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/sci/ - Science & Math

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File: 17 KB, 390x80, concerned scientists.png [View same] [iqdb] [saucenao] [google] [report]
10202516 No.10202516 [Reply] [Original] [archived.moe]

Thoughts on these guys?
I'm reading through some of their articles on minor accidents at nuclear power plants, and while most of the actual content appears to be sound and correct, much of the opinion presented or reporting surrounding the content is full of errors, clickbaity writing that reeks of agenda, and stupid analogies that make me question their credibility.
I checked warosu but nobody ever mentions them or said anything of substance

This is just so I can find it in the archive
Union of Concerned Scientists

>> No.10202520

>>10202516
>This is just so I can find it in the archive
Why not put it in the thread title?

>> No.10202522

>>10202520
Because I'm a dipshit who was thinking about how much I had to piss while writing that post.

>> No.10202536

Who are they affiliated with or sponsoned by?



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10202509 No.10202509 [DELETED]  [Reply] [Original] [archived.moe]

(Pls be gentle, I am a brainlet)

I'm struggling with problem 1 here.

I've put it into the modified Bernoulli equation (accounting for head loss from the sharp-edged exit, k=0.5), taking the top of the tank to be z=0 and the bottom z=-h. After rearranging I've gotten to here:

[eqn]z_1(t)=\int_{0}^{t} v(\tau)d\tau=\frac{v(t)^2}{2g}(\frac{3}{2}{}-(\frac{d}{D})^4)-h[/eqn]

Am I on the right track?

1 replies omitted. Click Reply to view.
>> No.10202518

>>10202509
Wait, ignore the [math]z_1(t)[/math] term, I forgot I divided by the diameter so that's not valid.

>> No.10202521

>>10202509
I dont see viscosity in that equation. Also, where does tau come from?

>> No.10202523

>>10202521
Dummy time variable for integration from 0 to an arbitrary time t.

>> No.10202533

>>10202523
im on my phone cant do algebra to check your work.

>> No.10202568

Wait, should my integral be over z instead of time?



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10202489 No.10202489 [Reply] [Original] [archived.moe]

I need help finding the imedence seen by terminals a and B in the following. It is a practice problem from my book and I don’t know how to solve it without eliminating nodes a and b.

10 replies omitted. Click Reply to view.
>> No.10202846

>>10202550
nah just interested lol

>> No.10202866
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10202866

This is not turning out well

>> No.10202869

>>10202594
is this the same anon that was cooking?

>> No.10202894

>>10202869
I'm not the cooking anon

>> No.10202900

>>10202866
Not sure what you did there
Solving it on octave gives me Z = 4.69 - 0.98j



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10202473 No.10202473 [Reply] [Original] [archived.moe]

How much of a meme is data science? Does a BS in math from a state university with a 3.0 GPA have any hope of landing a job as a data scientist? Not exactly a brainlet but I struggle to work on anything more than 40 hrs a week.

7 replies omitted. Click Reply to view.
>> No.10202695

>>10202500
that sounds like an SQL job for a company

>> No.10202704

>>10202500
Sounds dull

>> No.10203028

>>10202636
That makes sense, but how are outcomes for the business causally tied to your intervention using data?

>> No.10203040

>>10203028
They aren't, which is why there are no job openings

>> No.10203063

>>10203028
Anon, if you were too low iq to know that iq existed, how would you know to increase it?



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10202463 No.10202463 [Reply] [Original] [archived.moe]

how hard would it be to replicate alphazero at home based on the publically available descriptions of its mechanism? any big unknown remainders left that would be too hard to reverse-engineer?

>> No.10202468

>how hard would it be to replicate alphazero at home based on the publically available descriptions of its mechanism?
Why don't you try it and find out?

>> No.10202475

>>10202468
i would assume there's some proprietary original research involved which would be impossible to calculate for a non-expert. so i'm asking /sci/



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10202461 No.10202461 [Reply] [Original] [archived.moe]

Has math changed a lot over the course of nearly 150 years?

https://www.youtube.com/watch?v=KzJjlg3wvew

4 replies omitted. Click Reply to view.
>> No.10202486

>>10202461
She is so perfect

>> No.10202488

>>10202486
How? Her face is so ugly

>> No.10202591

>>10202467
RIP geometric intuition as part of the standard pedagogy
press f to pay respects

>> No.10202606

>>10202461
I don't know about 150 years, but I have an engineering textbook from the 20s covering multivariable calc, ODEs, PDEs, and statistics, and everything is exactly the same as we learn today, except they discuss numerical approximation methods that are obsolete due to computers.

>> No.10202797

>>10202480
No, the derivative of a function used to be calculated geometrically. See: https://www.youtube.com/watch?v=ObPg3ki9GOI&t=115s (1:55)

>>10202591
F



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10202434 No.10202434 [Reply] [Original] [archived.moe]

>feyerabend
thoughts?

>> No.10202441

>>10202434
What is it?

>> No.10202444

>>10202441
who? feyerabend was a philosopher of science

>> No.10202448

>>10202444
Not the text, the snake in the thumbnail.



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10202424 No.10202424 [Reply] [Original] [archived.moe]

Why couldn't we just fill the atmosphere with an aerosol substance and force the world to cool like that, in order to end Global Warming?
If anything, we could just plunge the world into another ice age.

>> No.10202443

NIMBYism

>> No.10202447

>Another ice age would be better than temperatures a few degrees warmer

People on the left shouldn't be allowed to get involved in science, your retarded emotions cloud your judgement and you're ruining everything

Libertarian scientists rise up

>> No.10202451

>>10202424
2nd law of thermodynamics says that in cleaning up one mess, you are actually making a bigger mess somewhere else.

Anyone who tries to sell you things that seem to be too good to be true is a crook.

>> No.10202527

>>10202424
I know. We could use aluminum oxide while claiming it's to reflect out the sun, but we're really just beaming it with phased array radar to heat it up and control the weather.

I know, we could just deploy calcium carbonate in the air and claim it's safe. But when it reacts with UV, it's the ideal environment for us to do other stuff...



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10202407 No.10202407 [Reply] [Original] [archived.moe]

When do you think shit will hit the fan globally in terms of climate change? Like a great worldwide economic depression because of climate disasters.

8 replies omitted. Click Reply to view.
>> No.10202893

Government will take care of it

I just need to vote for the credible man to president and congress

>> No.10202896

>>10202882
>alarmists
>not scientists
Before we had very little understanding of the impacts, and people like Al gore ended up soiling the name climate scientist. Obviously we're going to get it wrong since scientists cant predict human carbon emissions exactly and this has never happened before. The idea that people in the 80 would know what would happen in the 2010s is like giving a final for a class on the first day.

>> No.10203048

>>10202407
>When do you think shit will hit the fan globally in terms of climate change? Like a great worldwide economic depression because of climate disasters.
5 years ago according to Al Gore

>> No.10203056

>>10203048
Are you retarded?

>> No.10203065

>>10203048
9 years ago according to the UN



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10202399 No.10202399 [Reply] [Original] [archived.moe]

One can increase the size of crystals produced in a semi-batch reaction by:
1- decreasing reactant concentrations
2- increasing feeding time(i.e lowering feed-rate)
3-increasing agitation rate
4-increasing mixing intensity at the feed point.

But what might be some drawbacks to making these changes? Thanks if you can help!!

>> No.10202414

There aren't any. Dial all 4 parameters to the end, you get the best crystals ever.

>> No.10202427

>>10202414
some of them might actually not have drawbacks, but I at least know with #3 increasing the agitation rate beyond a certain point will begin to reduce the crystal size u goof

>> No.10202436

>>10202399
hi intro to chem-E idiot.

1. higher flow rate to get same mass yield -> higher capital cost and energy for heating and pumping. higher volume is also a safety risk.
2. similar to 1. need to parallelize to get same mass rate.
3. agitation is energy intensive and hard to scale up. further, agitation competes w/ crystal size because they will break up.
4. see 3.

t. your TA.

>> No.10202453

>>10202436
thank you very much big guy



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10202383 No.10202383 [Reply] [Original] [archived.moe]

I bet I'm a dumbass for not knowing this, but how do you solve this?

23 replies omitted. Click Reply to view.
>> No.10202892
File: 255 KB, 668x3541, solution.png [View same] [iqdb] [saucenao] [google] [report]
10202892

>>10202383

>> No.10202901

>>10202892
>got that premium

>> No.10202925

>>10202892
that is fucking stupid and whoever assigned this to OP or put this in their textbook needs to be gassed

>> No.10202934

>>10202892
Math is beautiful

>> No.10202950

>>10202925
Half of these steps can be made in your head.



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10202359 No.10202359 [Reply] [Original] [archived.moe]

So what is accountable for higher intelligence in people? Nurture aside, there must be a physiological component. What would need to be enhanced for a person to become smarter, if it was possible to do it?

>> No.10202370

The key to making people smarter is to increase their intelligence

>> No.10202373

>pepe
>>>/tv/

>> No.10202848

bump



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10202293 No.10202293 [Reply] [Original] [archived.moe]

>CS is just a meme

Pic related was my final I just turned in, I doubt anyone not in CS could even do it.

29 replies omitted. Click Reply to view.
>> No.10202946

>>10202920
>its been solved by brute force
>eludes researchers
its almost like they arent just looking for an algorithm that will eventually halt, but are instead looking for a more efficient solution. Since brute force takes a really long fucking time

from the website
"The simplicity of the statement of the problem is deceptive -- the TSP is one of the most intensely studied problems in computational mathematics and yet no effective solution method is known for the general case. "

>Secondly, as I already said, the OP post adds more restrictions
But OP's post also lets you have more than one path from city A to city B, so it also takes away the restriction of having only one path for each pair of locations.

>> No.10202966

>>10202293
first of all, let's eliminate the unecessary facts
>drivers leave at 8am
>18mph
>40 packages a day
all irrelevant because the shortest distance is asked, not the shortest time period. yes that also implies that the trucks don't have to be done by the end of the day, since there are no constraints placed on that
>a truck can hold 16 packages
irrelevant since multiple trucks decrease time, but not distance since they all start at the same point

this literally leaves us with:
>find an algorithm for a truck to deliver 16 packages with a minimal distance
which makes it a tsp with n=16 which makes it a retarded and boring problem

>> No.10203038

>>10202920
For n > 10, the problem takes an absurd amount of time. An [math]O(n!)[/math] solution is intractable your computer and certainly mine. Nobody cares about the trivial cases for something around 5-6 cities.

>Hurr durr, a general bound of [math](O,(n^4), O(n^3 \cdot 2^n))[/math] is solved

>> No.10203043

>>10203038
*[math](O(n^4), O(n^3 \cdot 2^n))[/math]

>> No.10203052 [DELETED] 

>>10202966
>but muh [math]\textsc{NP-HARD}[/math}



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10202286 No.10202286 [Reply] [Original] [archived.moe]

Almost everybody here has seen this before, but I'm wondering, what happens if we time reverse it? Does b moving up pull spacetime through the other end of the portal?

>> No.10202305

What if instead of reversing time, you make time go sideways?

>> No.10202310

How about if you turn time in a boat halfway through? What would happen?

>> No.10202320
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10202320

>>10202286
The "time forward" situation is nonphysical to begin with. It is complete nonsense to even ponder it.

>> No.10202531
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10202531

>>10202286

>> No.10202561

>>10202286
Velocity is relative, so saying the space on the other side of the portal is moving relative to the cube is obviously equivalent of saying the cube is moving relative to the space, indicating scenario B.



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10202282 No.10202282 [Reply] [Original] [archived.moe]

I'm going to take acid in 4 days(not my first time), whats the best way to prime my mind with information so I can have a "mind altering trip"?


I'm thinking about reading selected texts all day every day so I'm forced to make connections between the texts and other ideas in my mind

Does priming only work on the daily scale or should I push the date out a couple weeks so I can prime by reading all day for an extra number of weeks?

6 replies omitted. Click Reply to view.
>> No.10202343

>>10202333
just to know if anybody has any knowledge about the priming affect, but I guess i'll do some research on the subject

>> No.10202346

>>10202282
Smoke weed every day.
Call over some hookers

>> No.10202350

Suggested media:
The Metamorphosis, Winnie the Pooh and the blustery day, Peter Zeihan's newsletter.

>> No.10202439

>>10202333
>guy who discovered DNA
I assume you're talking about Kary Mullis and he discovered PCR, not DNA

>> No.10202464

>>10202311
Nah 100 is perfect. 200 is where the real shit begins. Not safe territory.



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10202281 No.10202281 [Reply] [Original] [archived.moe]

I know anonymity makes a person feel free to do whatever shit he wants
>> but it generally tends to go towards more offensive/ aggressive side
>> people do stuff that they won't really do irl unless they're anonymous.
>>So what do they tell you psycho chads what do your studies say.
>> I want to know is that the real human nature to do fucked up shit or is it something that anonymity induces.

>> No.10202674

It is simply truth. The few flowers that bloom in the wasteland gives hope.



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10202270 No.10202270 [Reply] [Original] [archived.moe]

I'm an absolute disaster in Combinatorics. What books and resources are there that cover from the basics (Arrangements, permutations and combinations) to more advanced stuff? I'm relatively O.K. in Calculus and Trig.

4 replies omitted. Click Reply to view.
>> No.10202342

>>10202331
Because I suck at it, and it sucks ass.

>> No.10202725

>>10202270
http://4chan-science.wikia.com/wiki/Mathematics#Primers_in_Combinatorics_and_Graph_Theory

>> No.10203027

>>10202725
>http://4chan-science.wikia.com/wiki/Mathematics#Primers_in_Combinatorics_and_Graph_Theory
Thanks!

>> No.10203050

>>10202270
>What books and resources are there that cover from the basics (Arrangements, permutations and combinations) to more advanced stuff?
Stanley - Enumerative Combinatorics vol 1 and 2

>> No.10203068

>>10202270
Lovasz.



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10202267 No.10202267 [Reply] [Original] [archived.moe]

Anons,
I want to teach you how you can create
a language without using a base language.

Pay close attention to these few pictures,
this is all you need to know for now.

1 - an observation
2 - movement of the observer

What it is when an observer translates
an observation into movement.

1 replies omitted. Click Reply to view.
>> No.10202278

what use is your language between two people who mutually disagree about the nature of every possible observation

>> No.10202285
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10202285

Likely as far as you understand,
a language, mathematics, musical notations, any models..
are specific sets of observations that lead to a specific set of movements -
crucial information when translating languages to another.

I will try to simplify this even further and then come up with the best teaching methods, hopefully this helped some of you at least.

>> No.10202470

>>10202278

I'm not even joking with this one,
but when go further into this topic, "the observation" can be an interaction to the observer you describe as punches,
and these punches and pain make the observer do the things you desire.

Everyone understands pain.

The actions you do after being hurt by "an observation", like a hot stove for example, this fundamentally goes into the same category as words you are reading at this very moment, nice, right?

>> No.10202474

>>10202470
Contrary to your unfounded assertion, not everybody understands pain.

>> No.10202477

D-did you just invent Swedish..??



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10202263 No.10202263 [Reply] [Original] [archived.moe]

Quantum physicists never understood the double-slit experiment from a classical perspective.

I simulated the double slit setup and got an interference pattern with the particles just being hard balls that bounce off walls elastically. One ball at a time worked fine.

I tooled around with the parameter and found only if you take them too the extreme does the pattern disappear.

I've summarized the two approaches to the double-slit experiment in pic related.

85 replies omitted. Click Reply to view.
>> No.10203036
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10203036

>>10203025
ok heres a racist cartoon which is also the solution

>> No.10203042

>>10202263
>This triggers the pop/sci/

>> No.10203060

>>10203015
No, I said that of the particles that get through, the fraction that reflect at all goes roughly as slit thickness divided by source distance. You just never responded to that point because it proves you wrong.

>> No.10203078

>>10203010
They aren't here at pictures with P1 or P2. It's probably from the other slit being covered only partially by the mask so there is still some interference as the mask isn't at point blank from distance from the slits.

>> No.10203086

Nice troll OP, but seriously you haven't disproved jack shit.
First of all, the double slit experiment has always been presented as a thought experiment to illustrate how weird QM is and "wave-like" properties of matter, but having a classical alternative explanation (which you don't have) doesn't explain jack shit about all the other experimental evidence for QM. How on earth do you explain the stern-gerlach experiment, photoelectric effect, the selection rules of hydrogen, Bragg's law, radiation, the whole standard model etc. If you have an alternative explanation for a single Quantum mechanical effect, that doesn't gives you a full working model like QM.
Secondly, obviously you can get that sort of distribution by collision you absolute brainlet, why people are asking you to plug in the actual parameters from an experiment and compare you result is to see if IT FITS EXPERIMENTAL DATA. If you have something that looks like an interference pattern, well that's great, but you need to compare it to the experimental data gathered from the articles already presented to you. Obviously a distribution of initial angles will give you at the end a distribution of final trajectories, this is what classical scattering is all about, but the point here is in that in these experiments they collimate the beam to avoid that noise, and actually get a direct comparison with theoretical models.



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10202251 No.10202251 [Reply] [Original] [archived.moe]

I'm currently in my second year of uni and I want to study math but when I was in highschool I didn't take any calculus, which has effectively delayed my maths education by at least a year. I've gotten an A in every math course I've taken at uni and expect to get an A in multivariable, linear algebra, and proofs this semester, but I can't shake the feeling that I'm a brainlet for not starting my "real" math courses until the spring semester of my second year. How far behind am I compared to the average math major at a mid tier uni?

pic unrelated

>> No.10202254

from the sounds of it, about 1-2 years. no biggie



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