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Oh, hey. We're actually having old posts pruned now.

File: 1445572916272-0.jpg (59.59 KB, 600x338, 300:169, StellaratorLead1280x720.jpg)

File: 1445572916649-1.jpg (390.63 KB, 672x1310, 336:655, StellaratorGraphic672.jpg)

 No.3293[Reply]

now this looks like shit straight out of a sci-fi novel

 No.3299

Does it work?


 No.3300


 No.3852

File: 1457711792941.jpg (132.47 KB, 700x531, 700:531, w7x_emf.jpg)

agreed


 No.3853

File: 1457712981136.gif (108.41 KB, 540x200, 27:10, tspacexform.gif)

>>3300

woah dude




 No.3839[Reply]

Hey anons, I've seen before an approach to evaluate an infinite sum of an infinite series applying algebraic number theory, any thing to read talking about such applications?

 No.3848

bump




File: 1455691683234.jpg (2.18 MB, 2797x2797, 1:1, Mixed_onions[1].jpg)

 No.3816[Reply]

Onions irritate the eye by emitting stuff that combines with the water in eyes to make acid.

Is it possible to use onions to "farm" this acid for latter use? Does this acid have any practical use (even if better acids exist for these purposes)?

1 post omitted. Click reply to view.

 No.3819

>>3817

Easier with access to modern industry, or easier period?


 No.3821

File: 1455807018102.jpg (37.94 KB, 509x380, 509:380, 1455707096304.jpg)

>>3819

It's obviously easier to create sulfuric acid from elemental sulfur than it is to extract microamounts of it from onions.


 No.3825

Sulfuric acid is so easy to make we actually make sulfur fertilizers from the acid, rather than naturally occuring Sulfate salts. Look up the contact process, and the lead chamber process before that. Sulfuric acid is the Swiss army knife of chemical industry. Look up some bulk prices, you'll be shocked how cheap this shit is.


 No.3842

>>3816

>lets waste onions for trace amounts of sulfuric acids

this is by far the most retarded idea i have ever heard, by anyone. im speechless.


 No.3847

>>3842

nah it's not really retarded, just inexplicably ignorant




File: 1452387818866.jpg (76.9 KB, 740x610, 74:61, USS_PT-109_on_board_SS_Jos….jpg)

 No.3726[Reply]

Hey /sci/, I like sticking together old and new technology. I was wondering if you could tell me how I could arm an 80 foot Elco Torpedo Boat in the future. I was thinking light artillery railguns and supercavitating torpedoes. The power for the railguns would be generated using graphene, either in the form of a skin on the hull of the boat or some sort of gill system. Also, the guns could either be aimed manually or would be controlled by a computer for accurate, long-distance shooting. If you were to use an Elco 80 foot Torpedo Boat for smuggling, is there any way to give it a decent armament whilst remaining realistic?

 No.3843

File: 1456810343795.jpg (10.43 KB, 300x271, 300:271, Agent 006.jpg)

Didn't we tell you already that was a bad idea when you wanted to do this with a Balao? You'll never get more energy out of the graphene moving through the water than it takes to push the ship through the water. Better to just use a conventional engine.

As for the smuggling, you're best bet is going to be a sub with electric engines. If they run on batteries then you're going to have a surface or run shallow and snorkel every day or couple of days to charge the batteries and swap air. Additionally the hull will ring like a bell on active sonar unless it has some sound absorbing skin. This won't completely eliminate the sound of the sub but if you're running ducted turbines on electric motors the squirty water sound combined with the soft skin may mimic the sound and return signature of a biologic (a whale) and fool a green sonar operator. You'd need to operate the ducted turbines in pulses and match the frequency of the pulses to the tail strokes of something like a blue whale but it could be possible.

The big problem with a soft skin is that it will want to cave in at the front and this will cause additional drag and slow the sub significantly so to move at speed while submerged you'll want to be able to push some hard plates out or fill bladders with pressurized sea water to brace the skin. This will largely negate any sound deadening characteristics of the skin but give you a boost in speed.

The other big problem with soft skin is that it will limit the dive depth. Go too deep and the hull-skin will cave in and tear open. This happens on steel and titanium hulled subs today and if you've ever been in a sub approaching its rated crush depth you might have seen the inner hull bow in visibly.

For armament skip the railguns and just use torpedoes. Early subs were armed with guns because torpedoes were expensive, unreliable, inaccurate, and difficult to aim and fire. That's no longer the case and there are now a variety of long ranged guided and unguided torpedoes with anything from no warhead to nukes and they can run slow and silent or scream through the water at over 200 knots.

If you want long distance fire cruise and ballistic mPost too long. Click here to view the full text.




File: 1456225709004.jpg (967.81 KB, 1260x1260, 1:1, Structure of the Sun.jpg)

 No.3831[Reply]

Hello /sci/entists, I have a question of dire matter. If everyone on Earth could eat the sun, how long would it take?

 No.3832

File: 1456227166982.gif (908.12 KB, 250x250, 1:1, 1454254763001.gif)

Okay /sci/ bros, I've done a little bit of research and this is what I've found out:

Global Population: 7.4 Billion

Lifetime Consumption of Food: 35000 KG

Global Average Life Expectancy: 68.5 years

Mass of Sun: 1.989 × 10^30 KG (1,989,900,000,000,000,000,000,000,000,000,000,000)

Where do I go from here?


 No.3833

>>3832

Multiple food by population

Divide sun by result

Realize you just wasted, at the least, 12 fucking hours waiting to be told how to do basic math.


 No.3838

There is no time component yet, which is what OP wants to know.

Get some kind of average on how long it takes a person to eat some unit of food per unit of time. Grams per second or whatever. Multiply rate by amount of humans on Earth. Divide mass of sun in same mass unit by that rate for all humans. Get time for humans to eat the sun.




File: 1456421588391.jpeg (150.25 KB, 1440x810, 16:9, image.jpeg)

 No.3834[Reply]

Do you trust sugar, gmo food, and margarine?

https://en.m.wikipedia.org/wiki/Miraculin

I personally want to get a hold of this African berry and experiment with sugar subsitutes. If you chew on it then sour foods taste incredibly sweet for up to an hour. Some people chew on them and eat pickles and lemons, you could use it to switch to eating various healthy but sour foods, and it would be useful for anyone going through chemo therapy. The Japanese government doesn't have the same hang ups we do with food additives and the distilled form was first found by a Japanese scientist, so maybe I could get it there.



File: 1454296951068.jpg (27.3 KB, 480x640, 3:4, 1533836_1103915622964829_4….jpg)

 No.3783[Reply]

With the prodigious advancements in computing technology, I can't help but wonder; why bother leaning mathematics when a computer can calculate large, complicated numbers in record speed?

Wouldn't it make sense to focus on subjects computers are incapable of comprehending and leave the maths to machines?

 No.3785

Because that's not what high-level math is about.


 No.3798

Someone needs to tell the machine what to do first


 No.3823

>>3783

Because you undestand neither math nor comp-sci.

>complicated numbers

U wot m8? The only "complicated" number is a lone zero.


 No.3829

>>3783

High level math isn't just about computing large complicated numbers, there's a fuckton of abstract shit that computers can never precisely calculate and so they just estimate. Even if it was all stuff that a machine could do perfectly, you would still need someone who understands the subject first to tell the machine how to do it.




File: 1455995374645.jpg (42.34 KB, 400x426, 200:213, 1369424906771.jpg)

 No.3826[Reply]

This guy is going to be using someone else's dick. If he jerks off is that gay?

http://www.counselheal.com/articles/22040/20160220/injured-soldier-to-get-first-penis-transplant-in-u-s-history.htm

 No.3828

>>3826

I guess no because the guy whose dick he's getting won't be present in the act.




File: 1456021649379.jpg (27.88 KB, 608x342, 16:9, 34387af093a5b70db0409d353f….jpg)

 No.3827[Reply]



File: 1454525371486.jpg (18.11 KB, 640x480, 4:3, cold_dead_eyes.jpg)

 No.3792[Reply]

Since observation changes the state of a particle, then could the act of observation be quantified as a force? If so, what is the unit measurement for observation?

2 posts omitted. Click reply to view.

 No.3811

>>3803

What about the inviolability of the Uncertainty principle? i mean, i get that we can't measure/observe particles, but why is it wrong to theoreticaly assume that they have a certain position and speed?


 No.3818

>>3811

It's a direct mathematical consequence of how physical variables work in quantum mechanics.

In quantum mechanics, a physical variable is an operator on the wavefunction. Position operator is multiplication by coordinate, and momentum operator is derivative by coordinate (multiplied by -iħ). The two operators are Fourier transforms of each other; that is, you can formulate the momentum operator in an alternative way by performing the Fourier transform on the wavefunction, so you describe the particle not by its probability distribution in space but in wavenumber, which makes the momentum operator a simple multiplication by wavenumber. (Fourier transformation turns derivatives into multiplicators and vice versa)

If you assume a particle has a certain position, then you can describe it by Dirac delta function — a "function" whose value is zero almost everywhere, except in the point where the particle is, normalized so that the integral of such "function" is one (so you can imagine as if the value of the function in that one point is infinite). A Fourier transform of Dirac delta function is a function of form e^ikx (the constant k is not relevant here), and you probably know that this is a cosine wave in real and sine wave in imaginary component, and that it's absolute value is equal to one everywhere. So, if the position of a wavefunction is completely certain, then the wavefunction must be a Dirac delta function in space coordinates, but this means the momentum of that particle is completely undefined, as the absolute value of the wavefunction in wavenumber coordinates is a constant — every wavenumber is equally possible.

The Uncertainty principle is what you get if you assume that the wavefunction is a Gaussian distribution. Fourier transform of a Gaussian distribution is another Gaussian distribution, whose width is inversely proportional to that of the original one. So, the product of widths of the wavefunction in space coordinates and in wavenumber coordinates, both Gaussian distributions, must be a constant. There's also another mathematical proof that you cannot construct a function for which the product of standard deviations iPost too long. Click here to view the full text.


 No.3820

>>3793

I don't see any reason why a classical force can't be represented as an operator either.


 No.3822

>>3820

One could, yes. But it's not useful in any regards, as potentials prove to be more fundamental than forces.


 No.3824

>>3818

That comment made me realise how much of an ignorant fuck i am, but i sort of understand, my question now being, if it's all math then how do we know it applies to the real world? couldn't we found some other way of doing it that would allow us assume in theory the speed and position at the same time?




File: 1452409729622.jpg (2.66 MB, 3264x2448, 4:3, 20151224_001734.jpg)

 No.3727[Reply]

Those who take STEM degrees under the misguided notion that it'll do them any good except self-sealing themselves back into their mothers' basements but now $50,000 in debt and eight years wasted.

2 posts and 1 image reply omitted. Click reply to view.

 No.3730

Agreed with OP.

You'll get much better career options by going to a trade school.

Trade School:

* Affordable

* 2 years to graduate

* Students and teachers are professional and considerate

* Everything you learn is useful and applicable

* Concepts learned are state of the art

* Can immediately start a good job right after graduating

* Job market has a high demand for skilled tradesmen

College:

* Soul-crushingly expensive

* 4+ years to graduate

* Student body are morons, teachers are curry/rice nigger graduate students that don't know how to speak English

* Have to waste months on useless leftist mind control classes where all you do is write BS papers and agree with the teachers' political views

* Everything you learn is 7+ years out of date at the time that you learn it

* After graduating, have to take minimum wage entry level jobs and/or unpaid internships for 2+ years before you can get a good job

* Via the H1B program (which Obongo recently expanded in the omnibus bill last month) you have to compete with hundreds of millions of curry/rice niggers who lie about their credentials and are willing to work for peanuts


 No.3732

>$50,000 in debt

>he doesn't have full scholarships and stipends to pay for it

Goddammit fix your site hotwheels


 No.3766

>>3730

Non-US University:

* Paid by taxes which everyone with a job does shoulder.

* Exchange and long-time students do not get their tuition paid through taxes so they aren't fed through their time spent doing less than others (between 430 and 1700 $ a year).

* Stipends cover half or more of all living expenses, study aid paying if income of parents is not too high already.

* 3 years as an undergraduate after which employment is already possible, 5 years total.

* Morons are cut out of the student body by effectively failing everything of importance in the first year.

* Students are caucasian and speak proper English while a third of them went abroad and/or learned a third language, exchange students know proper English and the course language even if it is not English, professors are caucasian and did reaseach and teaching in US-colleges, also were in other countries like Britain or China for research.

* STEM means to write two thesis papers and not a single paper more to finish graduation because it is not an lib arts degree. Some papers end up published internationally and become actually relevant.

* STEM means that only a small amount of credits (less than 6 %) can be earned outside the field, but also by internship programs.

* Professors give lectures about their current research.

* Professors reference current research papers when they are deemed relevant to the topic at hand.

* Professors don't know you as graduates, don't have the time to discuss politics, and more often than not do not care about your presence in Uni, or what you do outside of it because why should they.

* After graduation, be part of a (paid) research group for up to a few years, with or without becoming a doctor, pay for a fresh graduate starts at 4300 $ gross.

Other quaternary education institutions:

* Tuition can vary between none (usual) and something above 1000 dollars a year.

* Post too long. Click here to view the full text.


 No.3813

File: 1455554030054.png (416.22 KB, 805x779, 805:779, accept.png)

>>3727

>using a samsung note 2 a day before christmas to take a picture of a store and an antenna


 No.3815

>>3727

>>3813

>not scrubbing metadata

the 4chan hacker collective known as gentoomen are known to roam for wild metadata




YouTube embed. Click thumbnail to play.

 No.3812[Reply]

Time for rage.



File: 1455362348152.png (123.22 KB, 870x689, 870:689, 1451722127452-2.png)

 No.3810[Reply]

Hi, /sci/, I'm just cross posting this since I think you'd enjoy it.

>>>/lit/8601

Pic unrelated



File: 1447372425948.jpg (110.43 KB, 263x400, 263:400, Superman_Heat_Vision[1].jpg)

 No.3446[Reply]

The explanation for Superman's heat vision has always been that it was concentrated and focused x-ray vision.

Ignoring how X-rays don't work even remotely like Superman's sight, would it even be physically possible to focus intense x-rays to the point they can melt steel?

2 posts omitted. Click reply to view.

 No.3780

>>3446

Also, it wouldn't be nearly as localized as you'd think.

Most things are relatively transparent to x-rays. Take concrete, for instance. Depending on wavelength, the "penetration depth" (the depth at which half the x-rays are absorbed ) is 4-60mm (or higher, but then you've moved up into gamma rays). For comparison, take the penetration depth to be 1cm for simplicity. Now look at a light bulb. Now move twice as far away from it and look at it again. That change in light intensity is the equivalent of a 2cm chunk of concrete for x-rays.

You try to, say, weld an I-beam and a significant chunk of the x-rays would just go right through into whatever is behind it.

Not to mention the amount of x-ray scattering that would happen.


 No.3804

>>3446

are you asking if x-rays can melt steel beams?


 No.3807

"Testing stuff"


 No.3808

:^)


 No.3809

>:(




File: 1444385087043.png (458.17 KB, 1239x1640, 1239:1640, paranoid anons tech guide.png)

 No.3167[Reply]

https://8ch.net/g/res/3537.html

all best intentions. peace.

 No.3365

>>3167

I have seen that linked either here or on halfchan once. Not meaning to contradict its relevance in general, but how is this relevant to doing science on a computer specifically?


 No.3796

>>3167

/g/ is leaking


 No.3806

Why would anyone dl a plugin to disable another plugin when you can just disable flash?




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