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/sci/ - Science & Math


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10411425 No.10411425 [Reply] [Original] [archived.moe]

hello fellow physics terabrains. if you haven't heard, a new textbook on quantum field theory was recently published, and what makes it notable is that it's based off the QFT course lectures given by the late, great Sidney Coleman at Harvard. and of course we all know that Sidney is a true physicist's physicist, one of the all time greats of QFT.

https://www.worldscientific.com/worldscibooks/10.1142/9371

has anybody gotten a chance to look at the book? i'm considering picking it up



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10411411 No.10411411 [Reply] [Original] [archived.moe]

Please STEMfags, help a brainlet out. What's the image formed when light comes out from two divergent lenses?



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10411409 No.10411409 [Reply] [Original] [archived.moe]

Alright /sci/entists, I've been reading all kinds of articles and it seems that genetic research/modification is going to have a massive take-off in the somewhat-near future.
I'm looking to see your predictions. I predict that:
>genetically modified pets will become more and more popular (not just hypoallergenic, but "designer" pets and super-speciallized show animals)
>genetic vaccines will almost entirely replace regular ones, and the anti-vaxxer community won't be able to complain because there are no "dangerous metals" or anything involved but a particle of tungsten or gold and genetic material
>genetic modification will allow for "designer babies" that are smarter/stronger
>genetic modification for grown adults will be more available than vaccines, with "purchasable genes" allowing for enhancement of all kinds
I'm not saying we'll all have super-powers, but just think of the (commericial) possibilities!
pic related, obvious stretch



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10411397 No.10411397 [Reply] [Original] [archived.moe]

What concentration would you choose /sci/? Help me decide, I’m leaning towards robotics but not sure. I’m minoring in bioengineering

>> No.10411399
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10411399

>>10411397



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10411378 No.10411378 [Reply] [Original] [archived.moe]

Hey guys, I'm trying to do homework and study for Pre-Calculus but my teacher doesn't teach and there are no examples like the problems I'm supposed to do in either of my textbooks or resources I can find online. Does anyone know how to do any of these problems?

>> No.10411384

>>10411378
here's a tip:

|x-4| = x-4 only for x≥4

>> No.10411387

>>10411378
>there are no examples like the problems I'm supposed to do

Good. You should be solving problems based on understanding and not copying the steps from the examples.

>> No.10411394 [DELETED] 

>Floyd, Robert W., “Assigning meanings to programs,” Proceedings of Symposia in Applied Mathematics, Vol. 19 (1967), pages 19–32.
http://www.eecs.berkeley.edu/~necula/Papers/FloydMeaning.pdf

>Hoare, C. A. R., “An axiomatic basis for computer programming,” Communications of the ACM, Vol. 12, No. 10 (1969), pages 576–583.
https://www.cs.cmu.edu/~crary/819-f09/Hoare69.pdf

>Hoare, C. A. R., “Proof of a Program: FIND,” Communications of the ACM, Vol. 14 (Jan. 1971), Pages 39-45.
https://www.cs.cmu.edu/~crary/819-f09/Hoare71.pdf

>Keshav's How to Read a Paper
http://ccr.sigcomm.org/online/files/p83-keshavA.pdf

>Error Detecting and Error Correcting Codes by R. W. Hamming
http://www.lee.eng.uerj.br/~gil/redesII/hamming.pdf

>A Case for Redundant Arrays of Inexpensive Disks (RAID) by David A. Patterson, Garth Gibson, Randy H. Katz
http://www.eecs.berkeley.edu/Pubs/TechRpts/1987/CSD-87-391.pdf

>The Mathematical Theory of Communication by Claude Shannon
http://worrydream.com/refs/Shannon%20-%20A%20Mathematical%20Theory%20of%20Communication.pdf

>Communication Theory of Secrecy Systems by Claude Shannon
http://netlab.cs.ucla.edu/wiki/files/shannon1949.pdf

>The UNIX Time-Sharing System by Dennis M. Ritchie and Ken Thompson
http://people.eecs.berkeley.edu/~brewer/cs262/unix.pdf

>A Fast File System for UNIX by Marshall Kirk Mckusick, William N. Joy, Samuel J. Leffler, Robert S. Fabry
http://people.eecs.berkeley.edu/~brewer/cs262/FFS.pdf

>The Emperor's Old Clothes by C.A.R. Hoare
http://zoo.cs.yale.edu/classes/cs422/2014/bib/hoare81emperor.pdf

>On Computable Numbers, with an Application to the Entscheidungsproblem by Alan Turing
http://classes.soe.ucsc.edu/cmps210/Winter11/Papers/turing-1936.pdf

>On the Computational Complexity of Algorithms by Hartmanis and Stearns
http://fi.ort.edu.uy/innovaportal/file/20124/1/60-hartmanis_stearns_complexity_of_algorithms.pdf

>> No.10411429

>>10411378
>>>/wsr/



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10411375 No.10411375 [Reply] [Original] [archived.moe]

>Universities should be punished for giving black students lower grades

https://www.google.com/amp/s/amp.theguardian.com/education/2019/feb/20/universities-should-be-punished-for-giving-black-students-lower-grades

Should black students be given affirmative action grades to finish college?

4 replies omitted. Click Reply to view.
>> No.10411391

A society that prioritizes and caters to its most useless, non-productive members is by definition doomed to be counterproductive, dysgenic, and regressive. This will work itself out, one way or another.

>> No.10411396

>>10411375
>The government has recently announced that it plans to improve how black, Asian and minority ethnic (BAME) students perform
>black, Asian and minority ethnic
>Asian
say good by to British academia, anglos. Asians will soon overrun oxbridge

>> No.10411402

>>10411396
Nah, these aren't East Asians. These are Indians and Pakistanis

>> No.10411408

>>10411385
Kek but don't you think that's a bit racist for the people who believe that we are all equal??

>> No.10411416

>>10411385
They do here in Canada.
It isn't rational, it's biased and racist unless there's also one specifically for non-minorities.



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10411359 No.10411359 [Reply] [Original] [archived.moe]

Why are rational number superior compare to "real" number system? Have you ever even seen irrational numbers, imho they do not even exist. The completeness axiom is human made bs.
"If a non-empty set A has an upper bound, it has a least upper bound. "

Oh cmon, its like saying that if humans are earthbound then God exists.


Discuss.

8 replies omitted. Click Reply to view.
>> No.10411400

>>10411395
Rationals are well defined. "Reals" are constructed by literally saying "also irrationals exists besides rationals".

>> No.10411403

>>10411400
>"Reals" are constructed by literally saying "also irrationals exists besides rationals".
Well, that's just factually wrong. Have you ever heard of Cauchy sequences or Dedekind cuts? Have you seen any construction of the reals before? They don't start by saying "irrationals exist".

>> No.10411406

>>10411359
>Have you ever even seen irrational numbers, imho they do not even exist
Math doesn't care if it exists physically or not.

>> No.10411419

>>10411403
Cauchy sequances and Dedekind cuts are just fancy way to say it.

>>10411406
How come?

>> No.10411430

>>10411419
>Cauchy sequances and Dedekind cuts are just fancy way to say it.
So, what you're saying is, constructions of the reals that are well-defined in terms of rationals are bullshit because a consequence of the definitions is that irrationals exist. In other words, you again take as a premise that irrationals don't exist and use that to prove irrationals don't exist.



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10411346 No.10411346 [Reply] [Original] [archived.moe]

How long untill people get to go to space just to have sex in zero-g?



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10411337 No.10411337 [Reply] [Original] [archived.moe]

i'm not getting a lot of responses on /g/ so i'm posting here

what are the biggest problems with AI? I don't understand AI or machine learning. How are the boundaries of AI determined?

>> No.10411345
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10411345

https://www.unz.com/akarlin/superintelligence-competition/
https://www.unz.com/akarlin/transhumanist-techs/

>> No.10411347

>>10411337
>How are the boundaries of AI determined?
What do you mean by "boundaries"?

>> No.10411349

>>10411347
what dictates the limit of a machine's knowledge? how do they process and store endless information?

>> No.10411350

Failure to understand the problems being solved, and hardware.

>> No.10411360

>>10411337
the term AI is thrown around a lot, and what it actually refers to in the modern parlance is pretty poorly defined. like for example Google makes a neural network that can identify porno pictures and screen them from google image searches, and they call it "AI", but whatever, who cares that you have porn pattern recognition. not AI. or IBM has "watson" go on Jeopardy and beats Ken Jennings because it has wikipedia downloaded to its hard drive and a really good search algorithm "hurr durr this is AI" but not really.

the best definition i know of with respect to AI is the turing test, or generalizations of the turing test. a turing test is basically have a person have a text-message conversation with the AI, but without telling them it's an AI and not a real person, and then let them have a discussion -- if the person doesn't realize that the thing they're talking to is not a real person, then the AI passes the turing test and it is some sort of legitimate "artificial intelligence". now keep going with that -- require the AI to do more things that pass as human, like make sounds and music and art and equations and new theories of physics and run for president and start tweeting about fake news and shit, then you've got a real AI.



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10411305 No.10411305 [Reply] [Original] [archived.moe]

>psychology and psychiatry is not real science
Do you agree with that notion?

4 replies omitted. Click Reply to view.
>> No.10411362

>>10411330
>every decade the last decade's set of standards are tossed out as bunk and replaced with some new norm
This. And they get incredibly mad when you mention it to them.

>> No.10411367

>>10411305
yes, psychology is made up trash for women to pretend they understand things

>> No.10411368

>>10411305
>psychology
>psychiatry
post picture of a psychoanalyst

>> No.10411372

>>10411330
The studies are done with scientific method in mind, but the inability to replicate them after a decade or so shows how humans drastically change with the current ideology.

>> No.10411401

>science is a well defined category
Anyway

>psychiatry
Yes, it's just primitive as fuck

>psychology
You could call it a social science I guess, it's as much of a science as anthropology or linguistics

>psychoanalysis
No, it's astrology tier pseudoscience and even a self-aware scam in some cases



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10411275 No.10411275 [Reply] [Original] [archived.moe]

Will consumer electronics actually get a lithium ion successor in the next 10 years?

Lithium Sulfur maybe or something?

Battery life in modern electronics is too fucking shit.

Posted here instead of /g/ because I don't wanna discuss GPUs, Thinkpads, or Programming Socks.

>> No.10411317

>>10411275
https://www.youtube.com/watch?v=OY2C_SshyeQ



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10411271 No.10411271 [Reply] [Original] [archived.moe]

Where do you study?

10 replies omitted. Click Reply to view.
>> No.10411319

>>10411313
are there no quiet study rooms?

>> No.10411325

>>10411313
>Try to study when mid-terms are approaching
>Once quiet library becomes normie central
>Black people probably studying sociology do nothing but eat at their desks and play with their phones
>Girls studying nursing are chatting about retarded shit
>Probably like half of the people are actually studying
Just fuck my shit up

>> No.10411328

>>10411319
this is at Boston University, the shithole of shitholes

>> No.10411333

>>10411328
ah

>> No.10411351

>>10411325
>Black people blasting rap music through headphones
>People using study rooms to go on twitter and daydream
>45 year old woman talking to her daughter on the phone
>Mexicans
>Dumb Chad walking 17 laps around the library because he can't find any females to stare at
>People eating fucking chips
Library is no longer a place for study.



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10411228 No.10411228 [Reply] [Original] [archived.moe]

You have 3 cars, two cars cars are identical and interchangeable. You have 5 driveways. You can only park one car per driveway and call cars must be parked. How many different permutations can you have? Please explain how you solve this.

>> No.10411248

>>10411228
60 permutations.
The first car has 5 possible options, any of the 5 driveways.
The second car has 4 possible options, once the first car is parked.
The third car, which is identical to the second, has 3 possible options once the second car is parked.

5*4*3=60

Really I don't think it matters that two of the cars are identical, but someone smarter than I am will probably correct me.

>> No.10411255

>>10411248
for the identical case you have to just say
the second and third cars can be stuck into any of the four remaining driveways, so you have the options of remaining driveways 12, 23, 34, 13, 24, and 14, i.e. six ways to stick two identical cars in four driveways, so it's 5*6=30

it's half because there are double as many ways for the last two cars if they are distinguishable (as in your solution) -- you'd e.g. be allowed 12 and 21 instead of just 21 so it doubles all the ones i listed



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10411184 No.10411184 [Reply] [Original] [archived.moe]

My area of study? Why, neuroscience of course.

>> No.10411188
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10411188

>>10411184
kek, brainlet detected

>> No.10411193

>>10411188
what a disgusting kike

>> No.10411203

>>10411193
>t. butthurt he can't into string theory

>> No.10411205

>>10411193
Damn you are right, >>10411188 what a disgusting kek



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10411131 No.10411131 [Reply] [Original] [archived.moe]

Is there some way I can preserve myself long enough to when Stein's Gate/Days of Future Past-style time travel will be possible?

>> No.10411151

>>10411131
You're already preserved by virtue of ever having existed.
You need to figure out how to convince the time-travelers of the future to come get you.

>> No.10411152

>>10411131
Yes, literally freeze yourself and wait.

>> No.10411180

>>10411131
>Is there some way I can preserve myself long enough to when Stein's Gate/Days of Future Past-style time travel will be possible?
What have you tried?

>> No.10411323

>>10411131
Steins Gate is the actual reason i havent killed myself, and its made me view life as something infinitely meaningful.

>> No.10411353

>>10411323
I love steins;gate.
Only anime I've ever really held so close to my heart



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10411128 No.10411128 [Reply] [Original] [archived.moe]

Today I will remind them of MIT/CFS/SPARC, Kitty Hawk of Fusion.

>Group of professors and students at MIT design a plus-gain fusion tokamac in their spare time.
>Using High Temperature Superconductors (HTS), the main compression magnets do not require -200 degree coolant to work, and at higher magnetic field strength. Also cheaper and smaller then conventional superconductors.
>Additive-manufactured Inconel blanket contains liquid Lithium, both as a coolant and as a breeder for Tritium (makes its own fuel on site, without outside nuclear fission reactors).
>HTS can bend and fold, allowing the reactor to come apart without destruction for repairs and upkeep (unfolds like a flower, pull out blanket, put in fresh one).
>Original design for Advanced Robust Compact (ARC) reactor showed it could easily give 100x energy gain, but plans are now to build Soon-as-Possible (SPARC) demo unit, small enough to fit in a college lab but still produce 10x gain in single shots
>Already has full funding from the US gov, as well as Bil Gates, even Italian energy giant Eni added $50m.

Demo compression rings to be tested 2019, SPARC online by 2030, ARC plants by 2050. Combine with Thermal Transfer (Malta), Dry Electrode/UltraCap (Tesla), and Solid State batteries, we will have the power to teraform the entire planet a thousand times over. Space colonization and cylender swarms a centery to follow. GGEZ.

http://www.psfc.mit.edu/sparc
https://en.wikipedia.org/wiki/ARC_fusion_reactor
https://www.youtube.com/watch?v=efOlmF3wjJE
https://www.youtube.com/watch?v=KkpqA8yG9T4
https://www.youtube.com/watch?v=L0KuAx1COEk

4 replies omitted. Click Reply to view.
>> No.10411171

>tfw have the ability to make a net gain fusion reactor that could fit in a car
>tfw health problems and couldn't finish grad school
You're all thinking about this the wrong way. Magnetic containment vessels are the worst thing that ever happened to fusion.

>> No.10411207
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10411207

>>10411157
Iter was designed with the "smallest magnets available" at the time. "We will build the reactor around that size restraint". That restraint being fuckoffanddie massive.

20 years later, we have magnets that are cheaper, smaller, more powerful with lower temperature superconductivity, with other bonus properties (flexibility exc). "This is no longer a physics problem, this is an ENGINEERING problem. Here is our 'wing'".

>"Hey you know we have the math here saying this will work well withing spec"
>"Oh we got the funding we need to build demo loops and produce educational lectures/talks/podcasts/presentations/demonstrations, thanks!"

nevergonnawork.jpg has hurt itself in its confusion.

>> No.10411219

>>10411207
the fact that you wrote "lower temperature superconductivity" makes it clear you probably know jack shit. anyhow, the successor to ITER, DEMO, is already in planning phases and probably will use the newest magnets (that are available when they publish their TDR). and ITER is going to provide tons of good data and experience on how to make DEMO work

there is always a problem in big science of "what will the technology be in 10 years? should we delay the project based on that?" so that's life. ITER, DEMO, etc. needed to go ahead because you can't wait forever gambling on unknown unknowns. on the other hand, SPARC will never happen, just like so many other fantasy fusion ideas

>> No.10411240
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10411240

PS i also don't approve of OP's pic of luftwaffe nuking Queens. bunch of nazis on here today but i thought SPARC anon wasn't that dumb -- guess i was wrong

>> No.10411392
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10411392

>>10411240
I could not find my cute/lewd earth-chans



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10411109 No.10411109 [Reply] [Original] [archived.moe]

What does /sci/ think of Doctor Jill Bolte Taylor? Is she just a liar? At what point do we trust someone because of their credentials?
>Harvard trained Neuroanatomist
>spent 10 years+ studying
>she was president of NAMI (the National Alliance on Mental Illness) for a decade
>she was studying strokes and their effects when she had a massive one in 1996
>it shut down the whole left side of her brain
>this had major effects
>one of which was realization she had gained psychic abilities
>prediction, pre-cognition and the ability to feel a persons intent
>this lasted for some time during her recovery
>it took her 8 years to recover
>she continued her study
This is her TED talk, it was the first ever TED talk to go viral apparently: https://www.youtube.com/watch?v=UyyjU8fzEYU

>> No.10411129
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10411129

>TED talk

>> No.10411135
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10411135

>>10411129

>> No.10411143

>2 replies no substance
So /sci/ and /pol/ are obviously the same.

>>10411129
I'm literally Jewish senpai. You can read her book which is a best seller and has been translated into 30 different languages. But you have to buy it so I can't link it faggot.

>>10411135
First time on /sci/ in months. Maybe get out more.

>> No.10411164

>Bolte Taylor began to study about severe mental illnesses because she wanted to understand what makes the brain function the way it does and the cause between her dreams becoming reality while her brother cannot connect his dreams to reality, making them a delusion

Going by these first few lines from wikipedia, she sounds like a kook before she even had her stroke.



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10411103 No.10411103 [Reply] [Original] [archived.moe]

Most profound and effective way to strengthen one's logical mindset?

Is problem-solving based approach to learning logic truly the most effectual?

>> No.10411121

>>10411103

Just play around with it in the same way a kid plays with blocks.
Once it becomes child's play, all following steps will be obvious.

>> No.10411132

>>10411103
stare at this and tell me why it is true
[math]\left(A\implies B\land\lnot B\right)\implies\lnot A[/math]

>> No.10411214

>>10411121
this

and years
let your brain get used to it

>> No.10411279

Write true expressions as Haskell types, find inhabitants for them, use them to find other inhabited types, then reflect.



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10411101 No.10411101 [Reply] [Original] [archived.moe]

Need a solution. Atleast a jumpstart if not a solution. Thank you.

>> No.10411149

proove that altitudes are medians



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10411083 No.10411083 [Reply] [Original] [archived.moe]

A child could see this is wrong, yet it is taught in every university freshman course in the USA. Why is physics such bullshit?

11 replies omitted. Click Reply to view.
>> No.10411310

>>10411083
How did the helicopter reach that hight..? It's almost as if it applied work in order to get up there

>> No.10411321

>>10411083
this image doesn't know if the work is being done by the helicopter or the ground
by earth:
>gravity * 0 movement = 0
>gravity * height = work
>gravity * height = work
by helicopter:
>thrust * 0 movement = 0
>thrust * negative height = negative work
>0 thrust * negative height = 0

>> No.10411331

>>10411083
you're confusing mechanics of objects in a gravitational field with other forms of energy

>> No.10411339

>>10411083
nice painting nigga

>> No.10411417

>>10411301
"Should?" Says who?



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