Archived threads in /sci/ - Science & Math - 223. page

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A single valued relation [math]f[/math] is [math]f\subset A\times B[/math] s.t. if [math](a,b),(a,b')\in f[/math] then [math]b=b'[/math].
How the fuck do I rewrite [math]f[/math] in set form, i.e. [math]f=\{(a,b)\in A \times B|...\}[/math]?
[math]f=\{(a,b)\in A\times B|\mbox{ if } (a,b')\in f \mbox{ then }b=b'\}[/math].
I'm using [math]f[/math] while defining [math]f[/math] which I don't like.
What do?

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Realistically speaking, what's the future of energy generation? Let's say it's year 2100. What method is the most likely to be dominant fusion, fast reactors or simply advancing renewables we have today.

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Can anyone explain to me why [math]\mathbb{R}^2 \nsubseteq \mathbb{R}^3[/math] is true? Surely any plane is contained within the 3D space.

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Let n be a positive integer greater than 5.
Show that the sum of the divisors of n! is not divisible by n!

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Give it a try

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The universe is so incomprehensibly massive,that it would be pretty arrogant of us to assume there isn't some sort of sentient pizza creature somewhere out there.

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> some friends talking about canada
> a guy goes "there's a really big fentanol problem in the tribal communities there"
.> some mishears him
> fentanol
> YEAH FENTANOL
> he keeps repeating it
> i'm on my phone in the corner but I can't bear it and overreact with an icy tone because i often hear this guy trying to talk with authority about drugs when he knows less than nothing
> It's pronounced Fentanyl. Fentan-yl.
> Yeah, whatever man. That. It's killing everyone who takes it. It's really dangerous.
> Another friend asks me what it is (he's a physicist and knows I'm a pharma chemist).
> It's an opioid analgesic roughly two orders higher potency than morphine. It's not that it possesses a unique form of inherent toxicity, it's that the high potency makes measurement haphazard and a shorter half-life can complicate the timing of doses.
> the guy interjects again
> no that's wrong it's like pharmaceutical meth
> stare him down
> Desoxyn is pharmaceutical meth and is prescribed for emergency weight loss. It has no connection to Fentanyl, being from a separate class of drugs that produce observe effects through different mechanisms.
> well it said in the documentary i watched that it was pharmaceutical meth and it's nasty stuff

I felt really dirty and autistic afterwards for responding so aggressively, but it also felt good while I was doing it.

Does anyone relate to this? I get very ambivalent feelings of ride and self-disgust simultaneously when I aggressively bodyslam people not in my field when they try to spread poor quality info on it. Do you think this is a good thing to do to make use of your knowledge and improve that of other people or is it weaponized autism? I do this really often and sometimes I worry that I'm actively looking for opportunities to academically flex. Do you have any similar stories you'd like to share?

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What is the scientific explanation for us gaining aesthetic pleasure from viewing the natural world? For example, by looking at mountains or at the stars at night. By scientific, I mean an evolutionary based explanation.

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When did you finally realize that limits are an ill-defined concept in mathematics?

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If you wave your hand in the air, do the bacteria and viruses on the surface of your hand's skin go flying everywhere or do they cling to the surface?

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did you get accepted by your own merit or because you´re a boy ?

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Is Magnetic Resonance Imaging /sci/ approved?

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Growing up, I was led to believe that smart people are unattractive, and I always held this belief in the back of my mind until I decided to investigate some scientific journals. I thought I was an anomaly or that I just wasn't smart enough to be ugly, but it turns out that smarter people really are more attractive.

So why was there ever a prevailing belief about ugly smart people? What might be the exact pathway between intelligence and attractiveness? And most importantly, why can't I get a gf?
__________

Citations:

>http://www.sciencedirect.com/science/article/pii/S0160289606000353
Negative correlation between IQ and fluctuating asymmetry (FA).

>http://www.sciencedirect.com/science/article/pii/S0160289604000777
Significant positive relationship between intelligence and body symmetry in males.

>http://www.sciencedirect.com/science/article/pii/S1090513809000543
People with higher intelligence aged better, with the metric being FA. The correlation is stronger in facial features.

>http://www.sciencedirect.com/science/article/pii/S0191886906001450
FA and intelligence given a 20% correlation based on a sample of men and women.

>http://www.sciencedirect.com/science/article/pii/S0160289610001315
Beauty in children correlates with IQ based on a sample from the US and the UK.

>http://www.sciencedirect.com/science/article/pii/S0160289614000142
Women prefer men who possess indicators of high intelligence.

>http://psycnet.apa.org/psycinfo/2015-05387-001/
Bodily symmetry in children aged 4 to 15 correlated with both faster reaction times and better cognitive test scores.

>http://psp.sagepub.com/content/28/2/238.abstract
IQ scores correlate with facial qualities, with children judging IQ better than adults.

>https://www.era.lib.ed.ac.uk/handle/1842/6442
Higher asymmetry associated with lower socioeconomic status, slower reaction times, greater senescence, and lower IQ.

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>Graduate with a BSc in Computer Science
>Still don't know how to program

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Okay, I know this sounds like a terrible idea, but hear me out.

Modern locomotives are basically just large diesel generators on wheels. We've already built nuclear reactors small enough, so it's technically feasible. Real R&D will have to be done to see if its economically practical.

The real issue is obviously safety. All of the radioactive fuel spilling into the environment during a crash is an unacceptable risk.

However, I think that risk can be minimized.

A miniaturized Pebble Bed reactor design would be very useful, as the pebble shells would still contain all fission products even if the reactor itself was ruptured. Pebbles ejected upon a collision could easily be tracked down and would not emit immediately harmful levels of radiation by themselves.

Advanced computer modeling and decades of crash testing experience would allow the locomotive itself to be designed such that the reactor vessel would remain intact even in the worst conceivable accident.


Yeah, there's still the problem of convincing the public that this is a good idea, but I'm sure Elon Musk could do it.