the intonation.

lol I suppose that is true for the song Yankee Doodle too. When torn apart, dissected to look at the parts and determine it's meaning ignores the idea it's being sung by average joe and jane American on independence day with cheerful intonation.

For a long time now the song is simply that yankee doodle dandy stuck a feather in his cap and called it macaroni...

pretentious indeed ;)

lol
 
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gleem said:
Today I learned that anything you see occurred at least 0.25 sec prior to you being aware of it, the time it takes your brain to process the signals from the retina.
Once jumping off a 40 foot cliff into a flooded quarry, I was able to feel the wetness of the water contacting me before it registered visually that I was underwater.
 
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BillTre said:
Once jumping off a 40 foot cliff into a flooded quarry, I was able to feel the wetness of the water contacting me before it registered visually that I was underwater.

Nerve impulse from touching travel at about 100 m/sec. So experiencing the sensation of entering the water only takes about 2 msec. Tactile sensations apparently take little time to processes compared to visual processing. From 40 ft it will take you about 100 msec to fully submerge. So you are underwater by the time you get the visual message that you are entering it.

Drakkith said:
processing them, and then acting on them that your brain has to take into account or else you smash into a pole or person coming around a corner or something.

It is generally assumed in determining car stopping distance that the average person takes about 0.7 sec (good reaction time) from the time a situation is realized and the situation is analyzed and addressed. So at 60 mph when you receive the message that needs attention you have already gone 22 ft. Adding to the time it takes to assess the situation and the time that it take to start the braking process you have gone another 61 ft.. Even at 20 mph you have gone almost two car lengths before you hit the brakes.

nitsuj said:
Such a subtle thing that when and where it counts, shows a vast difference in abilities; between me and some pro athlete lol

The more you practice the more an action becomes a reflex not requiring nearly as much processing time An athlete also need a good sense of anticipation of his opponent's next move. It is easier to fake out an amateur.
 
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gleem said:
It is generally assumed in determining car stopping distance that the average person takes about 0.7 sec (good reaction time) from the time a situation is realized and the situation is analyzed and addressed. So at 60 mph when you receive the message that needs attention you have already gone 22 ft. Adding to the time it takes to assess the situation and the time that it take to start the braking process you have gone another 61 ft.. Even at 20 mph you have gone almost two car lengths before you hit the brakes.

When I took driver's ed (so many years ago), it was commonly said that you need 1 car length per 10 miles/hour of velocity to safely stop.
 

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