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Watsisname
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02 Sep 2017 17:11

Solaris wrote:
Source of the post One time, a group of dolfins came close to the boat and start playing around it as they like to do, it was night time, and something so eerie happened, as the dolfins swim, the Noctiluca Scintillans is being disrupted and a trail of light appear on and behind the dolfins. I could clearly saw their shape and the path they had took for few short secs, and when they dived deep down, the trail followed. The sea was pitch black and they were moving around in 3d surrounded by this electrical blue sparkling color. They played for few minutes and leaved. it was one surreal and magic moment.

Awesome story -- that surely must have been one of the most amazing of experiences. :) To me I find it an even more powerful than a good aurora display.  Especially since it's so interactive and right there.  No matter how many times I see it, it always startles and slightly unnerves me when I'm going through the pitch black water under a serene starry sky, and all of a sudden the water explodes with these lights.  It's beautiful but also strikes some kind of primal fear, and I imagine what it must be like to be a creature in the deep ocean, content to be in darkness until a glowing nightmare predator materializes right next to you.
 
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22 Sep 2017 21:02

I was in Beijing this week.  I had to present a paper to get it published (IEEE/ICIP2017).  So I went to see a section of the Great Wall, which is compulsory, I guess.  The hike along a non-restored section of the wall was actually much more enjoyable than the restored section which was just crowded.
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23 Sep 2017 00:41

midtskogen wrote:
I was in Beijing this week.  I had to present a paper to get it published (IEEE/ICIP2017).  So I went to see a section of the Great Wall, which is compulsory, I guess.  The hike along a non-restored section of the wall was actually much more enjoyable than the restored section which was just crowded.
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The Great Wall is the only artificial structure you can see from the moon :-)
 
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23 Sep 2017 10:15

A-L-E-X, I don't think that is true, the great wall is long but not wide, our modern cities are far larger artificial structures and you can't even see them from the moon.
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23 Sep 2017 10:26

"Time is illusion. Lunchtime doubly so". Douglas N. Adams
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23 Sep 2017 22:20

For fun let's do the math.  The Moon is about 362,000km away from Earth, at its closest.  The human eye can resolve details down to about 1 arcminute.  At 362,000km, 1 arcminute is about 105km.  The wall is only about 6m wide at its base -- more than 10,000 times too thin to see from the Moon!  There's no way you could spot it with the eye.

What would it take to view it from the Moon?  A telescope at least 30 meters in diameter!

How close would you have to be to expect to just begin to see it?  6m takes up 1 arcminute at about 20km distance.  So the wall is about a factor of 10 times too thin to see from Low Earth Orbit.  That's why specific lighting conditions (like casting long shadows as the Scientific American article reports) are needed to even barely make it out from orbit.

Anyway, @midtskogen those are great photos.  It must have been neat to walk along such ancient architecture -- both restored and not. :)  

I saw the Terracotta Warriors last month when they were on exhibit in Seattle.  It is amazing what people were capable of doing back then under the direction of an emperor like that -- whether for good or ill.
 
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24 Sep 2017 02:16

The wall is narrow, much narrower than a regular 2 lane highway.  However, the length of the wall is much over the resolving limit of 105 km, so one could say that it spans a distance much greater than what can see from the Moon, though the structure itself is far from visible (no more visible than my house). Unlike roads which also span much longer distances, this is a elevated structure, though most of it is now just rubble.  The unrestored section that I walked is from the 14th century, and though the history of the wall goes back much longer, the ancient parts are either replaced or for practical purposes now gone.

The most impressive thing about this wall is its location.  Much is in difficult terrain, and building it without nearby infrastructure is quite an accomplishment.
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28 Sep 2017 10:00

I often use the awesomely intuitive graphing program Desmos. I created a to-scale solar system in it, which utilizes my knowledge of circles, inequalities, and rotation. I kept gradually adding things to it over literal years until it included one star, eight planets, six moons, and five regions of asteroids. I'll make it even more accurate when I figure out elliptical motion.
(Edit: whoops, forgot links.)
(Edit 2: What's wrong with the desmos link?)
Space is very spacious.
 
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28 Sep 2017 11:09

Watsisname wrote:
For fun let's do the math.  The Moon is about 362,000km away from Earth, at its closest.  The human eye can resolve details down to about 1 arcminute.  At 362,000km, 1 arcminute is about 105km.  The wall is only about 6m wide at its base -- more than 10,000 times too thin to see from the Moon!  There's no way you could spot it with the eye.

What would it take to view it from the Moon?  A telescope at least 30 meters in diameter!

How close would you have to be to expect to just begin to see it?  6m takes up 1 arcminute at about 20km distance.  So the wall is about a factor of 10 times too thin to see from Low Earth Orbit.  That's why specific lighting conditions (like casting long shadows as the Scientific American article reports) are needed to even barely make it out from orbit.

Anyway, @midtskogen those are great photos.  It must have been neat to walk along such ancient architecture -- both restored and not. :)  

I saw the Terracotta Warriors last month when they were on exhibit in Seattle.  It is amazing what people were capable of doing back then under the direction of an emperor like that -- whether for good or ill.

That's quite the challenge!  The funny thing is you can actually see people moving around on the ISS through a 9 inch celestron telescope (I posted images of it before on here, a few months back.)

Wat, the ancients were extremely intelligent, the argument has even been made that humanity has seen a reduction in intelligence as its become more specialized (we have seen this in other species too.)  According to these researchers, human intelligence peaked 2,000-5,000 years ago. The researchers said that if you could bring an ancient Greek from that time to ours he or she would adjust much more quickly than taking someone from now and bringing them back to that time.   Just think of the old Greek philosophers, whose scientific principles we still follow today (Aristotle, Archimedes, Plato, Socrates, etc.) and where democracy originated (Democritus.)  Remember the finding of the Antikhera device?  What an amazing ancient computer it was- and to think there might have been many more just like it whose blueprints were lost because of the corrupt Augustus who chose to destroy the library at Alexandria.  I hated the Romans with a passion because of their conquering ways (which the rest of western civilization has inherited from them) but also because of how they stole from the Greeks, and what they did to the Library and to Carthage.
 
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28 Sep 2017 12:25

A-L-E-X wrote:
Source of the post The researchers said that if you could bring an ancient Greek from that time to ours he or she would adjust much more quickly than taking someone from now and bringing them back to that time.

Sounds dubious, as we have much knowledge of antiquity whereas the ancients have no knowledge of the modern world.  Unless you mean adjust to the other level of comfort of living.

A-L-E-X wrote:
Source of the post Just think of the old Greek philosophers, whose scientific principles we still follow today (Aristotle, Archimedes, Plato, Socrates, etc.)

Actually, we don't follow their scientific principles, but we do acknowledge their contributions to what are today's principles.

A-L-E-X wrote:
Source of the post the corrupt Augustus who chose to destroy the library at Alexandria.

Where do you have that idea from?

A-L-E-X wrote:
Source of the post I hated the Romans with a passion because of their conquering ways (which the rest of western civilization has inherited from them)

Well, war was normal back then.  If fact, war was a quite legitimate political tool until about WWI.  You must judge from a contemporary viewpoint.  The concept of citizenship for conquered lands was an innovation, and the Romans were able to keep a relative pax Romana for over two centuries from Augustus to Marcus Aurelius, which is remarkable.

A-L-E-X wrote:
Source of the post but also because of how they stole from the Greeks

Stole?  Romans greatly respected (much of) Greek culture.
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28 Sep 2017 14:06

midtskogen wrote:
A-L-E-X wrote:
Source of the post The researchers said that if you could bring an ancient Greek from that time to ours he or she would adjust much more quickly than taking someone from now and bringing them back to that time.

Sounds dubious, as we have much knowledge of antiquity whereas the ancients have no knowledge of the modern world.  Unless you mean adjust to the other level of comfort of living.

A-L-E-X wrote:
Source of the post Just think of the old Greek philosophers, whose scientific principles we still follow today (Aristotle, Archimedes, Plato, Socrates, etc.)

Actually, we don't follow their scientific principles, but we do acknowledge their contributions to what are today's principles.

A-L-E-X wrote:
Source of the post the corrupt Augustus who chose to destroy the library at Alexandria.

Where do you have that idea from?

A-L-E-X wrote:
Source of the post I hated the Romans with a passion because of their conquering ways (which the rest of western civilization has inherited from them)

Well, war was normal back then.  If fact, war was a quite legitimate political tool until about WWI.  You must judge from a contemporary viewpoint.  The concept of citizenship for conquered lands was an innovation, and the Romans were able to keep a relative pax Romana for over two centuries from Augustus to Marcus Aurelius, which is remarkable.

A-L-E-X wrote:
Source of the post but also because of how they stole from the Greeks

Stole?  Romans greatly respected (much of) Greek culture.

The Romans had a conquering philosophy which inherently detest and they treated other people viciously- Pax Romana was achieved by conquering and destroying other cultures first  (which is something the British and French followed when they went to Asia and Africa.)
The Romans (from Caesar to Aurelius) were absolutely responsible for the destruction of the library at Alexandria, problem is that Western culture still has that warlike philosophy (just look at the US interventionist philosophy of the past few decades.)  Look at Carthage and how they bared the Carthaginians of their clothing and destroyed all their villages.  Hannibal in contrast was far more civilized when he conquered the Romans and the locals hated the Romans so much that they sided with him against them.  The Romans, like the cowards they were, holed themselves up behind a wall, to avoid having to face Hannibal.

The Library at Alexandria was burned down several times, but the Romans did it first and most frequently.

http://www.bede.org.uk/library.htm

All the Romans did was change the names of the Greek gods and goddesses and okay you can say they borrowed, but like Taleb said, the Greeks were far superior to the Romans because the Greeks were the creators, not the Romans.
https://news.ycombinator.com/item?id=1797536
Can someone explain "A Greek among Romans" from Taleb's homepage?
Benoit Mandelbrot, 1924-2010 A Greek among Romans



harscoat 2539 days ago [-]

It seems that Taleb wants to separate Mandelbrot, a sophisticated, educated, refined, and übersmart person, from the rest of the crowd.

As far as intelligence is concerned, I just don't believe we have the ingenuity to do what the ancients did with what they had available to them- like the antikythera device.  We are far too dependent on technology which does our thinking for us.  Nor could we have built the pyramids or any of those other great archaeological marvels like Stonehenge.  And remember that the Greeks created the scientific method, modern geometry and astronomy (created the magnitude system and the Pythagorean theorem and the Archimedes principle).

https://en.wikipedia.org/wiki/Antikythera_mechanism
https://www.livescience.com/37095-human ... umber.html
https://www.livescience.com/24713-human ... gence.html
In November 2012, Stanford University School of Medicine researcher Gerald Crabtree published two papers in the journal Trends in Genetics suggesting that humanity's intelligence peaked between 2,000 and 6,000 years ago.

Crabtree based this assertion on genetics. About 2,000 to 5,000 genes control human intelligence, he estimated. At the rate at which genetic mutations accumulate, Crabtree calculated that within the last 3,000 years, all of humanity has sustained at least two mutations harmful to these intellect-determining genes (and will sustain a couple more in another 3,000 years). Not every mutation will cause harm — genes come in pairs, and some weaknesses caused by mutation can be covered for by the healthy half of the pair, Crabtree wrote; but the calculation suggests that intelligence is more fragile than it seems.

Furthermore, he argued, intelligence isn't as evolutionarily important to humans today as it was when the species was hunter-gatherers. Thousands of years ago, failing to grasp the aerodynamics of throwing a spear when a lion was coming at you meant you were toast — no more passing along your genes to offspring. Modern man rarely faces such life-or-death tests of wits, Crabtree wrote. [10 Things That Make Humans Special]

Another theory holds that humanity's genetic capacity for intelligence is in decline because of a phenomenon called dysgenic mating. Since the mid-1800s, IQ and reproduction have been negatively correlated, studies have found. To put it bluntly, people who are more intelligent have fewer babies. Because intelligence is part genetic, some researchers argue that, if anything, IQs should be dropping.

Instead, scores are going up, creating a paradox for the dysgenic mating theory, Woodley said.  

Understanding an intelligence paradox

Now, Woodley and his colleagues think they may have solved that paradox, and the news is not good. 

To look back at historical intelligence, the researchers turned not to IQ tests, but to reaction time. Simple reaction time (the amount of time it takes to respond to a stimulus) is correlated with IQ, Woodley said, and not nearly as sensitive to cultural influences as IQ tests.

"The idea is that reaction times represent your ability to engage in very basic and elementary cognitive processing," he said. [The 10 Best Ways to Keep Your Mind Sharp]

In the 1880s, English scientist Sir Francis Galton measured reaction times in 2,522 young men and 888 young women from a wide variety of socioeconomic statuses. He found that men's average reaction time to a stimulus was 183 milliseconds, and women's was 187 ms. (Galton's reaction time studies were part of his work as the founder of the field of eugenics, the idea that only the "best" should reproduce. Eugenics was embraced by a variety of high-profile people in the early 1900s, most notably Adolf Hitler, who wanted to establish a "master race" of Aryans.)

Twelve similar studies to Galton's conducted after 1941, on the other hand, found an average reaction time for men of 250 ms and for women of 277 ms — markedly slower. A review study detailing those findings was published in The American Journal of Psychology in 2010.

Woodley and his colleagues expanded on the 2010 work, including additional data and matching the old and new studies to be sure they were measuring the same things. Despite the fact that timers have improved quite a bit since the 1880s, Woodley is confident that Galton's measurements are accurate. Galton used a pendulum-based machine to time reactions, and such machines are generally accurate within 10 ms, Woodley said.

Galton's data also behaves as you might expect it to behave if it were correct, Woodley said. For example, groups with more inbreeding performed worse on the reaction time test.

The new analysis was "crystal clear," Woodley said.

"We found a very, very robust trend with time, toward slowing speeds of reaction," he said, "which is consistent with the idea that the more stable, the more culturally neutral, the more genetically influenced components of intelligence have been declining rather than increasing."

What that suggests is that even as IQ scores rise with education and health, humanity's capacity to get smarter is shrinking. In essence, the Flynn effect might be hiding an underlying decline, a "psychometric dark matter" not visible on pen-and-paper intelligence tests, Woodley said.

"An analogy to use would be lower-quality seeds, but higher-quality fertilizers," he said, referring to this idea that a high-quality environment may be masking the decline in "smart" genes.

If true, the reasons are unknown. Possibilities range from exposure to neurotoxins in modern society to natural selection.

Smarter or dumber?

Not everyone sees the new reaction time findings as the final word, however.

"To sum up 100 years of research, there is a reliable correlation between measures of reaction time and measures of IQ, but the order of such correlations is far short of what would be required to use the former to explain the latter," said Theodore Nettelbeck, a psychologist at the University of Adelaide who researches intelligence.

In other words, Nettelbeck told LiveScience, using reaction time as a proxy for IQ leaves something to be desired. At best, he said, reaction times to complex stimuli might explain about 20 percent to 25 percent of the variation in IQs, and simple reaction times explain a lot less.

Nettelbeck also raised concerns about the various experiments analyzed in the new study and how comparable they might be.

"Not only would there be differences in the technologies for timing responses, which may or not influence the outcome measures; there would also be procedural differences in the numbers of trials from which means [averages] have been derived, instructions to participants, extent of prior practice, the nature of stimuli, the form of response keys, all of which can influence the length of response," he said.

Reaction time can also be tricky to interpret, said James Flynn, for whom the Flynn effect is named.

"A dull person has just as quick a peak reaction time as a brilliant person," Flynn told LiveScience. The difference is that someone with a low IQ typically can't stay focused and so their reaction times won't be consistent throughout an experiment; their scores vary more widely than those of high-IQ people.

"Is this really neural speed, or for a dull person, [or] is it much more difficult for them to be attentive to the task?" Flynn said.

Other factors play a role as well, he added. In studies of schoolchildren, kids in Hong Kong are quicker off the mark in reaction time tests than British kids. You could read those results to mean Chinese kids are smarter than Britons, Flynn said. Or perhaps Chinese kids are just more willing to take risks.
 
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28 Sep 2017 15:46

Nothing super impressive, saw a mantis outside on the window and wanted to take a few pictures
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28 Sep 2017 18:46

Mantises are pretty awesome and a big reason I am glad I am not an insect.  Or a male mantis.
 
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28 Sep 2017 23:21

Alex,

That was a long post full of misconceptions and biased opinions.  You must understand antiquity on antiquity's terms to some degree.  The Roman conquering philosophy had benign aspects that other nations did not have.  The Romans allowed the conquered to preserve their religion and culture to a relatively large degree.  Partly because the Roman religion was pretty broad in the sense that Romans essentially assumed that all gods were the same, but simply went by different names and different ways of worship (so when you suggest that they stole the Greek gods and simply changed their names, you're totally misunderstanding their religion).  And partly because allowing the conquered to keep their ways, and even grant them new rights as Roman citizens, was a fairly successful assimilation tool.  Please tell me how other nations of antiquity conquered clearly better.  What about the Greek?  The most aggressive conqueror of the period was undoubtedly Alexander the Great, but that was somehow not as bad as Roman expansion?

If you apply a modern view, it does not look good to invade your neighbours, but it doesn't make sense to pass such judgement on events 2000 years ago.  If so, you shouldn't be praising people like Pythagoras either, whose school was a wacky cult.

They only thing I'd like to comment about the rest of your post is that before the Greek, there were Babylonians, Egyptians, Phoenicians and others.  Geometry, arithmetic, etc didn't start with the Greek.
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29 Sep 2017 03:27

midtskogen wrote:
Alex,

That was a long post full of misconceptions and biased opinions.  You must understand antiquity on antiquity's terms to some degree.  The Roman conquering philosophy had benign aspects that other nations did not have.  The Romans allowed the conquered to preserve their religion and culture to a relatively large degree.  Partly because the Roman religion was pretty broad in the sense that Romans essentially assumed that all gods were the same, but simply went by different names and different ways of worship (so when you suggest that they stole the Greek gods and simply changed their names, you're totally misunderstanding their religion).  And partly because allowing the conquered to keep their ways, and even grant them new rights as Roman citizens, was a fairly successful assimilation tool.  Please tell me how other nations of antiquity conquered clearly better.  What about the Greek?  The most aggressive conqueror of the period was undoubtedly Alexander the Great, but that was somehow not as bad as Roman expansion?

If you apply a modern view, it does not look good to invade your neighbours, but it doesn't make sense to pass such judgement on events 2000 years ago.  If so, you shouldn't be praising people like Pythagoras either, whose school was a wacky cult.

They only thing I'd like to comment about the rest of your post is that before the Greek, there were Babylonians, Egyptians, Phoenicians and others.  Geometry, arithmetic, etc didn't start with the Greek.

In some ways, the US gets compared to the Romans- it's not really a compliment.  The Romans had their share of authoritarian dictators who did horrible things (Octavian, Caligula, Nero).  They also treated the Carthaginians horribly when they stripped them naked and burned down their cities, and it's true that when Hannibal invaded and freed the locals, they chose to side with him because the Romans had treated them so poorly.  Speaking of biased opinions, did you know that the Romans also had the habit of destroying historical texts and trying to alter texts so it would benefit them and make them look good?  I don't support any power-hungry entity that does these things.  Alexander the Great was Macedonian (not technically Greek, but I guess he can be considered as such), and he had some bad qualities too, but he also sought to spread knowledge and combine cultures (he intermarried with various nobility he met on his journeys.)  I suppose you could consider him on the same level as The Romans (only much more powerful, since he did it all in his lifetime, and it took the Romans much longer- Alexander, who was educated by Aristotle, Plato and Socrates, is considered the greatest general in recorded history.)  Speaking of which, Cleopatra (who was a descendant of Alexander's) had children with Julius Caesar (so they were descendants of both Alexander the Great and Julius Caesar.)  After his death, she got involved with Marc Antony (who I consider one of the "good" Romans), unfortunately Octavian with his inferiority complex of being an "adopted" son of Julius's decided to murder the entire family including the children (or would have but they committed suicide.)  Didn't like Octavian either- Marc Antony was one of my favorites.

What did you think of the research about how intelligence may have changed with time?  It's a complicated subject.
Well, I'm only praising Pythagoras about his contributions to mathematics! Yes those other cultures were also very advanced ( I believe the concept of zero actually started in India.)   The Carthaginians were actually Phoenicians (and the most advanced sailors on the planet at the time- as a matter of fact after the Romans burned down Carthage, it was rumored that the remnant Carthaginian population took to boats and fled across the seas to South America, and some evidence of their presence was found in artifacts and architecture in the tropical rain forest of Brazil.)  In reference to the Greek vs Roman comparison, what I meant was that the Greeks are viewed as being extremely inventive and creative, and the Romans not so much.  Probably because they had a military society.  The Romans had no one on the level of Aristotle, they had no Plato or Socrates either.  That is why Taleb said what he said about Mandlebrot and said he was "a Greek living among Romans."  I pass judgment on killing (so it applies to the British and French and Americans too- look at what was done during "colonization"- it would be considered war crimes today, and actually still is being done in the Middle East)  but not on other things like what was common back then (which would be considered child abuse today.)
By the way, on another topic, did you get to see any of the northern lights tonight?  It was AMAZING.  Don't know if it was as spectacular out your way, but from the northeast US down to about Iowa and even out west to Seattle, it was a spectacular display (and of course Canada got some of the best views- naked eye and right overhead!)
Wat, did you see anything out your way?
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