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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
15270

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:

http://ebookee.org/index.php?tag=7

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.


14 posts and 2 images omitted. Click Reply to view.
>>
Solutions Manual to E&M, 3rd Edition by Purcell Anonymous 16/11/19(Sat)00:05 No. 16384 ID: 1ae570
16384

File 147951030462.jpg - (27.55KB , 406x500 , Purcell 3rd Edition.jpg )

Looking for the the solutions manual to Electricity and Magnetism, 3rd edition by Purcell and Morin. The problems are much more difficult and numerous than in the previous two editions, making it one of the best problem books on the subject. Was able to find the solutions to two analogous books in Classical Mechanics:

http://bookzz.org/book/2592413/e67f58

http://bookzz.org/book/2592412/fd6171

Sadly, all my searches for the solutions to the E&M book have been fruitless. It's the last manual that I need to complete my collection.




Anonymous 17/03/19(Sun)10:00 No. 16472 ID: 239da7 [Reply]
16472

File 148991401746.png - (112.72KB , 925x301 , Worldlines.png )

So, I have a question regarding physics and mathematics. Between the two, which would give me more "smart sounding shit." I don't mean learning it to brag, I mean stuff like pure mathematics sounding totally abstract to normal people. I just want to be in a different world basically. Kind of like induced autism? Or like a constant high but without drugs. Pic unrelated


1 post omitted. Click Reply to view.
>>
Anonymous 17/03/20(Mon)09:35 No. 16474 ID: 239da7

>>16473
Which topic is best for my reasons? Or do you just learn all of them when you take the courses for advanced mathematics?


>>
Anonymous 17/03/20(Mon)09:35 No. 16475 ID: 239da7

>>16473
Which topic is best for my reasons? Or do you just learn all of them when you take the courses for advanced mathematics?


>>
Anonymous 17/03/20(Mon)17:32 No. 16476 ID: 43d1ed

>>16475
Topology is definitely part of a standard mathematics curriculum for a bachelor or masters degree. Knot and category theory are more likely to be optional subjects or part of a Ph.D. course.

Topology is weird but somewhat intuitive. Knot theory is so abstract it's completely useless (AFAIK), so definitely useful for your purposes. Category theory sees some use in computer science, but since what it does (IINM) is generalize relationships between various mathematical objects, it requires some background in order to even understand what is being discussed.




Anonymous 17/01/16(Mon)06:55 No. 16414 ID: 57a468 [Reply]
16414

File 148454611224.jpg - (139.65KB , 630x916 , 5852d7ef120000c40beef7dd[1].jpg )

A mental health question for armchair psychiatrists.

Gender dysphoria is a mental health disorder as described in the DSM-5 as someone who identifies as something other than their assigned biological sex. Given that psychiatry still follows the scientific method as to making decisions over what is and isn't a mental disorder. There are still legitimate causes of such individuals.

My question is targeted toward those individuals who somehow manged to turn 'being transgender' into a trend. While they haven't done much to really affect the lives of others unless the lives of others are affected by whining and bitching about their lives on Tumblr without, as they say, checking their privileges. I want to know what a proper diagnosis would be for certain transtrending social justice warriors who encourage violence.

From what I read, gender dysphoria is a fairly weak disorder that most likely isn't the culprit of such extremism. So is it possible that schizophrenia or another such disorder may also be effecting said people? While I do believe a few of them may legitimately be transgender who only seek to find a voice and somehow end up falling into a bad group. There are still a majority of them that make me question their beliefs.

I probably should be asking these questions on a psychiatry forum instead of a chan website, but whatever, I anticipate some negativity.


19 posts omitted. Click Reply to view.
>>
Anonymous 17/02/01(Wed)06:53 No. 16445 ID: 57a468

>>16443
Noticed how I said it was only one factor. You appeared to have missed this part. Also, a society that doesn't change is due to extinction. One cannot keep things the way they are if life moves forward not backward. Why do you think there is so much controversy concerning Trump's administration?

This still doesn't change the fact you're ignoring the basis of science by saying shit like the DSM is unreliable or that there should be a better treatment without providing hard evidence to support such statements.


>>
Anonymous 17/02/01(Wed)08:29 No. 16446 ID: ef54e2

>>16445
>Noticed how I said it was only one factor. You appeared to have missed this part.
You only named one factor, so I only responded to one factor.

>Also, a society that doesn't change is due to extinction.
Society changes. There's no avoiding that. That doesn't mean it will change in a particular direction.

But, for the sake of argument let's suppose that in 100 years there is no progress of any kind in gender dysmorphia treatments and transgenders are universally accepted as being of the gender they purport to be, to the point that women have no dating preference between men and transsexual men, beyond reproductive capability. In other words, the situation is the same as today, only with total acceptance. Furthermore, this acceptance has caused transgender people to be statistically indistinguishable from the general population in pretty much all ways.

This hypothetical future doesn't change the fact that today the treatment is unsuccessful in many cases and that it's worthwhile to research new forms of treatment. If you disagree with this then I'm sorry, but the one who's resistant to change and progress is you.

>you're ignoring the basis of science by saying [...] that there should be a better treatment without providing hard evidence
I don't quite follow. I need to provide evidence for the statement "there should be a better treatment"? It's an opinion. Are you saying you do not believe I hold that opinion, or are you saying that you disagree with that opinion? Tough titty either way.


>>
Anonymous 17/03/18(Sat)22:31 No. 16471 ID: fc6638

>>16414
I'd say while there are a multitude of personal reasons SJW's take this shit to the levels that they do, the answer you are looking for could be simplistically boiled down to one word: ennui.

These people are to the core bored. It may arise from not being quite creative enough to make a purpose for themselves or they cannot fathom some way for them to be "interesting". Either way the way these people have seen themselves for years is as a uniform, pre fab part of modern america. No unique experiences, not enough creative wherewithal to express something unique and no unique "backstory" as some would say.

So, in lieu of any of this they instead experience ennui. In the grips of this ennui, there is no purpose to anything that you do, there is no reason you will be remembered, there is no way to be remarkable. S, in order to fulfill the need for these feelings they cling to a cultural trope that appeals to them: being persecuted. Being a part of a minority that is persecuted is a wet dream of these people, and the aspiration is to be remembered much like MLK. This gives them the "purpose" of fighting persecution, real and imagined. It gives them a sense of belonging and community with other like minded people. And finally, it gives them, in their mind, a path towards being remembered heroically.

long story short. the SJW is a product of the success of modern society with respect to achieving homogeneity and quality of life. They are also the product of that society lacking a clear sense of purposeful direction.




Logic is the 0-truncation of n-Category Theory. Americium 16/11/20(Sun)05:20 No. 16385 ID: ed8b6e [Reply]
16385

File 147961565686.png - (75.30KB , 500x562 , true_false_paradox.png )

Let's see you normies try to logic your way out of this one.


3 posts omitted. Click Reply to view.
>>
Americium 16/12/03(Sat)03:37 No. 16395 ID: ed8b6e

>>16388
?(x) := (x ∨ ¬x) : B→(B⊗B→B)

G(x) := ?([Im(G)=⊥]) : B→((B⊗B→B)→(B⊗B→B))

Using:
http://www.ivanociardelli.altervista.org/wp-content/uploads/2014/01/jpl-final.pdf

https://en.wikipedia.org/wiki/Iverson_bracket

https://en.wikipedia.org/wiki/Image_(mathematics)


>>
Anonymous 16/12/03(Sat)21:40 No. 16396 ID: b555dc
16396

File 148079761521.jpg - (181.56KB , 1330x748 , TB.jpg )

The answer to your question is F(ab)


>>
Anonymous 17/03/12(Sun)13:58 No. 16470 ID: fe855b

Yes




Anonymous 17/03/11(Sat)01:19 No. 16469 ID: 57133f [Reply]
16469

File 14891915467.gif - (17.29KB , 300x100 , 78.gif )

Alright /sci/, it's Goldbach proof time.

Who here can count to 112. All the way to that number. Congratulations. You are an abstract scientist.

The proof is that by itself and without other numbers the natural numbers do not exist.




Fast Oohplah 17/02/01(Wed)17:28 No. 16447 ID: 4318e8 [Reply]
16447

File 148596651718.png - (53.70KB , 506x200 , Audacity_Logo_With_Name.png )

Hey /sci/, how fast would an object need to travel in a circle to look like one solid ring or object. Like if a red ball span so fast it just looked like a solid red ring, not moving at all. How fast is that?

>pic unrelated


1 post omitted. Click Reply to view.
>>
Fogel Fry 17/02/01(Wed)23:23 No. 16449 ID: 6d05e5

Just for strictly non-serious reasons: How fast needs the red ball to travel to dupe the human eye and what would this do to the material the ball is made of?

Coming to that: What material needs the red ball to be made of?


>>
Anonymous 17/02/02(Thu)00:40 No. 16450 ID: 8b2816

>>16449
It depends on the sort of light that shines on the object. For example, strobe lights are used to visually inspect propellers as they spin in water. If you can time a light to shine very briefly at the same frequency as the object orbits, it will appear to be at a standstill in it regular, non-ring-like form.

Assuming a constant light source, such as the sun, and that the observer is not moving their eyes (because fast-moving objects are visible during saccadic motion), an orbit of a few centimeters in radius would appear as a solid ring rather easily. I would guess at less than 200 Hz (<12 kRPM). Roughly speaking, the larger the radius, the faster it must spin; more specifically, the tangential velocity must stay the same. Additionally, if the orbit is looked at from the side, the object will appear to move slower when it's on the far side of the orbit, so it will need to move even faster than if the orbit is looked at from the axis of rotation. The crucial factor here is how quickly the object traverses the field of view of the observer.


>>
Anonymous 17/03/07(Tue)20:01 No. 16468 ID: 68162d

Fuck idonno




PedoFinderGeneral pedospotter 16/08/17(Wed)09:10 No. 16351 ID: e75e2a [Reply]
16351

File 147141784023.jpg - (2.43KB , 135x90 , magic.jpg )

shouldn't all pedos go jail soon?

https://www.youtube.com/watch?v=DRkze_1MGo4

dont pedos ever wonder how come
other pedos know all about them
despite they all use winrar?

that its strange they break
eachothers security with
the most basic knowledge

do you think pedos will
ever realise its not really
scientifically accurate
Message too long. Click here to view the full text.


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Anonymous 17/01/25(Wed)19:31 No. 16436 ID: 3bc715

Never met a kiddy pickle tickler myself, but from what I can gather, some of them get caught due to extreme arrogance.
(i.e: "Those policemen won't get me, I USE A LIBRARY COMPUTER!")


>>
Anonymous 17/03/07(Tue)20:00 No. 16467 ID: 68162d

Yes




Anonymous 17/02/08(Wed)13:57 No. 16453 ID: eb6b3b [Reply]
16453

File 148655865765.png - (1.41MB , 1873x735 , pol disinfoagent1673875092y329.png )

The Vaccination of little Tommy Autistic.

When Tommy was a wee little lad at 4 years old, his mommy took him to a tax payer funded doctor's office to get a "booster shot." Little Tommy had no idea what a booster shot was, but he went in excitedly, mostly just because the waiting center had a little play area for him and other kids to play with blocks and such. It was then, when doctor told Tommy's mommy that it was time for Tommy to get his first booster shot! As Tommy sat down on the white papered bed, the doctor approached him with a big scary needle. OUCH! The needle pricked Tommy in the arm, and Tommy could not stop crying. The needle hurt Tommy, and Tommy had no idea why his mommy would let Tommy get hurt by this strange doctor. You see Tommy's mommy was a feminist in the 1960's who took part in the "revolution" for "female rights." She used to be what people would call, a "hippie," but after all her youth experimenting with various drugs, she decided to take her chruch's big business funded AA program's advice, and settle down and have a kid, in order to put her life back together. While she was in school, she "learned" that "vaccines eradicated disease" because they are "disabled" virus DNA that serve as target practice for the immune system's anti-bodies, so that way the immune system would be extra ready when a "live and active" version of the virus came around. She read in her government funded biology book how a Jewish doctor, Edward Jenner, "figured" this all out because his milk maidens, who were regularly exposed to cowpox, were relatively immune, so he created a concoction out of small pox pus, which contained the remnants of the disease, and inserted the pus into people's blood streams! It was all so sciency and believable to Tommy's mommy! After all, why would she be going to school if all this stuff was not true? Tommy's Mommy's also learned about diseases like polio and rhuebella, and tetanus, and measles oh my!


3 posts omitted. Click Reply to view.
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Anonymous 17/02/08(Wed)17:42 No. 16457 ID: 8b2816

Brain damage causes autism, now? That's news to me.


>>
Anonymous 17/02/11(Sat)04:43 No. 16458 ID: a97099

If you live in the USA and attended any school, you were vaccinated. Sorry to burst your bubble, but if your parents said you weren't, they're lying. They don't let un-vaccinated kids attend schools, public or private. That's simple fact.

So you can go ahead and kill yourself because you're a walking contradiction.


>>
Anonymous 17/03/07(Tue)19:53 No. 16466 ID: 68162d

Chut up




Anonymous 17/01/30(Mon)01:55 No. 16444 ID: b46211 [Reply]
16444

File 148573774380.jpg - (7.25KB , 300x168 , images.jpg )

Hello there /sci/. I have a challenge for you. Take your favorite futuristic or otherwise out of reach tech from any movie (let's say a light saber) and try to explain if humans can replicate it with a few modifications.


>>
Anonymous 17/03/05(Sun)03:26 No. 16465 ID: 9c4b9c

lightsabers contain crystals.
http://starwars.wikia.com/wiki/Lightsaber/Legends




Anonymous 17/02/26(Sun)19:45 No. 16463 ID: ff4681 [Reply]
16463

File 14881347566.jpg - (53.95KB , 374x339 , BAA09_16_brain_bio-chip.jpg )

so, I know you guys use word filters, or at least have a times, I have some questions about them, now, this being said, I'm aware that your guys' word filter isn't exactly used in the same way that this kind is... at least in spirit, or cause behind the technicalities

out of curiousity, does anyone know of any studies on manipulation of perception in a pervasive way involving mediums of communication and what is said or isn't said?
does anyone have any knowledge of studies involving methods of control that are linguistics oriented or say... are designed to pick up on related contexts and the like with various signifiers?

some stuff's popped up lately and I'm *extremely* interested in this, I might have to learn a fair bit of technical jargon and concepts but I feel like it's probably worth it

on the one hand it seems like the attempts to engage in this are laughable but at the same time I know that sometimes these sorts of things can get real good real fast, especially when there's already a load of collected data that's not purposefully spoiled to challenge the attempt at deriving context to start silencing apparently said things


>>
Anonymous 17/02/27(Mon)02:10 No. 16464 ID: ef54e2

What?




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