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/sci/ - Science, Technology, Engineering, and Mathematics

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New Textbook/Book Request Thread deadbabies ## Mod ## 13/08/25(Sun)06:03 No. 15270 ID: f34135 [Reply] Stickied

File 137740339172.jpg - (401.45KB , 1680x1050 , titanfalsecolor.jpg )

First off, hello there, I'm deadbabies, and I will be taking over as /sci/ moderator. Rules will remain the same. Please use the report function if you see posts that violate the rules, but also do not abuse it.

I have officially expanded the scope of /sci/ a bit. You may discuss Science, Technology, Engineering, and Mathematics here now. No science is discriminated against as long as it's of the peer-reviewed variety. If someone wants to discuss Anthropology or Social Science, by all means, let them. If you do not like it, just don't post in the thread.

The IRC channel #/sci/ is now (finally) re-registered and I am running as operator on here. Feel free to stop by and say hi. I do leave my computer idling on IRC, so check back or leave me a message if you have any ideas, suggestions, or just want to tell me off. You can get onto #/sci/ by joining the server irc.7chan.org at port 6667. You can also use SSL at port 6697 but you will have to set your client to accept invalid certificates.

ADDITIONALLY and IMPORTANTLY I have had several requests on IRC regarding the old Ebook FTP that we used to have. Unfortunately, the mod who ran it entered the military and no longer runs or maintains it. I have no plans to make another one, but if one of you guys would like to, by all means advertise here.

That being said, I'm just going to leave this link here:


You may find what you seek here.

I will be unstickying the old ebook/source articles thread. Please post any new ebooks/source articles here, and feel free to post any working links from the old thread there; I will eventually be deleting it.
Message too long. Click here to view the full text.

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Anonymous 14/10/28(Tue)20:22 No. 15954 ID: ab4c09


Lies! Server is down until autumn. Have a nice vacations.

America VS the metric system Anonymous 11/11/28(Mon)22:57 No. 12847 ID: 2dcfee [Reply] [First 100 posts] [Last 50 posts]

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It’s hard to find comedy gold like this, however this is priceless


Apparently a true American tries to show the failures of this evil satanic scientific metric system and fails horribly.

Best parts:

1) Arguing that centimeters are not part of the metric system!
>"Centimeters, while in common usage, are NOT officially recognized metric units"

2) Actually trying to measure something using 0.1 mm obviously not understanding that this precision is not actually possible with human hands.
>"In metric notation this would be 1219.2mm by 2438.4mm."

123 posts and 10 images omitted. Click Reply to view.
Anonymous 14/02/12(Wed)03:58 No. 15537 ID: 44326e

This attitude is why we're still stuck in the past.

Anonymous 14/03/14(Fri)04:09 No. 15592 ID: 1615b6

this attitude cost mankind one satellite. good job.

Anonymous 14/03/16(Sun)07:12 No. 15596 ID: b6dcec

And this attitude is why he won't be working with a great many people in his own country.

Enjoy your exciting job in retail, OP.

Anonymous 14/07/25(Fri)22:51 No. 15766 ID: 86e709 [Reply]

Youtube - Toggle Video
  Everything I've read about Eugenics has been about how it's pseudoscience. Ok. but, by the sound of it, it was just a selective breeding program. If artificial selection works in every other species, and natural/artificial selection has produced us, ...where's the problem exactly? I have yet to see how a sophisticated selective breeding program couldn't produce a better human body or brain or both. It's what we do every time we pick a mate who we think will make us some primo offspring.

pic semi-related: Just try listening to this without clawing your eyeballs out (why are so many people so fucking retarded and how can we replace them with upgraded models?)

4 posts omitted. Click Reply to view.
Anonymous 14/10/27(Mon)03:27 No. 15949 ID: ef4f14

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Natural selection is all about people deciding for themselves who they reproduce with. This prevents unattractive people from reproducing. This makes it very hard for fat American women with entitlement complex to breed, eventually they will be extinct.

Eugenics is all about some arbitrary group of people deciding who you are are are not allowed to breed with. Ideally, this could be used to breed unfit people out of the gene pool a lot faster, but who are these people that decide who is unfit?

Right now, the people most likely to implement a eugenics program in the western world, are the SJWs that want fat American women with entitlement complexes to breed like rabbits, and everyone who questions the socil order, to be castrated. There is no such thing as a eugenics program that does not fundamentally violate someones basic human rights.

Anonymous 14/10/28(Tue)20:35 No. 15955 ID: ab4c09


I'm the anon who wrote >>15925 this and, as a side note, I ONLY listen to electronic music. I forgot to respond to that part of your post when I wrote my answer. Although I don't listen to Mark Sherry (I'm not a fan of tech trance for the most part) I like melodic progressive house and trance. Like Benz and MD and Digital Witchcraft to name a couple of good groups. I also like deep house sometimes and occasionally a smattering of drum and bass and psychedelic trance (or goa trance, whatever you want to call it).

Anonymous 14/10/31(Fri)19:26 No. 15956 ID: 2f260d

>Natural selection is all about people deciding for themselves who they reproduce with. This prevents unattractive people from reproducing.

Theoretically, yes. However, society has become a larger influence on breeding than any sort of biologic mechanism as fitness or attractiveness. A person with high wealth or social status can have as many children as their bodies can put out if they want to. In practice, it's the stupid people who are breeding most, where they are then taken care of by the goodness of society. Capitalism results in a world of vapid pretty boys/girls with no physical or mental strength whatsoever who suck on the corporate tit all day. Communism results in a world of ugly, dirty folks with strong arms and three brain cells to their name who work themselves to death. Either way, they are ruled by inbred fools who were born in the throne and honestly believe that success is just who you ARE, not something to be attained.

Pick your favorite kind of Hell. It is not possible for anything to fix it.

Anonymous 14/09/20(Sat)07:30 No. 15881 ID: ea642d [Reply]

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should i get a mac book pro or a window for computer science?

24 posts and 2 images omitted. Click Reply to view.
Nattajerk 14/10/20(Mon)22:39 No. 15943 ID: e55706

also apparently prestanda is a swedish word for the amount of useful work accomplished by a system.

det är underbart

Anonymous 14/10/27(Mon)03:16 No. 15948 ID: ef4f14

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Literally anything is better than apple. But, if you use mirco$oft, you are a pleb. Build your own Linux distro from scratch like a real man.

Anonymous 14/10/28(Tue)15:14 No. 15953 ID: b2989d

why are you even considering apple

Anonymous 14/10/27(Mon)22:39 No. 15950 ID: d126e2 [Reply]

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What are the factual negative and positive side effects from watching pornography? I recently did some reading into this and found a lot of articles talking about how the neurons create stronger pathways to the brain from the pleasure reward that comes from watching pornography (much similar to the effects from taking drugs). This can lead to addiction and dependency on this type of stimulus to become aroused. So I come to you /sci, does pornography have a negative effect on the brain?

PlutoniumBoss!Y1SVQJ54eA 14/10/28(Tue)08:42 No. 15951 ID: 465a65

Almost any stimulus can potentially become linked to a dopamine response and become addicting, really. And too much constant dopamine wears down your receptors. So yes, overindulgence in pornography can do this, but so can overindulgence in television, video games, or anything else.

Anonymous 14/10/28(Tue)12:51 No. 15952 ID: 4321f6

It's commonly known that pornography can be addicting, but besides from the addictive side of it does it come with other negative side effects on a neurological level?

Anonymous 14/10/19(Sun)11:15 No. 15940 ID: e9758b [Reply]

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How much money you reckon ebola raised for in the name of science? thanks little fella!

Anonymous 14/10/19(Sun)11:33 No. 15941 ID: be3d41

Thank the dead.

Anonymous 14/10/20(Mon)23:08 No. 15944 ID: bac648

hey, it's not like we thank the dead sand people we kill for oil... credit where credit is due

Anonymous 14/10/27(Mon)03:12 No. 15947 ID: ef4f14

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I know a company in Chicago that manufactures medical equipment, suddenly found itself with a massive backlog, starts hiring literally anyone with machining experience, right off the street. I've been not unemployed for two weeks now thanks to our little buddies.

Anonymous 14/10/12(Sun)19:00 No. 15929 ID: b20a90 [Reply]

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Hello /sci/!

Does anyone please know of a program that can analyze torrents? What I want it to do is to create a printout of all the files in the torrent. I also want to make comparisions of torrents; to see if two torrents have files with the same name and/or the same hash value.

Anonymous 14/10/16(Thu)11:00 No. 15936 ID: 789203

Yes, dumptorrent.

Hashes are computed per-block, not per-file. Meaning, the hashes a torrent contains will depend not just on its particular contents, but also the particular order in which they appear, and the block size that was used. It's very unlikely that two distinct torrents containing the same file will also share any hashes, even if the block sizes are the same. It's even less likely if the file in question is smaller than twice the block size.

Let n be the absolute offset of the file on the torrent A (given by the sum of all the file sizes that came before), and let m be the same on B, if file_size >= block_size * 2 and n is congruent to m modulo block_size, then there will be at least one duplicate hash between the two torrents. For randomly constructed torrents (a reasonable situation) with a random file_size the probability of the congruency condition being met is of 1/block_size. So for block_size = 4 MiB (a common block size), the probability is lower than four million to 1.

Anonymous 14/10/07(Tue)08:26 No. 15918 ID: 1b02b6 [Reply]

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2 questions. In photo,

Exhibit 1: A point charge q exerts its electric field over a spherical body. Along the flux lines diverging "radially" away from point charge, there exists 2 points at opposite ends of sphere's surface area (along diameter). The electric field, E, in accordance with Coulomb's law, is stronger towards the charge than away from it, the vector lengths of E indicating this ever dying weakness, and vectors, dA, normal to the area.

Told: That the total electric field on the body is zero, because the cross product of the electric field on both points are "equal" but opposite, cancelling each other out. This applies to all points along surface area of the sphere.

Question: What is wrong in my photo? It seems that they have completely forgotten about Coulomb's law, in that the closer you are to a body, the stronger the electric field. If the point charge was negative, I imagine the electric field vectors to be a lot larger along the sphere's hemisphere closest to the point charge, and smaller on the other hemisphere. Wouldn't all but the tiny difference between the electric field strengths remain after cancellation? Shouldn't the total electric field be in slight favour of the negative charge's force?


Exhibit 2: a. A point, p, inside charged sphere has an electric field, E, of zero.
b. A point, p, exists in the sphere of a charged similar body comprising a sphere with an attached appendage that loops around half the sphere, with same electric field as E in exhibit 2a.

Told: That in all closed surfaces, the net electric field, E, at any point in the closed system is zero.

Message too long. Click here to view the full text.

Anonymous 14/10/07(Tue)09:10 No. 15921 ID: 1b02b6

Also, why are the charges along the surface? Is it just easier to think that way after summing all the negligible point charges together?

Anonymous 14/10/10(Fri)03:15 No. 15926 ID: 789203

1. I don't see how the field strengths on the surface could possibly have opposite directions unless the point charge is inside the sphere.

2. I agree with you, it seems counter-intuitive. I could easily construct a closed fractal shape that has infinite surface area on one side of the charge and is nearly spherical on the other. I'm not in physics, so I don't know what to tell you. See if this link helps:

Anonymous 14/10/10(Fri)19:00 No. 15928 ID: 1b02b6

I worded it poorly. E isn't opposite on both ends, dA is (normal to the surface on opposite ends). I was just trying to say that the field dies off the farther you are away from charge.

Nokia Cutter 14/09/30(Tue)10:08 No. 15900 ID: 91d0e5 [Reply]

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Is it even possible to get an old Nokia phone on a modern service provider ? I realized that I never use my iPhone for calling so it would just be better to get an iPod and a different phone. What do you guys think ?

Anonymous 14/10/07(Tue)03:51 No. 15916 ID: 1d75bc

If you mean using an old Nokia on a modern providers network?
Then YES. Plenty of networks still run 2G (GSM/GPRS/EDGE) channels for backwards compatibility and emergency dispatch services until 2016 (US) and 2017 (UK). Though reception can be patchy.

If you mean getting an old Nokia on a new service plan... oh wow.... seriously?

Realistically you're best off holding off a couple of months for the Nokia 3310 - Pureview as it hold to it's namesake for quality but with 3G which'll keep it going into 2030.

Anonymous 14/09/18(Thu)21:20 No. 15877 ID: 6cf8dc [Reply]

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I got drunk last night and got to thinking... what is stopping lightning from striking houses and tv antennas outside and shit when houses today aren't made with lightning rods?

Matchbox Prince 14/09/20(Sat)07:57 No. 15883 ID: 2f260d

1) Houses don't generally have large TV antennas anymore.

2) Houses are generally surrounded by taller structures like streetlights and trees.

Nattajerk 14/10/01(Wed)23:36 No. 15904 ID: ee6591

this ancient device you know as a tv antenna is connected to ground, and provides a clear path for electricity to follow. radio towers are frequently struck for example, the idea is not to avoid lightning but to divert it.

so, in essense, nothing is stopping lightning from striking your house. it is rare, of course. trees, taller buildings, etc will take the most risk of being struck, but having your property struck is certifiably rare by comparison.

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