Today I Learned

  • Thread starter Thread starter Greg Bernhardt
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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.
  • #3,751
mfb said:
For some reasons your 5 cent coin is larger than the 10 cent coin, and apparently 50 cent is larger than 1 dollar as well.
Well at least we don't have any coins with holes in them... :wink:

1621524970706.png

https://en.wikipedia.org/wiki/Japanese_yen
 
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  • #3,752
Oh! There used to be a spanish coin with a hole in it pre €uro days. Maybe the 25 peseta coin, if I remember rightly.
 
  • #3,753
mfb said:
Is the half dollar actually used?
There are 1 dollar coins.
https://en.wikipedia.org/wiki/Dollar_coin_(United_States)

For some reasons your 5 cent coin is larger than the 10 cent coin, and apparently 50 cent is larger than 1 dollar as well.
Historically, the dime, or 10 cent coin, was made of Silver, while the 5 cent coin is made of Copper and Nickel.

Coinage pretty much disappeared during the Civil War, and it wasn't until after it that the US started minting coins again, starting with Bronze 1 and 2 cent coins. They then minted a 3 cent Copper-Nickel coin.
The five cent "nickel" was minted based on the earlier success of the Copper and Nickel 3 cent piece. It ended up replacing the earlier Silver half-dime.
 
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  • #3,754
mfb said:
Is the half dollar actually used?
Canada has/had a 50 cent coin - but the only time it was ever seen in the wild was at the Canadian National Exposition. All the games cost 50 cents and the barkers would give you back a 50 piece from your dollar.
 
  • #3,755
Like regular cirrus clouds, contrail cirrus clouds have two competing effects on climate. They shade us by reflecting incoming sunlight back into space. But they also trap heat radiating from the earth’s surface, so causing warming in the air below.

During the day, cooling compensates part of the warming. But at night, with no sunlight, only the warming effect operates. Red-eye flights are a red light for climate. That’s the theory, and observational evidence backs it up. Research in the American South and Midwest has concluded that when contrails are around, they raise night-time temperatures sufficiently to reduce the day-night differences by 3 degrees C.
https://e360.yale.edu/features/how-airplane-contrails-are-helping-make-the-planet-warmer
 
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  • #3,756
berkeman said:
The term dropping the dime, in criminal parlance, has long meant to (usually anonymously) rat out a fellow criminal (whether an accomplice or an enemy). The phrase (most likely) refers to an anonymous tip placed by dropping a dime (as was the cost throughout much of the latter 20th century) into the slot of a payphone, and then making a quick anonymous call to the police, tipline, DA or whomever.

Additionally, a 'dime' is also a ten year prison sentence.

--diogenesNY
 
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  • #3,757
Two kinds of things are celebrated in Today I Learnt. One is the striking or curious interesting fact the writer didn't know and probably you didn't either. The other is the more rueful discovery where the surprising fact is that the writer didn't know it. Maybe these need another thread called "Only today I learnt".

I have known something about Whistler since age 9 or 10. This came from one of the phenomenally successful 'William' childrens' books by Richmal Crompton aimed at a readership of about 9 to 12 range. Which sold over 12 million copies and are still in print if rather dated and. The equivocation on which the line of the story where I learned (and of which I don't remember much else) depends is that a very prosperous member of the local community has acquired a Whistler which is the talk of the town, but the anarchic and rather ignorant antihero William supposes that a Whistler is some kind of machine that whistles. Instead it referred to a valuable painting.So thanks to the book I knew what a Whistler was early on, but I didn't know much more for a long time. I don't remember reading about him in books about painting I read, nor in books of reproductions of famous painters I once had. Many decades later I did come directly across some works – Whistler's most famous and striking painting of his mother in the Orsay museum, Paris https://www.wikiart.org/en/james-mcneill-whistler then some other works in the Hunterian Museum, Glasgow. https://www.gla.ac.uk/whistler/ https://www.gla.ac.uk/whistler/thehunterian/ And every now and then in general reading over the years, mostly I guess in cultural pages of newspapers, I stumbled across mentions of Whistler. Yet I often had a uncomfortable feeling, a cognitive dissonance , there was something not quite right I could never put my finger on. Might it be him being called an "American painter"? An American painter? Like there was more than one? :oldbiggrin: Sorry folks, in Europe we hardly know of a single one before about 1930. And the categorisation 'American' is problematic - he was indeed an American citizen but he spent fairly few years in the USA, though he did attend West Point, where he was a total misfit. Most of his painting was done in Britain and France. Unusual but there was still something else uncomfortable though… I was always very uncertain about his dates and things said soeti sounded incongruous (I didn't even know till today much of what I've said or linked to above).

Now, if you haven't heard, there has broken out in Britain over about the past year acutely a massive movement in the arts, museums and heritage curation sector, around public monuments, in culture the arts and in the universities, the sciences by no means exempt, broadcasting, and journalism, to revise, revalue, and change everything in the names of e.g. 'decolonising the curriculum', awareness raising, wokeism, revising, re-relabelling, re-evaluating, BLM, 'culture wars', re-examining our national identity, history, and self image. After this movement has washed over many more obvious targets, in about the last fortnight the immorality of Isaac Newton and George Friedrich Handel who held investments in companies involved in slave trading have in their turn been brought into focus by this movement (it is no merit of Sir Isaac's that he lost a lot of money over it) and it will probably become obligatory to mention this in University lectures when Newton's discoveries are explained. In the very last days another piece of heritage to now give offence after having been in place for about 100 years are the Whistler murals in the Tate gallery in London. To see this sort of discussion Google rex whistler tate mural.

100 years? The Tate? As I said I had been vague about Whistler and vague about dates, but had uncomfortable feelings. So I thought I must look into this at last.

And not before today I learnt that there have been two famous painters called Whistler.

The first was the one discussed above named James Whistler (which is cutting a long story short actually). The second, who occasioned the present furore was Rex Whistler. He "painted many members of London society, including Edith Sitwell, Cecil Beaton and other members of the set to which he belonged that became known as the "Bright Young Things". "

The general idea of Bright Young Things is obvious, and I knew that it was rather attached to the interwar period, but only today I learnt that it originally referred to a very specific group. And there is no doubt that the Whistler of the William story would have been Rex. Williams's older brother and sister, Robert and Ethel who come into the story would surely have wished or affected to be Bright Young Things.

I really do not know why the painting contains the things objected to. I first thought it might be irony, and ironic comment on the sources of wealth of the better off Bright Young Things or perhaps of the philanthropists who financed the Tate. But it is possible that he merely found the fantasy, the conceit, of 'The Expedition in Pursuit of Rare Meats' amusing. The Bright Young Things were fashionable and bohemian, but they were not progressive and were seriously unserious. And snobs. Supercilious and superior, finding everything and everyone perfectly amusing. One can even find much to condemn in them if one wants to take seriousness towards the opposite extreme.

That said one should not forget that Rex Whistler died fighting in the war against Nazism.

https://www.spectator.co.uk/article/why-has-the-tate-cancelled-its-own-restaurant-

https://en.wikipedia.org/wiki/Tate_Britain

https://en.wikipedia.org/wiki/Rex_Whistler
https://artuk.org/discover/artists/whistler-rex-19051944
 
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  • #3,758
epenguin said:
Maybe these need another thread called "Only today I learnt".
The standard phrase is "I was today years old..."
 
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  • #3,760
berkeman said:
Well at least we don't have any coins with holes in them... :wink:
Having cash is better :wink:
 
  • #3,763
https://www.yahoo.com/lifestyle/known-carcinogen-found-popular-sunscreens-130300895.html

Known carcinogen found in some popular sunscreens, tests show​

Traces of a chemical tied to blood cancers including leukemia have been detected in dozens of popular sunscreens and after-sun products, according to tests conducted by online pharmacy and lab Valisure.

Benzene, a known carcinogen, was found in 78 of nearly 300 sprays and lotions tested — about 27% — including products sold by Banana Boat and CVS, according to Valisure.

In a petition, the company has asked the FDA to recall these contaminated batches. The regulating body is reviewing the claim.
 
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  • #3,764
“lovely little old rectangular green French silver whittling knife.” Think about it: You cannot move the order of those adjectives at all without having the sentence seem completely wrong.
I haven't tried all 8! perms.
From "Inc." via Firefox Pocket
 
  • #3,765
TIL that the electronics term wobbulator is spelled with 2 b's. Many years ago I worked with some terrific engineers where security concerns required mainly verbal (even whispered) instructions; so, I did not see the word in print. We modified pulsed radar transmitters to wobbulate output in such a manner to defeat enemy counter-measures (ECM); i.e., ECCM. I meant to study the subject after returning to university but was stymied by lack of information due to my spelling error.

Radar transmit/receiver (TX/RX) tracking devices synchronize operation via common distributed timing pulses. Aggressor aircraft learned to read (clock) the timing pattern and spoof receivers with bogus but powerful returns at critical interval before we locked on weapon systems. Wobbulating the local synchronizer isolated the radar in a sense from the enemy RX/TX spoofers. The radar synced as usual and presumably the enemy recognized an RF source in the vicinity but an attached O'scope and the enemy saw a wicked sliding series of incoherent RF pulses.

I thought of this modified synchronizer circuit as wobbulating time. Different wobbulators alter wavelength and thus bandpass, particularly of klystrons; mentioned in the attached articles.
 
  • #3,766
Klystron said:
particularly of klystrons
Gee. And all this time I thought you were a real person.
 
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  • #3,767
Forensic facial reconstruction on a skull shaped vodka bottle:
Full sequence here.

Screen Shot 2021-06-13 at 12.32.43 PM.png

Eyes don't come with bottle.

Screen Shot 2021-06-13 at 12.33.10 PM.png


Screen Shot 2021-06-13 at 12.33.39 PM.png


Screen Shot 2021-06-13 at 12.34.14 PM.png
 
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  • #3,768
_nc_ohc=FMLBAQQrpmoAX8e1lff&_nc_ht=scontent-ham3-1.jpg
 
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  • #3,769
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  • #3,770
pbuk said:
Well that is one theory.
It made sense to me. We have a similar expression that is used in daily language and almost nobody knows that it stems from the military. We use 08/15 as an adjective with the meaning 'quick and dirty' for any occasion when simple solutions or answers are used that are not necessarily reliable.
There are several explanations of the idiom, which are related to the machine gun 08/15. 08/15 stands for the introductory year of the original model MG 08, 1908, and for 1915, the year of further development. These numbers were slammed into the weapons.
 
  • #3,771
Today I learned the word querulant, meaning someone who persistently complains about minor injustices, often increasing demands as their requests are met so that it is impossible to satisfy them. They are something of a problem for complaints departments, since they suck up time with no possibility of a successful outcome.

https://en.wikipedia.org/wiki/Querulant
 
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  • #3,772
Ibix said:
Today I learned the word querulant, meaning someone who persistently complains about minor injustices, often increasing demands as their requests are met so that it is impossible to satisfy them. They are something of a problem for complaints departments, since they suck up time with no possibility of a successful outcome.

https://en.wikipedia.org/wiki/Querulant
While previously familiar with the word querulous, TIL from @Ibix 's reference that paranoia querulans appeared in medical publications as a valid psychiatric diagnosis. Originally restricted to members of Karenus Complainus Americanus, the term now embraces a considerably larger swath of the population. /humor
 
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  • #3,773
Ibix said:
Today I learned the word querulant, meaning someone who persistently complains about minor injustices, often increasing demands as their requests are met so that it is impossible to satisfy them. They are something of a problem for complaints departments, since they suck up time with no possibility of a successful outcome.

https://en.wikipedia.org/wiki/Querulant
Congrats, you learned a German word.
 
  • #3,774
Klystron said:
Originally restricted to members of Karenus Complainus Americanus, the term now embraces a considerably larger swath of the population.
The wiki article actually comments that querulant was retired from official use for some time because the term got broadened to mean "anyone who complained about anything", where it originally meant "someone who obsessively complains far beyond the point a normal person would". The context I learned it in was the same thing happening with "Karen" (with the added bonus of Karen being a gendered term with no male equivalent with anything like the popularity).
fresh_42 said:
Congrats, you learned a German word.
Congrats, you stole a Latin word, I think...
 
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  • #3,775
Ibix said:
Congrats, you stole a Latin word, I think...
Yes, but it doesn't feel like it. Queruant is not as exotic as it is in English, it is part of common language. And we also have quer as a regular adjective, meaning: perpendicular to a given direction.
 
  • #3,776
Ibix said:
Congrats, you stole a Latin word, I think...
I think that there is a rule somewhere that forbids native English-speakers from becoming querulant about any such perceived offense. Something about glass houses.
 
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  • #3,777
A funny word is window. While the English word is from "wind-open" and of Nordic and therewith Germanic origin, we use Fenster which is fully Latin: Fenestra.
 
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  • #3,778
fresh_42 said:
Yes, but it doesn't feel like it. Queruant is not as exotic as it is in English, it is part of common language. And we also have quer as a regular adjective, meaning: perpendicular to a given direction.
We have queer, which has its roots in the German quer. It used to mean out-of-kilter or strange before being adopted as a term for homosexuality (it was used as a euphemism of sorts, but got "reclaimed" as an accepted term).
jbriggs444 said:
I think that there is a rule somewhere that forbids native English-speakers from becoming querulant about any such perceived offense. Something about glass houses.
Oh sure, English doesn't so much borrow words from other languages as mug them at gunpoint.
 
  • #3,779
Ibix said:
Oh sure, English doesn't so much borrow words from other languages as mug them at gunpoint.
I was trying to work a "schadenfreude" gag in there somewhere but I couldn't see it. You may enjoy my discomfort at my failure in any language you please.
 
  • #3,780
My personal favorite is Torpenhow Hill. It's etymology is like all of English history in a nutshell. Kind of like a core sample but for language. Also worth a good laugh!
 
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  • #3,781
Ibix said:
We have queer, which has its roots in the German quer. It used to mean out-of-kilter or strange before being adopted as a term for homosexuality (it was used as a euphemism of sorts, but got "reclaimed" as an accepted term).
We have quer in all variations: Querbalken for a beam e.g. above a door, Querstraße for a street which goes of a main road to the side, newly "Querdenker" which is the euphemism people call themselves if they are against the given order, or the duty to wear masks, mainstream news, etc. I don't think that any of them ever thought (denken), Querlenker for the steering bar of a bicycle or a control bar, Querschnitt for a slice of something or a representative subset, Querung for crossing e.g. a river, and probably many more. Hence Querulant is simply another example of the many variations to quer (as in opposition to along).
 
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  • #3,782
fresh_42 said:
Querstraße for a street which goes of a main road to the side
Of all of those, I think English only has Queer Street, and it's an informal (and mostly archaic) saying meaning trouble - to be "up Queer Street" means to have had things go wrong.
 
  • #3,784
Ibix said:
Of all of those, I think English only has Queer Street, and it's an informal (and mostly archaic) saying meaning trouble - to be "up Queer Street" means to have had things go wrong.
I had a discussion with my sister today about the many words that cannot really be translated. My favorite examples are still "schweigen" and "sophisticated". "Schweigen" is an active verb, we decide to do something, namely being silent, but we are not silent. It is a decision, an act, and not a state. You cannot translate it. As you can't translate "sophisticated". You can translate all manifestations of it with varying adjectives, but you cannot get a hold on its universal property.
 
  • #3,785
TIL how to convert a 3-D model into line-art in Blender in a few easy steps.
Example:
Start with a model, such as this one of a X-wing(shown here as a full render)
xwing3d.png

Create a new "Grease pen" object.
Apply the "line art" modifier to the Grease pen, assigning the model as the "source.
Make a couple of choices regarding line color, thickness, etc.
Render. That's it.
You might want to change the background, depending on what you are going for. For example, here I replaced the stars with a plain white background, which gives it a more "Drawn on paper" vibe.
x_wing_line.png

There are a whole bunch of other options/settings you can use to optimize things, and you can remove any unwanted lines ( I see a couple in this example that could be cleaned up)

It's a neat alternative to photo-realistic renders and offers a bit more artistic flair.
 
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  • #3,786
fresh_42 said:
A funny word is window. While the English word is from "wind-open" and of Nordic and therewith Germanic origin, we use Fenster which is fully Latin: Fenestra.
Or "wind eye". Apparently it was first a hole in a roof.
https://www.etymonline.com/word/window
 
  • #3,787
epenguin said:
Or "wind eye". Apparently it was first a hole in a roof.
https://www.etymonline.com/word/window
It was also a hole in the wall. It took considerably long until window shields were established north of the Alpes. "eye" is a euphemism for holes. Open has a similar heritage and I wouldn't bet that "-ow" is from "eye" rather than from "open / offen".
 
  • #3,788
fresh_42 said:
A funny word is window. While the English word is from "wind-open" and of Nordic and therewith Germanic origin, we use Fenster which is fully Latin: Fenestra.
English retains the Latin word for window in the technical word defenestrate, meaning to be thrown out of a window. Although the definition includes throwing any object from a window, I have only seen it used in English to describe a human body, with the connotation of an execution or bad accident.
 
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  • #3,789
First time I have heard this story

In March of 1694, L’Hospital wrote to Bernoulli, then back in Basel, offering him an annual pension of 300 livres in exchange for help with mathematical questions and a promise to send to L’Hospital mathematical results which L’Hospital could then publish under his own name. What today we call L’Hospital’s rule was sent by Bernoullli to L’Hospital later that year. In 1696, L’Hospital published the very first book on calculus, Analyse des infiniments petits, pour l’inteligence des lignes courbes, which Fred Rickey has translated as Analysis of the Little-Bitty-Guys for the Study of Curved Lines. Here is the first recorded mention of what today we call L’Hospital’s rule. Bernoulli’s lectures from 1691–92 would be published in 1922, revealing that much of L’Hospital’s book was first discovered by Bernoulli. In fact, after L’Hospital’s death in 1704 with Bernoulli now freed from his contract, he laid claim to L’Hospital’s rule as his own result.

from
Appendix to A Radical Approach to Real Analysis 2nd edition 2006 by David M. Bressoud
 
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  • #3,790
Johann Bernoulli just to be accurate, since there was also Jacob, his elder brother.
 
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  • #3,791
TIL how to pronounce the name "Desiree". I saw it for the first time and thought it was some weird Gen Z name pronounced like "retiree" o:)
 
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  • #3,792
TIL that there are several species of nocturnal soft furred tree mice, in china, that are able to echolocate.
This adds to the list of those mammals (insectivorous bats and toothed whales) known to echolocate.
 
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  • #3,793
BillTre said:
TIL that there are several species of nocturnal soft furred tree mice, in china, that are able to echolocate.
This adds to the list of those mammals (insectivorous bats and toothed whales) known to echolocate.
At least there won't be public suspicion on virologists for starting the next pandemic, it'll be neuroscientists.
 
  • #3,794
Amazon Prime Day is upon us. I found this interesting, sad, and gross:
“People are running through stop signs, running through yellow lights. Everybody I knew was buckling their seatbelt behind their backs because the time it took just to buckle your seatbelt, unbuckle your seatbelt every time was enough time to get you behind schedule,” said Adrienne Williams, who drove for an Amazon DSP from November 2019 to July 2020. . .

Drivers told us that poor routing practices have led them into dangerous situations and left them no time to find a bathroom.

“Now that’s why some people are urinating in cups and everything and plastic bottles,” Williams said. “They just kind of leave them which is definitely disgusting, getting into the vans the next day and seeing somebody’s pee bottle sitting behind the seat or sitting in the cup holder.”
https://www.cnbc.com/2021/06/21/dri...ressures-of-delivering-for-an-amazon-dsp.html
 
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  • #3,795
kyphysics said:
Amazon Prime Day is upon us. I found this interesting, sad, and gross:

https://www.cnbc.com/2021/06/21/dri...ressures-of-delivering-for-an-amazon-dsp.html
Your amazon drivers always deserve a good review (if amazon in your country asks for this) and probably a tip as well.

(There were stories in the press about drivers who received less than perfect reviews being obliged to do extra training and sometimes losing their jobs. )

I try to avoid amazon as far as possible. Buying from independent sellers on ebay who use other delivery methods - even sometimes regular post - is an alternative.
 
  • #3,796
rsk said:
Your amazon drivers always deserve a good review (if amazon in your country asks for this) and probably a tip as well.
Most of my deliveries are positive, but I've had some bad ones occasionally too.

For example, it's raining and I posted a big sign to put the package inside a cooler on the front porch, so as to avoid getting it wet. The person literally put the package an inch from my cooler, where that big sign was posted. I know they are allowed to put it into my cooler, b/c I've asked for that before many times and it's always done. This one time it's raining hard and the driver puts it outside (literally about an inch or less from the sign and cooler).

I've had a huge item that was fragile come in a smashed box with the bottom opened up. Not sure if it was the driver's fault to be fair...but that was a bad delivery for me.
 
  • #3,797
Yeaaaah, if I had to pee in a bottle to keep my job, I'd feel like punting the packages at the houses.

I'm curious here: why is it that amazon's treatment of its workers is so much worse than other delivery services? Are the profit margins for amazon and, say, UPS that different?
 
  • #3,798
This is scary:
The number of Americans who are homeless has increased in each of the past five years, according to government data, and for the first time more than half of homeless adults are living not in shelters but in tents or sleeping bags outside. There has yet to be a nationwide homelessness count since the start of the pandemic, but a quarter of Americans now report being at “imminent risk” of losing their homes, and cities up and down the West Coast say they are overwhelmed by an unprecedented rise in homeless people, hazardous encampments and related trash.

This month, as Portland announced plans to start removing more camps, the city said it has gone from having an average of about six large encampments before the pandemic to what it now estimates to be more than 100.

https://www.washingtonpost.com/nation/2021/06/12/homeless-camps-portland/
 
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  • #3,799
Scary and sad. We have lost our way as a species I think :(
 
  • #3,800
Today I learned watched that what "Theory of Everything" means is the combining of the four forces.
- Gravity
- Electromagnetism
- Strong force
- Weak Force
I mean, I've known this four forces years ago, and I've heard about this TOE, but just yesterday I leaned that it's the combination of the four forces.
Not "learned" is the right word. Because I still have no idea about the combining of these forces.
But I can imagine that 200 years ago before Faraday people didn't know that electricity and magnetism were actually the same force. I just take electromagnetism for granted.
And if this guy, Kaku san, and also Einstein, Hawking (and may be Brian Greene?) try to understand the universe by reducing everything into four forces only, I can't help thinking that 2000 years ago Aristotle tried to reduce the world into four elements.

"In 15,000 years we have invented nothing!" - Picasso on cave painting in southern France.

 
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