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/sci/ - Science & Math

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8699444 No.8699444 [Reply] [Original] [archived.moe]

What's the superior way to write k-hat?

2 replies omitted. Click Reply to view.
>> No.8699706

>>8699444

I think the best k-hat is no k-hat, if you're really autistic about it then use \widehat{k}:
[math]
\widehat{k}
[/math]

>> No.8699716

So how do you write l-hat then?

>> No.8699720

>>8699716
hat:
[math]
\hat{l}
[/math]
widehat:
[math]
\widehat{l}
[/math]

>> No.8699721

>>8699720
But shouldn't the hat be to the right of the vertical line if the OP pic is correct?

>> No.8699723
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8699723

>>8699444
why do physics autists put hats on letters instead of themselves?



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8699440 No.8699440 [Reply] [Original] [archived.moe]

I can't wait for the day when overdue geomagnetic solar superstorm completely destroy's the world's electric network.

It will the day the internet dies.

It will be the day smug tech billionaires commit suicide worldwide as their automation, snapchat, twitter, normiebook and electric car memes die.

It will be the day when people will finally be free to go out and meet/talk to real people like they used to for thousands of years before the internet scourge.

It will be the best day of your life.

>> No.8699446

go away /x/

>> No.8699449

>>8699440
>It will be the day when people will finally be free to go out and meet/talk to real people like they used to for thousands of years before the internet scourge.
But have you ever done that though?



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8699436 No.8699436 [Reply] [Original] [archived.moe]

Pic related are in my self-study holster. Are they terrible? Is there better? Recommendations pls.

Also /textbook/ general.

6 replies omitted. Click Reply to view.
>> No.8699492

What's a good introductory book for Magnetohydrodynamics (MHD)?

>> No.8699549

>>8699436
Hartog is the man!

for any major not pure mathematics, the best book is KA stroud engineering mathematics and advanced engineering mathematics.

Been using them since first year, now in an MSc and still using them

>> No.8699550

>>8699441
I can tell you never actually read a book. Reading off screens is fucking horrible.

>> No.8699577

>>8699436
oh look, another book collector thread

>> No.8699616

>>8699441
reading a book is a million times nicer but i can't quite pinpoint why



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8699359 No.8699359 [Reply] [Original] [archived.moe]

Scientifically speaking, what would be the most efficient method of rasing or otherwise collapsing a civilisation with regards to minimising energy and resources spent?

18 replies omitted. Click Reply to view.
>> No.8699540

>>8699532
Great but I doubt very many of that calibre would come here. They've probably already got a good job and life back there. It's just the fat, swarthy, inbred ones that come here.

I've seen huge families of them just sat around on benches with their brood of ugly kids swarming around, generally making nuisances of themselves.

I've also seen similar scenarios outside houses. Again, about 15 of them just hanging around on the pavement getting in the way.

At all hours of the day, too. They don't seem to have jobs to go to but they've managed to wangle themselves a house.

I've seen plenty of Poles, Slovaks, etc working hard. I've literally encountered TWO working Romanians in Britain. One of whom was a student (came over here before the country was even in the EU).

At the end of the day, if Romania was a good as you reckon, then there'd be hundreds of thousands of us going over there every year to live.

Difference is that the locals there would probably rise up and petrol bomb them to oblivion.

>> No.8699566

>>8699528
Except people would realise they were under attack.

The best way is to play the long game and do it slowly, so the target has no idea that this is an attack.

Isn't Mossad's motto basically that?

>> No.8699630

>>8699533
yeah seriously
biological or chemical weapons would probably be by far the most cost effective and quick way of killing nearly everybody

>> No.8699707
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8699707

>>8699424
>>8699430
/leftypol/ is not and has never been SJW. Intersectionality and identity politics are diametrically opposed to Marxist thought and their concept of "privilege" is unscientific voodoo not tied to any objective factors in the real world. Obvioisly it distracts from the only REAL privilege, which is whether you own the means of production or not.
>i.e. spot the pants on fire, /pol/ cancer

>> No.8699736

Feminism



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8699351 No.8699351 [Reply] [Original] [archived.moe]

If I killed myself by shooting myself through the roof of the mouth, would I hear the shot before dying? Or would I be off to DMT heaven before then?

7 replies omitted. Click Reply to view.
>> No.8699453

>>8699422
yeah what the fuck is wrong with your taste in women?

>> No.8699467
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8699467

>>8699453
If a bitch ain't a Kim or a Park,
I wouldn't fuck her -- Even in the dark.

>> No.8699647

You would hear it, but you wouldn't register it.. I think.

No expert, but with some common sense, the bullet would take you out before you had any time to realise what that sound created by the gun was.

>> No.8699652

>>8699647
Then again, I'm unsure what sort of an effect speed of sound vs. speed of bullet would have as the distance between the sound source and recepient is very little.

>> No.8699696

Just do the heaven thing instead



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8699332 No.8699332 [Reply] [Original] [archived.moe]

Is Isaac Arthur any good, /sci/?

https://www.youtube.com/channel/UCZFipeZtQM5CKUjx6grh54g



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8699271 No.8699271 [Reply] [Original] [archived.moe]

ITT name the course/subject you had the most difficult time with

Also, what advice would you give yourself back when you were still in undergrad

Me
>toughest course = Calc I and III (pls no bully)
>advice to myself: probably would be to devote more time to conceptualize. Spent too much time memorizing specific approaches and formulas instead of understanding how and why, did robot mode for 4 years

Also easiest course was humanities related classes

2 replies omitted. Click Reply to view.
>> No.8699325

>>8699315
yeah I wasn't saying the early courses are actually tougher information. tougher stuff comes later, but you learn how to approach the subject from different angles thanks to the general courses.

for people who were brainlets in their early courses, they'll have a much harder time later on.

>> No.8699343

Currently doing Signal processing.
first half of the course of Fourier analysis, second half is filters and wavelets.

>> No.8699358

>>8699343

signal processing would be a breeze if you learned the math beforehand.

you don't do laplace?

>> No.8699366
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8699366

For me the toughest by far was 'Approximation Algorithms' (MSc level course). Basically, given some optimization problems, we were required to come up with approximation algorithms that are guaranteed to give a solution which is within some given factor from the optimal solution, and then prove that it works correctly. The algorithms themselves were easy as fuck, but the proofs tend to be absolutely brutal.

>> No.8699450

>>8699366
>proofs tend to be absolutely brutal
this, but applied to all my courses that require proofs.
I'd feel like I get the material but would freeze up on test day



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8699254 No.8699254 [Reply] [Original] [archived.moe]

Can science ever give a complete picture of reality when it deliberately ignores qualitative aspects of reality and only acknowledges quantitative aspects of reality?

>> No.8699257

>>8699254
Can dumb animeposters ever cease their shitposting

>> No.8699262

No. That's why metaphysics exists.



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8699237 No.8699237 [Reply] [Original] [archived.moe]

What do you do if you're a brainlet who can't understand basic algebra?

3 replies omitted. Click Reply to view.
>> No.8699284

>>8699237
i just kill myself and start over again, You totally have to try it out yourself! Works for me every time.

>> No.8699288

>>8699279
hey i'm doing khan academy too. i didn't study anything math related for about 6 years, and then realized i had to learn a few things for the military ASVAB. it's the hardest when you have nothing to hold on to, but the shit gets easier and easier. drink some coffee, put on some good music and smile, you'll get it. you definitely aren't alone.

>> No.8699419

>>8699279
I believe in you, anon!

but believe in me too...

>> No.8699421

>>8699419
fuck, spoilers don't work here?

>> No.8699809

>>8699237
Vote for Trump



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8699222 No.8699222 [Reply] [Original] [archived.moe]

Why isn't it infinity? Or 1?

46 replies omitted. Click Reply to view.
>> No.8699814

1+2+3+4...=-1/12
0+1+2+3+4...=-1/12
(1+2+3+4...)-(0+1+2+3...)=((1-0)+(2-1)+(3-2)+(4-3)...)
(-1/12)-(-1/12)=(1+1+1+1...)
0=(1+1+1+1...)=(((math is a jewish trick)))
1+1+1+1...=infinity
0=infinity
infinity/infinity=1
0/0=1

checkmate atheists

>> No.8699824

>>8699814
woah...so this...is the power...of Post-Anabelian Froeboid Geometrics

>> No.8699838

>>8699278
>>8699281 (you could've just disproved the x=1 by using 0=x*0 instead)
>>8699725

Only sensible people in this ITT thread.

>> No.8699856

because theres a shit ton of functions who's limit evaluates to 0/0 but have different answers

>> No.8699866

If 0/0=x, then 0=0*x. Since x could be any number, 0/0 is not defined, for if it were, then every number would equal 1 or infinity or etc.



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8699220 No.8699220 [Reply] [Original] [archived.moe]

Hi /sci/

I'm interested in logging the highest and lowest temperature of a shipping parcel, for example, to know if it has been exposed to subzero temperatures.

Usually this is being done with a temp sensor, low power microcontroller and a battery. However, this is fairly complex and expensive.

I'm wondering, isn't it possible to do some kind of passive logging with a molecular sensor? I'm thinking of a protein for example that changes molecular composition irreversibly when exposed to certain temperatures.

Does this already exist? What are the keywords to search for?

I'm an electrical engineer, and not really familiar with the biochemical field.

Thanks for any tips and tricks!

1 replies omitted. Click Reply to view.
>> No.8699264

>>8699220
Put something in that breaks something and changes color when it reaches freezing? Like, I dunno, a little fragile packet of water under pressure that'll burst if it expands from freezing, releasing some trapped dye? I'm sure this has been done...

>> No.8699298

>>8699220
We use a wax pellet thing to detect high temperatures.

>> No.8699411
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8699411

>>8699220
>temp sensor, low power microcontroller and a battery
totally absurd

>> No.8699438

>>8699220
Thermochromic inks

>> No.8699445

>>8699220
Im this guy>>8699438

Look into food packaging technology, specifically active and intelligent packaging. Refer to Principles of Food Packaging 3rd ed by Gordon Robertson

I dont know how you would think embedding proteins into your package/inside package would be less expensive or complex than a microcontroller set up you mentioned.

t. Foodscience fag



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8699171 No.8699171 [Reply] [Original] [archived.moe]

What if the internet spans parallel dimensions and all of the flat earther/climate denier brainlets live on a planet that is actually flat and not experiencing drastic changes in temperature?

>> No.8699173

>>8699171

That'd be fucking hilarious.

>> No.8699175

>>8699171
Then we must enter into their dimension and enslave them all.



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8699122 No.8699122 [Reply] [Original] [archived.moe]

I know /sci/ prides itself on not being /x/...
all that aside, What conspiracy theories does /sci/ think could be semi-plausible? Provide credible evidence where possible. Just curious.

22 replies omitted. Click Reply to view.
>> No.8699428

>>8699243
Pretty much this >>8699245
There is no """true equality""" and there never will be as long as humanity lives. Humans aren't born with the traits to create equality or even believe in it. Its just a nice catchphrase to make you feel good.
Fact is, rich people will live better than you, people in better neighbourhoods will live better than you, people who are born more attractive than you will live better than you, people that are white and you aren't will live better than you. People with friends will live better than you(having friends is also dependant on the previous things I stated) Etc. etc.
Its better to fukin ignore equality or any politics that revolve around it, same with right wing politics. They're all fucking bullshit, instead of wasting time with that, do something useful for once and try to build something for humanity instead wasting time on """muh feels are hurt u rascitst!!!!! D:""" and """muh national pride being washed away by the evil jew D:"""

>> No.8699469

>>8699428
Fairly certain inequality evolves in any situation where it doesn't exist to start with. It's basic social instinct to form hierarchies. Rich debutants in high schools form cliques, all have access to nearly everything they could ever desire, and yet you still see a clear pecking order among them. I suspect the same would be true even among a group of human clones (and tends to be the case among identical twins).

That's not to say that part of the function of society isn't to attempt to uplift the less fortunate though, and in more modern ones, maximize opportunities for everyone.

But it's a fine line... And entirely off topic.

...Unless you wanna get into the grandest true conspiracy - that power simply collects power, like gravity.

>> No.8699470

>>8699428

> Humans aren't born with the traits to create equality or even believe in it.
Of course they do. Even monkey do. Blatant inequality is something we naturally disaprove.

And it is also a fact that having a more equal society brings more happiness to pretty much everyone.

>> No.8699495

>>8699469
>But it's a fine line... And entirely off topic.

The conspiracy is to make people believe they are entitled to the money they earn " because muh market is right"

>> No.8699503

>>8699122
>>8699122

I think the failed coup in Turkey was staged by their president.



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8699113 No.8699113 [Reply] [Original] [archived.moe]

so if acceleration is constant, then velocity is linear, and distance covered is nonlinear.

but if you have change in acceleration that's constant, acceleration is linear, velocity is nonlinear, then what's the distance covered? super nonlinear?

how do you form relations of linearity from higher order derivatives? this is so stressful you don't understand. i can't grasp how one can state whether the acceleration or velocity of a system is linear if nothing is known other than a few terms like the distance covered because it could be nonlinear, but how nonlinear?

>> No.8699537

>>8699113
Either something is linear or it non-linear, there is no other thing.

The derivative of distance is speed, the derivative of speed is acceleration.

If you know the functions to any of these terms (and they are sufficiently nice) you can calculate the rest.

Most importantly if any of these are linear all before that are non linear, so if acceleration is linear speed will be non-linear, and when speed is non-linear distance is non.linear.


And if you understood what the term "linear" and the term "derivative" mean you would have no problem understanding that.

>> No.8699588

"non-linear" doesn't describe the behavior very well. When acceleration is constant, position changes as t^2 which is parabola. If acceleration wasn't constant, then it depends on what the expression of acceleration is. If acceleration is linear, theb velocity will be a parabola and position will be something of t^3.



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8699106 No.8699106 [Reply] [Original] [archived.moe]

>mathematicians are smarter than physi-

3 replies omitted. Click Reply to view.
>> No.8699119
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8699119

>>8699117
>>8699111

>> No.8699142
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8699142

>>8699119
>tfw accountant

>> No.8699154
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8699154

>>8699106
>averages
No

>> No.8699184
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8699184

>>8699106
>Social Work
>Education - Early Childhood
>Education - Counselling
>Home Economics
>Education - Special

>> No.8699190

>>8699106
average is dragged down by stacies who just want to be teachers



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8699079 No.8699079 [Reply] [Original] [archived.moe]

[eqn]\displaystyle \zeta \left( \sum_{k=1}^{\infty} \frac{9}{10^k} \right) = \zeta(1) = \infty[/eqn] Therefore, [math]\displaystyle 0.999\ldots = 1[/math]

2 replies omitted. Click Reply to view.
>> No.8699138

>>8699108
>lmfao anime damsel you are high AF right now
nope, you are you fucking brainlet

>> No.8699144

>>8699138
you just took an infinite series and then concluded that 0.999...=1 now go back to your shit gween tea cartoon.

>> No.8699181

[eqn]\zeta(-4)=\zeta(-2)=0[/eqn]

Therefore, [math]-4=-2[/math]

>> No.8699525

>>8699079
W-what are you trying to say?

are you seriously implying that f(x)=f(y) => x=y is true?

>> No.8699535

>>8699108
>>8699144
fucking brainlets

>>8699525
yes. the only pole of the riemann zeta is 1



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8699048 No.8699048 [Reply] [Original] [archived.moe]

How many of you guys work at interesting locations for your various scientific (or non-scientific) jobs? And if you do work at an interesting or remote location where is it at and what do you do there? The Antarctic, under the ocean, remote mines, any place that you hazardous place that you won't find many people at.

5 replies omitted. Click Reply to view.
>> No.8699586

>>8699576
>I don't know the answer but let me pretend I do
>>8699574
And columns are the best solution? Doesn't seem like much of a difference

>> No.8699592

>>8699586
Yes. Look at Halley VI.

>> No.8699598

>>8699048
I work in a bunker/datacenter disguised as a dentist office doing remote IT shit. Its kind of neat.

>> No.8699600

>>8699598
Why are data centers disguised?

>> No.8699629

>>8699600
For us its to impress potential clients that come on tours, but its also to hide the fact that we have like $30 million worth of servers and virtual hosts here.



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8699039 No.8699039 [Reply] [Original] [archived.moe]

if you gradually convert the neurons in your brain to digital information, at what point are you no longer you and you're just a copy of your former self?

that is, what specific quantity and arrangement of neural mapping is paramount to your own cognitive awareness? and if you can make a neural network with a digital interface that is gradually copying the neural maps in your head, how is this different from the plasticity which would overwrite your existing maps? can it not just be seen as a movement of mappings and not a destruction and copy?

I ask because i postulate that digitizing a person is a structural issue not a conscious-metaphysical one, however i can't tell whether or not you have just simply "moved" a person or you destroyed them.

Can you from a scientific model distinguish destroying someone and recreating them translated, planck unit by planck unit, in an arbitrary axis, from them simply moving?

1 replies omitted. Click Reply to view.
>> No.8699201

>>8699039
>movement of mappings and not a destruction and copy
Is there a difference? We happen to be organisms that, to an extent, understand themselves and that requires an idea of a "self" that is continuous and unique. But it's all the same to the world, a person that is copied with all memories and identical composition, with the original destroyed becomes the original for all purposes. To the new you, you are the same, and for the old you it doesn't matter (cause you don't exist).

>> No.8699212

You can't even prove that the 'you' that exists right now is the same as 'you' from five minutes ago.

>> No.8699219

No part of anything converted into something else is you. The same does not apply for all life, but human consciousness is really really picky in what's required to make it function.

>>8699212
It's the same consciousness. When the means to attain consciousness is permanently gone, so are you.

>> No.8699221

>>8699039
>>8699041
Is this at all based off the thread I posted on /lit/ a little bit ago?

>> No.8699575

>>8699219
Consciousness =/= soul



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8699024 No.8699024 [Reply] [Original] [archived.moe]

What do you think the cardinality of the continuum should be? What implications would this have on set theory and logic?

>> No.8699072

don't know much about set theory but i asked a professor about it. he said, ultimately, proving or disproving there is a cardinality between countable and uncountable, leads to one of two things: either there are things that are true which we cannot prove, or everything we have known is false in a sense and nothing matters.

>> No.8699728

>>8699072

Obviously I'm not talking about proving it one way or the other, at least from ZF(C). If we could prove it, then the axioms would be inconsistent.

I'm talking about other reasons to believe, not just "proving it". That is to say, what interesting things can we do by adding CH (or some form of its negation) as a new axiom?

>> No.8699773

>>8699024
I personally think when it comes to infinities you need to think differently. Maybe the continuum cannot be ordered with the aleph numbers. It's probably clear that I have no idea what I'm talking about



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8699021 No.8699021 [Reply] [Original] [archived.moe]

>"Mathematics was inven-"

>> No.8699064

People solve puzzles using insliratipn and creativity. Mathematics formalized this concept. Fuxking idiot its not either.

>> No.8699811

>>8699021
tative when came to solving problems.



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