Archived threads in /sci/ - Science & Math - 1035. page

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>>8570565
I've never encountered a "book" made of a sequence of articles by different authors like that, which I liked.
And especially if it's about branes, you need not feel bad for being lost as each author will assume a different background. And the supersymmetry signs will always be wrong.

>>8570564
Why is that? Apart from my never being happy with the treatment of more philosophical aspects of GR, like the equivalence principle, I think Wald is a good read.

On that topic: I'm interested in the expression of the derivative of a vector in curvelinear coordinates. That is...
In Euclidean space, if

[math] {\bf x} (t) = \sum_{ i=1 }^n x^i(t) {\bf e}_i (t) [/math]

you have

[math] \dfrac {\partial } {\partial t} {\bf x} (t) = \sum_{i=1}^n \left( \left ( \dfrac {\partial } {\partial t} x^i (t) \right){ \bf e}_i (t) + x^i (t) \dfrac {\partial } {\partial t} {\bf e}_i (t) \right) [/math]

And I'm looking for that general expression (and in fact the second derivative too) for a setting where the inner product is a general Riemannian metric g, with all em Christoffels and whatnot. Is it maybe even in that book?

>>8570564
>p-adic teichmuller uniformization of complex riemann surfces
>for dummies

That phrase really only applies to people who are able to eke out a living.

Obviously, poverty is not fun, and no one is saying it is.

women are attracted to perceived power and social status

>born with an IQ of 90
IQ doesn't work that way, it's an approximation of g at best

how much g is determined by genetics and how much is determined by environment is still entirely contentious. Even if 80% of g is heredity, that's still a range of 80-120 IQ purely from the "nurture" side of things

>but more than half the people on the show will lose
That's not true, the probability of winning is 50%. Either you win or you don't.

>>8569378
>Four options
>One is right
>33.34%
>4

>>8569378
Easy, just become a macropolymath and learn everything.

Extreme Autism.

Oh boy here we go again

>>8567641
because he has an IQ over 200 and is smarter than john von neumann

also he writes them on the windows of every building he enters so he doesnt forget, its a form of OCD

>>8567489
>monks having superhuman qualities
what are you, gay?

>>8567489
You know when you were a kid the doctor would tell you to breathe in and out at a nice pace, to look away from the needle and to relax your muscles when piercing your flesh?

Remember how when you actually followed his advice it hurt a little less, almost nothing, compared to when you would cry and move around and breathe like a fucking bitch. Right? Member?

Well, they just do that but after training it for decades and becoming masters of ignoring pain.

Seriously, whenever you see these monks show off it is always some pain resistance bullshit. You never see them shoot fireballs or levitate buildings. Just resisting some guy hitting them with a stick. Big fucking deal. It is just training to ignore pain.

>>8567523
What about super strength? Is it just technical stuff?

>This watermelon is your brain... if it was a watermelon.

>>8562471
>>starting your sentences with "Let..." outside of a math textbook
patrician way of phrasing desu

i do this sometimes without even meaning to
it's like mathematics and academia have become a reflex response
somebody will say something, and i'll automatically make some vague mathematical connection, and then i just zone out and think about the baire category theorem until somebody slaps me

i can't help it please don't stab me

Is it possible to get post-baccalaureate research experience in mathematics?

I participated in research my freshman, and sophomore years. I was diagnosed with a brain tumor my junior year. Afterwards, I never got back into research because I was just trying to get my degree, and get back to a decent state of health again.

Now, I want to apply to graduate school, but
1. My grades post-tumor diagnosis are mediocre as fuck. 3.1 GPA I think. Probably 3.5-3.6 from before it.
2. I haven't been involved in research for 3 years, and I want to go into a field unrelated to that research.

This should probably go in /adv/, but they're basically no help.

I just e-mailed a prof. at a large university local to me, and the plan is basically to ask him to take me on as a research assistant either with, or without pay, gain some relevant experience, and then re-evaluate what my options are.

not my fault this autist doesn't know how to define a function

>>8556977
Kek'd. I gave you a perfectly suitable example back in my OP >>8554916

The technical term for it is called circlejerk.

>>8570732
>>>reddit

>>8570726
Name 1 study where this happens.

>>8569644
I think you're overcomplicating it, you have two equations:

[eqn]\dot{x}=f(t)-x(t)[/eqn]
and [eqn]\dot{y}=-y(t)[/eqn]

The second one is easily solvable as $y=e^{-t}$ which means you only have to worry about the first one

>>8569715
But neither of those are necessarily true you neglect an arbitrary real g that scales the velocity vector based on time, or rather you are assuming that it is always equal to 1.

>>8569726
Well, yes I took it to be 1 because if it's constant the magnitude doesn't really matter and I sort of assumed it is based on the wording of the problem, I could be wrong though.

>>8569583
I think the most he has is undeserved co-authored papers.

Yes, he is an actual scientist. Astrophysicist. Researcher at the University of Maryland, Princeton, and became director of the Hayden Planetarium. Lead author on a number of papers.

I believe he's retired from active research but is likely still a reviewer and advisor.

>>8569583
He gets a lot of hate because of his cringy twitter posts but if you meet him in person you'll see he's a cool guy who really does love physics

It's understandable that people hate him because of his egregious fame, especially when there are physicists out there doing much more strenuous research. However, he gets people interested in science and that's something we can all appreciate.

>>8569299
I like it, now present us with math.

>>8569364
>>8569364

So far all I can present to you is that since the Eddington-Finkelstein is based upon the tortoise coordinates it cannot remove the singularity in the field because the equation is 2GM + 2GM ln|0| in which all terms are singularities.

>>8569373

Thus, the EF is a bad coordinate system and I suggest the Einstein-Rosen Transformation where u2 = r - 2m. The singularity at 2GM is replaced by u=0. Time vanishes at the event horizon which is expected, given that null geodesics have closed to a light like surface.

I feel you OP.

>>8569221
What are you, gay?

>>8569207
Read books on applied math or books that introduce particular subjects to non-mathematicians (those with titles like "Topology for Economists").
Of course this assumes that you have knowledge of other fields besides math, and that you're learning math because you think it'll have eventual uses in some field.
(If you're one of those people who think you're "doing math for its own sake", your field is really computer science.)

>>8569207
Read a book on proofs.

That's what autists do.

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When you're smart but lazy, mathematics is the one and only way to get by in the real world.

>>8569193
You cheeky shitposter.

Math is complex. The complexity can encourage you or not. If it encourages you, then you may like it.

How much of a brainlet you have to be to not understand this?

>>8568868

Ask a professor doing research on it.

I played deus ex human revolution and mankind divided. Im basically an expert on implants and the ethic of bio engineer.
Do you have any questions?

university physics
stewart calculus

wtf how can that nigga see he's just a circle

wtf he's talking too

just visiting /sci/ from /pol/ damn yall got some messed ups shit

yeah, it's called gravity

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