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cygnus_a

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MAD is the future. And righteousness is the enemy. Don't mess with us. Don't mess with them.

Also, do the world a favor, and don't innovate new weapons. They leave an indelible affect on the collective mind.

i vote we change the name. "generalized quantum mechanical phenomena maybe" ... and we can rename quantum gravity to "generalized macroscopic versions of quantum phenomena maybe"

then we can add the "maybe" suffix to all the rest of our theories

What a lame article title.

The actual article presents evidence that Americans are getting more comfortable with self-driving cars, and points out that peoples' concerns aren't very valid.

Honestly, I almost didn't read the article because of the title. Fortunately there was a tiny fit of rage in me that clicked to see what the author actually was saying.

This is one of the main reasons I support legalization and/or decriminalization of all drugs. Demand is demand, and a black market economy is worse than a transparent & regulated economy.

I think it's still necessary to focus on reducing demand (through education and self-help, not punishment).

As you might know, turbulence is when simple streams of laminar flow (in say, plasma) turn into chaotic filaments and vortices. As a filament or vortex separates/stretches from your laminar flow region, it steals away heat/energy.

Scientists often assume that you can accurately approximate stuff by neglecting irrelevant parts of the physics (basketballs vs ping pong balls; protons vs electrons). Turns out that ping pong balls greatly affect the outcome and amount of heat/energy dissipation in the basketballs.

This doesn't surprise me too much, since critical behavior often happens in regimes where two separate aggregate effects become relevant. But the details are all still just a big mystery :)

P.S. someone posted a much better description than the OP. I'll reiterate: http://news.mit.edu/2016/heat-loss-fusion-reactors-0121

I agree that teaching mathematics too formally prevents students from making concrete connections. I like how the OP made the abstractions intuitive. And made the jargon less intimidating.

As far as the 'mathematician's lament' goes though, I think all that is needed is for our culture to foster greater respect (and potentially payment) for teachers. If someone can put passion into their work, these successes tend to arise naturally.

Math is hard for the same reasons that anything is hard. It is literally a mental strain on your brain.

I agree with the author in that a teacher's enthusiasm and perspective, and 'rigidity' in school can compound difficulties.

But as a physicist, the most difficult part of learning math, for me, is overcoming my own mental barriers. I need patience and focus to comprehend even the most simple sentences. If I don't want to learn/strain in the moment, then I won't.

I think there are two valid existential concerns regarding AI:

1) Widespread use of advanced AI in robotics/production has the ability to bankrupt the working populace, at which point something closer to pure socialism may take over; not so much an annihilation scenario.

2) AI is weaponizable -- at a certain point, given other technological advances in addition to AI, a relatively small amount of like-minded people will be able to produce unique weapons of mass destruction.

for me it's more like... boobs? why'd they put boobs in the thumbnail? the article isn't even... I ... I might as well see if there's a bigger picture of the boobs

In other words, not using racial preferences in admissions decisions lets the black college enrollment trends continue; though, as the article doesn't point out, 'not using mandated racial preferences (banning aff. action)' is not the cause of disproportionate representation.

I think the argument against affirmative action is more, morally speaking, addressing the question, "should we use racial preference to fight racial preference?".

I often have intense fantasies about conversations with personal mentors, historical figures and/or deities (what would Buddha say? How about Einstein? etc). Obviously I can't reproduce their thoughts, but knowing a little about them, I can try to think like them

Surely they're not as visceral or reflexive as the author's voices. But I have always found value in empathizing with fantasized mentors, which has given me confidence in my opinions.

There were a lot cultural misses in Walmart. For instance, nobody bags your groceries in Germany. When you're not expecting it, it's fucking weird to have some employee come up and grab your food.

Also, Germany has places like Kaufland and Rewe (in addition to Aldi) that have certain items much cheaper than Walmart. I found that milk, rice, bread and cheese were all cheaper there than in the US... and better quality for some reason too.

The TLDR intuition of a change of basis is this: you have a vector of length L that points from the origin up towards the z-axis. If you'd like to rotate your perpendicular measuring sticks like x->x', y->y' and z->z' (ie, rotate your coordinate system, maintaining perpendicular-ness and vector length), then you've changed your basis. Say you rotate your coordinate system 90 degrees about the y-axis, now your vector points in the new x-direction (so x-> -z, y->y and z->x, and your vector is (1,0,0) instead of (0,0,1)).

You can do that with a matrix operation (M*v = v'):

[0 0 1]___[0__ __[1

[0 1 0]___0__=__0

[-1 0 0]__1]__ __0]

In fact, this matrix rotates any vector 90 degrees about the y-axis.

Basis vectors can also be more abstract than that. For instance, they're useful in quantum mechanics for simplifying the schroedinger eq (sometimes from a second order diff eq to a first order one) by changing from a position basis to a momentum basis, in effect rewriting your derivatives from a different point of view.

It doesn't surprise me how much water there is in the solar system, considering how simple of a chemical water is. Life itself is a chemical reaction that takes much longer to complete (though I'm starting to think that it's more abundant than I think :P).

For future reference, fusion happens in stars (and at the center of supernovas). H combining with O2 is a chemical reaction rather than a nuclear reaction.

On the other hand, the question regarding how supernovas combine/mix heavy atoms to form chemicals would be a very interesting PhD thesis. :D