Archived threads in /sci/ - Science & Math - 129. page
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oh look, a list of math buzzwords
>>8091347
engineer here
at number theory
>>8091347
>P=NP
>Genius level gap
![4102xbZaTDL._SY300_[1].jpg](https://i.imgur.com/coOB8lh.jpg "4102xbZaTDL._SY300_[1].jpg")
If information about nuclear fission is available in any physics textbook, why can't any country with enough money build a nuke and why are "nuclear secrets" so secret?
>>8091222
Its technical and engineering data that is kept secret. The science is available to everyone
>>8091222
because engineering something is harder than sciencing it.
>>8091222
We know about the designs that were used, not about the process to manufacture a core.
How do I become a 'Mad Scientist'?
>>8091036
study stem and have a short temper
Make shit in your garage
Burn down the garage with the shit you made
There we go.
>>8091036
Fail your STEM degree
Say :fuck it, i dont need 'em
Try to invent shit to become rich with internet guides
->80% nothing happens/you get bored and hungry cause no job
->10% something explodes cause no work guidelines
->10% you make something useful, a giant corp notices and they buy you off cause you need money to eat something
Such hard is life
God tier telescopes. I'll start. The Celestron 21064 AstroMaster 90 EQ Refractor Telescope is God.
I have Bresser 70/900. Cool telescope, but it comes with some god awful eyepieces. I'm planing on buying gso or synta 10" dob.
PS: anyone know what mount is it?
Better picture of the mount
>>8090959
What is the best cheap refractor telescope for someone that's never owned a telescope?
Hypothetically speaking, let's assume you had some kind of g-diffuser, that completely disengaged the pull of gravity around a perimeter. Let's say you had a spaceship.
Since there's no longer any drag on you, wouldn't you be able to accrue speed until you reached lightspeed and time-traveled without any further quibbling with the laws of physics?
My logic is assuming that since space is a vaccuum, that there won't be anything to slow the thrust of your ship once it's started moving thanks to Newton's third law.
Wait, does this g-diffuser negate the effect of outside gravity on all objects within the effected area. Or does it negate all gravity in the effected area including gravity caused by objects within the area?
OP here, I mean Newton's First Law.
I was just baiting.
>>8090685
Outside gravity working against the localizied area.
Is being a highschool teacher a joke? Or is a a good job? I've always liked the idea teaching. Do u also need to have a high GPA?
>>8090133
>Is being a highschool teacher a joke?
depends
>Or is a a good job?
no
Do u also need to have a high GPA?
no
Teaching to a bunch of idiots who fucking hate school and teachers and are only there because they are forced to sounds like hell. Nobody respects high school teachers, I sure didn't when I was a teenager brat.
>>8090133
Depends on the school.
I would love to be an AP science and math teacher at a top private school where the average SAT score is above 2000.
I would hate having to teach remedial arithmetic to inner city niglets.
What's the worst /sci/ film or other media you've ever seen?
Currently watching this absolute dogshit.
>>8090113
I never understood the hate directed towards evolution (at least scientifically), especially considering films like The Core, 2012, and iOrigins exist. I understand that a certain amount of will suspension needs to take place, but both of those were obnoxioulsly bad. I suppose it's the same with Lucy, everyone jumped on the "hurr using 10% of ur brain is myth", as if science fiction was meant to be an accurate reflection of reality.
>>8090150
2012 is infinitely more believable that Evolution
Just reached the bit where the idiot sings in the shopping mall an supports the dragon
![4a82015a07fe2a2f5a912b6116860a38[1].png](https://i.imgur.com/IAEefJ3.png "4a82015a07fe2a2f5a912b6116860a38[1].png")
1/2 = 0.5
1/0.0002 = 5000
1/0.00000000002 = 50000000000
etc
It's obvious what's happening here; as the divisor becomes smaller and approaches zero, the answer grows larger and approaches infinity. Why isn't the answer to x/0 defined as infinity and the answer to 0/0 defined as zero?
nice bait
Try approaching from the other side of 0 and you'll get -infinity. Also try taking calc 1, that should clear this up.
>>8089770
When the numerator becomes small and approaches zero and the denominator does the same, the division can be anything, depending on how fast the numerator goes to zero relative to the denominator. It could be 0 or 7 or infinity or not converge.
What's the number N(n) of directed circle graphs with n verties (a,b,c,d,...) and edges (f,g,h,...)?
For the first two, it's simple to check the number is two:
N(2) = 2
1) Either, say
f : a -> b
g : b -> a
2) or, say
f : a -> b
g : a -> b
N(3)=2
1) The graph where all arrows go in one direction, say
h : c -> a
f : a -> b
g : b -> c
2) The graph where one of the arrows point in another direction, say
h : c -> a
f : a -> b
g : c -> b
so that both f and g point...
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Bump
>>8089392
Isn't an equalizer already the special case of a pullback when the two arrows have the same source?
On that note, I have a somewhat stupid question (probably too obscure for /sqt/ though):
According to
https://qchu.wordpress.com/2012/09/29/monomorphisms-and-epimorphisms/
the natural map (m: d --> e in OP's example) is stated to always be a monomorphism, meaning that the pullback is a subobject of the product. Intuitively I can see why, but I can't seem to formally prove it from the...
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>>8091282
d is not the product here
this is what I know:
when 1 exists,
-the product of 2 objects is the pullback of their unique arrow towards 1
-given two arrows f, g, with same domain, codomain, the equalizer [f, 1_f] and [g, 1_f=1_g] is the pullback of f by g
-if the pullback of two arrows f, g exists, then if f is monic, then g*(f) is monic
this is false when you replace monic by epic
the kernel pair of an arrow f is the pullback of f by itself
-if the kernel pair of f exists,...
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How hard is it to get into a grad school for statistics if my undergrad grades are mediocre
I don't know about stats, but I majored in math and my undergrad advisor literally told me I wasn't good enough to go a good grad school. I had all A's and B's (except for a bio class) and did a decent course load including grad level classes in measure theory and algebraic topology.
>>8087366
god damnit
>>8087359
Why would any grad school want to accept you? Have you done anything encouraging aside from grades? I don't know what you expected to happen.
The CEO-Emperor of Mars Elon Musk has conscripted you employee-citizen of Mars to design a probe for exploring the oceans of Uranus.
What's that employee? Uranus does not have an ocean? Stupid employee! Don't you know that Uranus has a layer of liquid hydrogen and liquid ices starting at around 7,500 km deep?
His Muskiness wants a probe that can operate at temperatures exceeding 3000 K and pressures in 0.1 Megabar range. The probe must be able to take pictures and transmit back science for a month. Funds are almost unlimited, but probe must mass less...
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>>8074855
>>8074858
you might find the following phase diagrams useful employee
>>8074855
Uranus has already been explored by several Big Black Crafts, my liege.
NASA is building a new Space Shuttle
http://observer.com/2016/02/nasas-new-space-shuttle-is-a-work-of-futuristic-art/
https://en.wikipedia.org/wiki/Dream_Chaser
SpaceX BTFO
>>8099787
k, keep us posted
>>8099787
Didn't realize NASA stood for Sierra Nevada Corp
>>8100873
salty spacex faggot detected
Chess thread.
Recommended reading
>My System - Nimzowitsch
>Endgame manual - Dvoretsky
>Zurich 1953 - Bronstein
1900 Elo here. I'll post some problems of various difficulty.
White to move and win.
Black to move and win.
Not really useful, but still interesting.
Doesn't Schrodingers cat make it plausible that some humans are walking around with their own wave functions uncollapsed? So some day you could look at one of those humans, and thus collapse his wavefunction and there will be a 50% probability that he dies. Maybe even you are one of them. Maybe some day a stare can kill you. Scary.
>>8106249
wat?
Your post collapsed my function
>>8106249
Yes, this is exactly what Schrödinger was talking about
The other one is over the bump limit
Anyone knows the answers to these?
I know the answer would differ depending on the program, amount of students in said program, etc., but is it common to not be given any type of assistantship during the first year of a Master's degree?
>>8097066
I would guess A for both, but I really have no clue.
>>8097066
Use snell's Law. The index of refraction of vacuum is less than the index of refraction of air, so that means the angle in vacuum has to be larger than the the angle in air.
Now look at pic related. The red lines are the rays of light, and the blue lines represent the surface between air and vacuum and the lines normal to the surface. Snell's law applies to the angle between the light ray and line normal to the surface.
For question 7 (box labelled 8 in the picture) notice the angle the light makes...
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