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Science

"Virtually all mammals experience REM sleep. However, REM sleep is a risky time, because it renders animals paralyzed and helpless. To make matters worse, during REM sleep the body consumes nearly as much energy as when it’s awake, which is a marked contrast to the other, thriftier stages of sleep. This suggests that REM has some fundamental importance, or a superior race of non-dreamers would have evolved millions of years ago"

Intuitive explanation of “Brownian motion”

Consider a large balloon of 100 metres in diameter. Imagine this large balloon in a football stadium. The balloon is so large that it lies on top of many members of the crowd. Because they are excited, these fans hit the balloon at different times and in different directions with the motions being completely random. In the end, the balloon is pushed in random directions, so it should not move on average. Consider now the force exerted at a certain time. We might have 20 supporters pushing right, and 21 other supporters pushing left, where each supporter is exerting equivalent amounts of force. In this case, the forces exerted towards the left and the right are imbalanced in favor of the left; the balloon will move slightly to the left. This type of imbalance exists at all times, and it causes random motion of the balloon. If we look at this situation from far above, so that we cannot see the supporters, we see the large balloon as a small object animated by erratic movement. Consider the particles emitted by Brown’s pollen grain moving randomly in water: we know that a water molecule is about 0.1 by 0.2 nm in size, whereas the particles which Brown observed were of the order of a few micrometres in size (these are not to be confused with the actual pollen particle which is about 100 micrometres). So a particle from the pollen may be likened to the balloon, and the water molecules to the fans, except that in this case the balloon is surrounded by fans. The Brownian motion of a particle in a liquid is thus due to the instantaneous imbalance in the combined forces exerted by collisions of the particle with the much smaller liquid molecules (which are in random thermal motion) surrounding it.

Brownian motion on Wiki

Basically, Brownian motion of a body is what happens when a very large number of similar forces act on the same body from all possible directions. If the forces were uniform and applied at the same time to the body then there wouldn’t be any movement but since there are slight differences in the direction, strength and time of application of the forces, the body begins to move like in the simulation below of a large dust particle (yellow) experiencing brownian motion due to collision with the smaller gas molecules around it.

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The clever thing is that the same can be said of stock price fluctuations where millions of tiny trading exchanges between people (small brown gas particles) push the stock price (large yellow dust particle) into a form of Brownian motion called Geometric Brownian motion. Hundreds of billions of dollars are moving similar to the lowly dust in the air around you right now. Self-similarity, once again.

This is what a human heart looks like in the earliest stages of development of a human baby.

matthen:

The smooth motion of rotating circles can be used to build up any repeating curve even one as angular as a digital square wave. Each circle spins at a multiple of a fundamental frequency, and a method called Fourier analysis shows how to pick the radiuses of the circles to make the picture work. Decomposing signals like this lies at the heart of a lot of signal processing. [more] [code]

They should teach this in schools, right?

"There are 10^11 stars in the galaxy. That used to be a huge number.
But it’s only a hundred billion. It’s less than the national
deficit! We used to call them astronomical numbers. Now we should
call them economical numbers."

Richard Feynman

Wait, why isn’t the clock hand moving?

Chronostasis is the illusion in which the first impression following a saccade (quick eye movement) appears to be extended in time. The most well-known version of this illusion is the stopped-clock illusion, where the first movement of the second hand of an analog clock, following the viewer’s directing attention to the clock, appears to take longer than the next movement.

Experiments have shown that this illusion is probably caused by the way in which the brain attempts to construct a continuous consciousness experience in spite of saccades.Although this effect is present with all eye movements, it is most noticeable when an external time-keeping source is observed.

Here’s a whole bunch of stuff you didn’t know about the Angler fish

“He Loves Me, He Loves Me Not… “: Uncertainty Can Increase Romantic Attraction

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You know all those TV shows and movies and anime where the guy and girl never say what they feel and this drags on to the point of insanity and you’re like “JUST TELL IT ALREADY DAMMIT!!”? Turns out that pointless, annoying dilly-dallying is actually beneficial to the success of the relationship. 

This research qualifies a social psychological truism: that people like others who like them (the reciprocity principle). College women viewed the Facebook profiles of four male students who had previously seen their profiles. They were told that the men (a) liked them a lot, (b) liked them only an average amount, or (c) liked them either a lot or an average amount (uncertain condition). Comparison of the first two conditions yielded results consistent with the reciprocity principle. Participants were more attracted to men who liked them a lot than to men who liked them an average amount Results for the uncertain condition, however, were consistent with research on the pleasures of uncertainty. Participants in the uncertain condition were most attracted to the men—even more attracted than were participants who were told that the men liked them a lot. Uncertain participants reported thinking about the men the most, and this increased their attraction toward the men.

So next time you fall in love, don’t tell them right away. Tease them with your uncertainty till they (and all who observe) end up in a mental asylum ‘cause apparently that’s how humans work (doing this increases the time the target thinks of you leading to higher chances of a favorable response). Marlon Brando employed this strategy in his life and he was quoted approaching friendships as a spider tackles its prey; he moves closer, pulls back after a while and then moves closer again thus slowly weaving his target into his web.

The whole process, to me, is very convoluted but knowing the reason for why this strategy seems successful makes it a bit more palatable. If I have to give an anology, this strategy of maintaining ucertainty is like a dance and dance is way more harder and absolutely pointless when the goal is simply to move from point A(strangers) to point B(relationship) when compared to just walking straight from A to B. Yet dance is undeniably more memorable and interesting than just marching from point A to point B. Guess it’s the same deal here, when it comes to human relationships the memorable and more interesting “uncertainty” approach has a higher success rate than the straighforward approach.

(Of course, the rich and the famous and the beautiful have no need for these convoluted strategies, these are mainly for normies like you and me.)

Leptin and weight loss

Your body keeps track of how much fat you have through a chemical called leptin and makes you hungry if you’re starting to lose weight. Thus, if you skip a meal in the morning, it’ll be sure to make you extra hungry in the evening, so that your overall weight doesn’t change.

Aaron Swartz

Why eggs were beaten in copper bowls

Eggs were often beaten in copper bowls. Why copper bowls? Chefs might have been able to give you some kind of reason, but it would have sounded silly to scientific ears. But the modernists discovered that the ions in the copper ended up forming complex bonds with the conalbumin in the eggs.

- Aaron Swartz, co-founder of Reddit

The reason why copper bonding with conalbumin is desirable is that the conalbumin-copper complex is more stable than the conalbumin alone, so egg whites whipped in a copper bowl are less likely to denature (unfold).

"No one knows exactly why yawning is contagious, although many theories have been posited — including the idea that yawning cools the brain and increases alertness, helping entire groups to become vigilant if one individual yawns."

"Everything you’ve learned in school as “obvious” becomes less and less obvious as you begin to study the universe. For example, there are no solids in the universe. There’s not even a suggestion of a solid. There are no absolute continuums. There are no surfaces. There are no straight lines."

Richard Buckminster Fuller

Tractors and User Interfaces

The designers of the Phelps farm tractor in 1901 based their interface on a metaphor with the interface for the familiar horse: farmers used reins to control the tractor. The tractor was steered by pulling on the appropriate rein, both reins were loosened to go forward and pulled back to stop, and pulling back harder on the reins caused the tractor to back up

I finally figured out the rule-of-thirds

After months of wrestling with understanding the science behind the art of composition, just 30 seconds ago while watching this video, I had a moment of epiphany when it all became clear. 6 minutes and 28 seconds into the video, there’s a shot of polar bear lying on the ground and the shot is composed according to the rule-of-thirds with the polar bear positioned in the lower-right. So far, so good. But then the bear starts to get up and that’s when it all clicked into place.

Putting a subject dead-center in the frame limits the amount “whitespace” around it making the photo feel “claustrophobic’. Instead we put the subject in one of the four corners of the 2D plane of the photo. Since putting the subject exactly at, or too close to a corner makes it feel claustrophobic again, we give the subject a bit of a margin from the nearest corners and edges and these 4 locations corresponding to each corner form the positions on the rule-of-thirds window.

I should have caught on to this from the simple fact that there are four locations where subjects can be placed as per the rule-of-thirds window and there are also… you guessed it, four corners — it’s easy to see the rule-of-thirds window is closely related to the corners of the photo. Had I seen this earlier, the rest  understanding that the rule-of-thirds is merely a framing method to give appropriate amount of “whitespace” for the subject to “breathe” in  would’ve been a piece of cake. Instead it took me months of head-wringing to finally see the light. 

So, putting the subject in the dead-center of a photo is like standing inside a tiny-cramped cage while framing the subject using rule-of-thirds is like standing inside a humongously large cathedral. There are some subjects that look better in tiny cramped spaces and thus suit the dead-center framing while the others look better in cathedral-like spaces and thus suit the rule-of-thirds framing.

What benefit do we get from understanding the rule-of-thirds is just a way to give the subject “whitespace”? Simple! We can now bend it and break it to create new compositions because once we understand that framing is all about allocating whitespace around the subject, we are freed from the strict 4 corners of the rule-of-thirds window and now a wide variety of interesting locations and compositions become available to us since we can roam all around the photo looking for just the right amount of whitespace to give to the subject of that particular shot. 

This last part, where to use what amount of “whitespace” is still an art for me. I have some clues but some day I’ll nail the science behind the art of “whitespace” like I did today with rule-of-thirds.

freshphotons:

Chemical etching can spontaneously transform a flat silicon surface into one consisting of nanoscale facets, a process that covers the surface with tiny pyramids. Via.

freshphotons:

Chemical etching can spontaneously transform a flat silicon surface into one consisting of nanoscale facets, a process that covers the surface with tiny pyramids. Via.