Anonymous at Mon, 29 Jul 2024 12:24:47 UTC No. 16301721

Can someone explain what's going on here? How do these dirac deltas go from being multiplied to being summed? And what's the meaning of a difac delta with an argument squared?

Anonymous at Mon, 29 Jul 2024 12:25:44 UTC No. 16301723

What's a good book that actually tells you how to perform GR calculations? The few I've read are all pure theory, none of them teach you how to calculate a metric given a particular mass configuration.

Anonymous at Mon, 29 Jul 2024 12:41:47 UTC No. 16301738

>>16301721
They have used a standard dirac delta identity which is non-trivial to prove:

https://en.wikipedia.org/wiki/Dirac_delta_function#Composition_with_a_function

Also there is a typo in that final line, it should be +R in one of the terms.

Anonymous at Mon, 29 Jul 2024 13:17:51 UTC No. 16301771

>>16301738
thanks you are right

Anonymous at Mon, 29 Jul 2024 20:35:05 UTC No. 16302380

>>16301714
Can someone help me with this?:
> 1). In a magnetic spectrometer with a magnetic field strength of B = 1T, a particle’s path has a curvature with a r = 3m radius perpendicular to the magnetic field lines. Additionally, a flight time of t = 17ns over a distance of s = 2.2m is measured. Assuming the particle has an elementary charge q = e, find the particle's mass.

I've solved 1), using p = qBr = 899.38 MeV/c then v = distance/time etc.

But what confuses me, is special relativity. Why can I just do v = distance/time here? But I still used p = γmv to get the mass. Idk, it just confuses me, or did I make a mistake?

Is the velocity the same in the frame of reference of the particle for classical and relativistic problems?

(Would also be nice if one of you anons could share their result, I have no one to compare with.)

Anonymous at Mon, 29 Jul 2024 21:08:06 UTC No. 16302430

>>16302380
> Why can I just do v = distance/time here?
Because it's all calculated from your frame of reference as the observer. Though in the normal spectormetry equation I don't believe special relativity is used at all even when calculating the mass.

Anonymous at Mon, 29 Jul 2024 21:08:16 UTC No. 16302432

>>16302380
Classically the force is mv^2/r = p^2/mr where p = mv. Relativistically, the force is also p^2/mr, but now p = \gamma*mv.

Velocity is defined as distance/time - this never changes. Conservation of momentum in relativity is applicable to the relativistic momentum, not the classical one.

Anonymous at Mon, 29 Jul 2024 21:23:32 UTC No. 16302457

what is happening in my brain when I can't do simple arithmetic? everything else is seemingly normal(language, reasoning, motorics) but when it comes to math my mind goes blank.

Anonymous at Mon, 29 Jul 2024 21:53:23 UTC No. 16302482

>>16302430
>>16302432
Thanks anons, didn't take relativity yet and have to pass nuclear/particle physics. Hope I'll do well, I "know" the equations/some of the theory, but applying it is gonna be fucked kek. I'll work some problems and learn.

Thanks again.

Anonymous at Tue, 30 Jul 2024 01:36:43 UTC No. 16302669

Why is the function f(x) = x^x so weird. What causes the graph to randomly go both up and down in in the interval 0 < x < 1?

Anonymous at Tue, 30 Jul 2024 01:51:55 UTC No. 16302687

>>16302669
[math]\frac{d}{dx} x^x = x^{x}(\ln{x}+1)[/math]
the minimum of [math]x^x[/math] is at [math]x=\frac{1}{e}[/math]
before this point, [math]\ln{x}+1<0[/math] and so the overall derivative is negative, so it decreases
after that point, [math]\ln{x}+1>0[/math] and so the derivative is positive and the function is increasing

🗑️ Anonymous at Tue, 30 Jul 2024 01:53:11 UTC No. 16302688

>>16302669
What else would you expect the graph to be? The limit of both interval endpoints will be 1. In the interval itself, any x raised to a power < 1 will be less than x.

Anonymous at Tue, 30 Jul 2024 03:07:11 UTC No. 16302770

>>16301723
im pretty sure theres only like 2 known solutions to the GR equations, you could just look them up.

Anonymous at Tue, 30 Jul 2024 09:18:59 UTC No. 16302990

Let f be any function such that f(x+1) - f(x) ∞ as x ∞. Does f(x)/x ∞ as x ∞? I'd appreciate any help, I'm utterly stuck on this exercise

Anonymous at Tue, 30 Jul 2024 09:25:51 UTC No. 16302995

>>16302990
Formatting came out crappy, here's what I meant: Let f be any function such that f(x+1) - f(x) --> ∞ as x --> ∞. Does f(x)/x --> ∞ as x --> ∞?

Anonymous at Tue, 30 Jul 2024 09:28:24 UTC No. 16302996

Trust me you are the perfect catalyst of this stupidity. I don't exactly switch to the enemy, I follow your signs. You're dead and neglecting me. It's a two way problem. Keep confident now, we will win, and if we don't we will get out of hell quick. Simple.

Anonymous at Tue, 30 Jul 2024 10:03:24 UTC No. 16303026

>>16302995
No, consider a function like

[eqn]f(x) = x^2 + \log(1 + \lfloor x \rfloor - x)[/eqn]
then
[eqn]f(x+1)-f(x) = 2x + 1 \to \infty[/eqn]
but the limit
[eqn] \lim_{x \to \infty}\frac{f(x)}{x} [/eqn]
doesn't exist.

Anonymous at Tue, 30 Jul 2024 10:24:30 UTC No. 16303039

>>16303026
That's brilliant, thank you

Anonymous at Tue, 30 Jul 2024 12:54:38 UTC No. 16303185

>Sylvester's law of inertia
Why is it called that? Does it have any applications in physics? Specifically for rigid body motion or where does the name come from?

Anonymous at Tue, 30 Jul 2024 20:13:54 UTC No. 16303635

does anyone know how this effect is called?
is like the double slit experiment, but with an impenetrable obstacle in the middle. my professor argued that depending on what was inside of the obstacle, the phase interference of the electrons would vary and the resulting detection would be different, even though the wave can't enter the obstacle, because the wave function probed the entire space.
my professor explained something like this in class years ago but it doesn't appear in my notes and I don't know how to look it up on google

Anonymous at Tue, 30 Jul 2024 20:16:12 UTC No. 16303638

Integral over a surface A, but with d^3x? Would you say this is a typo and they meant d^2x?

Anonymous at Tue, 30 Jul 2024 20:17:26 UTC No. 16303645

Fagpots

Anonymous at Tue, 30 Jul 2024 20:26:22 UTC No. 16303664

>>16303635
Never mind I found it, it's called Aharonov-Bohm effect, and there has to be a magnetic field inside the obstacle

Anonymous at Tue, 30 Jul 2024 20:37:48 UTC No. 16303673

>>16303638
Btw. A is just supposed to be the set K. So it's really just this planar ring.

Anonymous at Tue, 30 Jul 2024 22:28:47 UTC No. 16303809

I wish I started learning math years ago. I thought it was knowledge reserved for the genius, and studying it was for the stupid to graduate.

Anonymous at Wed, 31 Jul 2024 09:26:52 UTC No. 16304441

Does anyone know how to prove that if we have one sequence [math]f_k[/math] of riemann integrable functions, such that [math]f = \sum_{k=0}^{\infty} f_k, a.e.[/math] and [math]\sum_{k=0}^\infty \int_{\mathbb{R}^n}|f_k(\textbf{x})| |d^n \textbf{x}| = \infty[/math] then for any other sequence, [math]g_k[/math] such that [math]f = \sum_{k=0}^{\infty} g_k, a.e.[/math] we must also have [math]\sum_{k=0}^\infty \int_{\mathbb{R}^n}|f_k(\textbf{x})| |d^n \textbf{x}| = \infty[/math], i.e. the series of integrals also can't converge.

I'm asking in the context of how the lebesgue integral is defined, in the image, as the sum of a series of integrals of riemann-integrable functions. How do we know the lebesgue integral doesn't exist, simply because we can find one such sequence whose series of integrals of absolute values don't converge. Maybe anothee sequence exists that does converge?

🗑️ Anonymous at Wed, 31 Jul 2024 11:30:24 UTC No. 16304516

>>16304441
Surely your theorem 4.11.7 answers this?

Anonymous at Wed, 31 Jul 2024 11:33:21 UTC No. 16304519

>>16304516
In theorem 4.11.7 the restriction that the integrals are finite is not necessary.
If that's proven in your book you can probably adapt the proof to show equality in [math][0,\infty)\cup\{\infty\}[/math].

Anonymous at Wed, 31 Jul 2024 11:49:34 UTC No. 16304526

>>16304519
This is the proof of theorem 4.11.7 and it looks like they do require the restriction that the series of integrals of absolute values are finite. Specifically in equation 4.11.24, am I wrong?

Anonymous at Wed, 31 Jul 2024 11:50:46 UTC No. 16304528

>>16304519
I forgot the screenshot

Anonymous at Wed, 31 Jul 2024 12:25:26 UTC No. 16304543

>>16304526
You're right, they do use it there. For Lebesgue integration theory it shouldn't be needed (as you're trying to now show), but adapting the given proof probably isn't going to be nice because the machinery they developed assumes finiteness or boundedness, it seems.

Anonymous at Wed, 31 Jul 2024 12:42:36 UTC No. 16304561

I bombed calc 2 many years ago and switched from CS to IT because of the math. Some issues included:
- The pace was really fucking fast and I learn nothing from lectures.
- Some type of calculation lab was used at the end of each lecture (Mathematica?).
- I had no idea what the textbook was saying so I was doing the shitty match-examples-to-problems technique.

I was wondering if relearning everything from Algebra up on my own would be worthwhile if I wanted a math-involved major. Or perhaps I need to change some fundamental way I learn and study.

Anonymous at Wed, 31 Jul 2024 12:50:28 UTC No. 16304568

Please help. There is something I'm messing up and I've been looking at this for like an hour.

Anonymous at Wed, 31 Jul 2024 12:59:11 UTC No. 16304571

>>16301714
I've got a stupid question.

I'm trying to work out how to do a Minkowski difference (or addition/sum?) in order to determine a circle is colliding within an area on a 2D plane in Python.

I've picked the following arbitrary values:
#Circle values
CirclePos = (30,40)
CircleRad = 5
#Area values
TopLeftArea = (100,140)
WidthHeight = (50,30)

I've tried to read up on it, but explanations are either incomplete, or they get too technical and I'm too retarded to understand how to convert maths formulae into code.

Could someone write a Python code/function with explanations on how to use Minkowski difference to determine if a circle is colliding with an area?

Anonymous at Wed, 31 Jul 2024 13:50:59 UTC No. 16304618

Oops, killed the thread.

Anonymous at Wed, 31 Jul 2024 14:53:31 UTC No. 16304661

>>16304568
Should be [math]f(x)[/math] on the left side of the first line. Because it's [math]f(x_0 + x - x_0)[/math]

Anonymous at Wed, 31 Jul 2024 15:03:57 UTC No. 16304668

>>16304661
Thank you. That was bothering me a lot.

Anonymous at Wed, 31 Jul 2024 16:48:33 UTC No. 16304743

>>16304543
Can you see how to prove it from the propositions and theorems in the image?

Anonymous at Wed, 31 Jul 2024 21:03:01 UTC No. 16304992

explain it without looking it up

Anonymous at Wed, 31 Jul 2024 22:54:52 UTC No. 16305112

Bump >>16304441

Anonymous at Wed, 31 Jul 2024 23:38:08 UTC No. 16305154

>>16304441
This is the most autistic definition of the Lebesgue integral I've ever seen, what kinda textbook for cryptids is this?

Anonymous at Wed, 31 Jul 2024 23:45:59 UTC No. 16305160

>>16305154
It's "Vector Calculus, Linear Algebra, and Differential Forms - A Unified Approach" by John H. Hubbard and Barbara Burke Hubbard.

Anonymous at Thu, 1 Aug 2024 00:24:16 UTC No. 16305198

>>16304441
That's not true, though. I think.
You can have a case like [math]n = 1[/math], [math]f_k = \left( - \dfrac{1}{\lfloor k/2 \rfloor} \right)^k \chi_{[0, 1]}[/math]

Anonymous at Thu, 1 Aug 2024 00:28:32 UTC No. 16305204

>>16304992
Instead of picturing light emmited from an object, reflecting, and hitting your eye, imagine you eye shooting out a beam of light.
The light hits the mirror at a steep angle, reflects off, and hits the egg
Since it hits the egg, you see the egg "straight" ahead of you, which is in the mirror.

Anonymous at Thu, 1 Aug 2024 00:31:50 UTC No. 16305209

>>16305198
What do you mean?

Anonymous at Thu, 1 Aug 2024 00:53:57 UTC No. 16305235

>>16305209
If we set [math]f_0 = 0[/math] (the value we set for f_0 is irrelevant but this makes the calculation more clear), we have [math]\displaystyle \sum_0^{\infty} f_k = 0[/math]. Approaches it uniformly too.
But the sum [math]\displaystyle \sum_{k = 0}^{\infty} \int_{\mathbb{R}} |f_k| d \mu[/math] is basically a harmonic series and diverges.

Anonymous at Thu, 1 Aug 2024 00:54:40 UTC No. 16305236

no /med/ so I ask
Could I mangle my face for it to look like skullface without dying of infection?

Anonymous at Thu, 1 Aug 2024 01:37:44 UTC No. 16305274

>>16305235
yoink

Anonymous at Thu, 1 Aug 2024 07:55:35 UTC No. 16305630

In proton conductors, is there any phenomenon analogous to superconductivity?

Anonymous at Thu, 1 Aug 2024 08:59:33 UTC No. 16305643

>>16305235
What am I missing?
[math]\sum_{k\geq2}\int_0^1|f_k| dx=\sum_{k\geq2}|\frac{1}{\lfloor k/2 \rfloor}|^k \leq \sum_{k\geq2}|\frac{1}{\lfloor k/2 \rfloor}|^2=\frac{\pi^2}{3}[/math]

Anonymous at Thu, 1 Aug 2024 09:14:59 UTC No. 16305651

>>16305235
What they said >>16305643

Anonymous at Thu, 1 Aug 2024 09:21:45 UTC No. 16305656

>>16304743
Not immediately.
I'd just let it go and learn Lebesgue integration / measure theory from a different point of view.
A big selling point is that the Riemann integral is not very generous when it comes to taking limits, but by defining your integrals in the way the book does you need to take a lot of limits under Riemann integrals to prove anything.
None of this is necessary or aids understanding, imo.

Anonymous at Thu, 1 Aug 2024 09:25:29 UTC No. 16305658

>>16305656
By the way, they don't actually explicitly state it in the book, and I'm beginning to think it's not actually true (as >>16305198 possibly pointed out). They say in the book that they get measure theory as a byproduct of their, non-standard, approach. The reason they did it this way was to make it more accessible to undergrads and to emphasize computationally effective algorithms, as this approach enables you to calculate the lebesgue integral I guess.

Anonymous at Thu, 1 Aug 2024 09:29:55 UTC No. 16305662

>>16305658
>this approach enables you to calculate the lebesgue integral I guess
I don't see how, unless there's a clear way to find a series of riemann-integrable functions equal to whatever function you want to integrate.

Anonymous at Thu, 1 Aug 2024 09:39:13 UTC No. 16305667

>>16305662

Anonymous at Thu, 1 Aug 2024 10:08:43 UTC No. 16305688

if an atom is entangles with some other atom

why isnt a flower entangled with a cat?

Anonymous at Thu, 1 Aug 2024 10:18:09 UTC No. 16305695

>>16305643
My bad, it's supposed to be [math]f_k = (-1)^k \left(\dfrac{1}{\lfloor k/2 \rfloor} \right) \chi_{[0, 1]}[/math] (so you get the harmonic series).
I don't know why I moved the -1^k inside the thingy.

Anonymous at Thu, 1 Aug 2024 14:30:46 UTC No. 16305864

>>16305688
Decoherence. If an entangled system was perfectly isolated it would remain that way forever. However at the macroscopic scale that is effectively impossible to achieve. So a single photon of sunlight, a single air molecule, a single thermal photon from the heat of the environment, any particle you can think of interacting with one of the countless particles in the cat or flower would instantly break the entanglement. The world we see around us is the statistical average of all their constituent wavefunctions being constantly measured.

Anonymous at Thu, 1 Aug 2024 17:55:05 UTC No. 16306046

>>16305630
Interesting question. If there was - and I'm not aware of any such material - then it would still be superconductivity. Just because the current is formed of something other than electrons would not make a difference. The problem is the lack of any coupling mechanism in such materials that would form something like Cooper Pairs. Even then because of their nature I suspect their critical temperature would be tiny.

Anonymous at Thu, 1 Aug 2024 18:25:52 UTC No. 16306067

>>16305667
Show Appendix 21. I still haven't been given a series of riemann integrable functions that equal to the rational/irrational between [0,1] function that maps to {0,1}

Anonymous at Thu, 1 Aug 2024 18:58:04 UTC No. 16306109

>>16306067
You can take [math](r_k)_k[/math] an enumeration of the rationals, and then [math]1_{\mathbb Q}=\sum_k 1_{\{r_k\}}[/math] and [math]1_{\mathbb Q^c}=1-\sum_k 1_{\{r_k\}}[/math].
>>16305695
That makes more sense (and works!), thanks.

Anonymous at Thu, 1 Aug 2024 22:16:50 UTC No. 16306277

>>16306109
oh that works

Anonymous at Fri, 2 Aug 2024 18:32:36 UTC No. 16307400

>>16301714
Suppose we have that [math]\sum_{k=1}^{\infty} \sum_{j=1}^{\infty} \int_{\mathbb{R}^n}|g_{k,j}(\textbf{x})| |d^n \textbf{x}| < \infty[/math]. Let [math]h_l = \sum_{j=1}^{l} g_{j, l-j+1}[/math]. Show that the series [math]\sum_{l=1}^{\infty} \int_{\mathbb{R}^n}|h_l(\textbf{x})| |d^n \textbf{x}|[/math] converges.

Anonymous at Fri, 2 Aug 2024 19:45:50 UTC No. 16307530

Bump >>16307400

Anonymous at Fri, 2 Aug 2024 20:12:37 UTC No. 16307580

>>16307400
[math]\sum_{l=1}^{\infty} \int_{\mathbb{R}^n}|h_l(\textbf{x})| |d^n \textbf{x}|\leq\sum_{l=1}^{\infty}\sum_{j=1}^l \int_{\mathbb{R}^n}|g_{j,l-j+1}(\textbf{x})| |d^n \textbf{x}|=\sum_{(k,j)\in\mathbb Z^2}\int_{\mathbb{R}^n}|g_{k,j}(\textbf{x})| |d^n \textbf{x}| < \infty[/math]

Anonymous at Fri, 2 Aug 2024 20:14:54 UTC No. 16307585

>>16307580
Could you explain the final equality (not the inequality)? I don't know how to rigorously show that.

Anonymous at Fri, 2 Aug 2024 20:16:42 UTC No. 16307589

>>16307580
I assume that's [math]\sum_{k=1}^{\infty} \sum_{j=1}^{\infty}[/math] right? In the term before [math]\infty[/math]

Anonymous at Fri, 2 Aug 2024 20:33:21 UTC No. 16307604

>>16307580
>>16307585
>>16307589
It depends on what you're comfortable with. All sums are the same in the sense that they all add each term once. Do you know the Riemann rearrangement theorem (or something similar)?
In essence, because you have absolute convergence of your sums rearrangements won't change the value.

Anonymous at Fri, 2 Aug 2024 20:36:30 UTC No. 16307609

>>16307604
I know that an absolutely convergent series can be rearranged and converge to the same value, but only for single series. I don't know about double series. Do we need a theorem about rearrangement of double series (seems a bit unfair as the book I'm reading has literally never talked about it).

If you want the full context, it's shown in the screenshot. It's in trying to prove this theorem.

Anonymous at Fri, 2 Aug 2024 20:37:31 UTC No. 16307610

>>16307604
If you want further context on how the lebesgue integral is defined in this book, see this screenshot >>16304441

Anonymous at Fri, 2 Aug 2024 20:46:21 UTC No. 16307619

>>16307609
>but only for single series
Like I said, it depends on what you're comfortable with. The (cartesian square of the) integers are in bijection with the positive numbers, so in some sense you have only one series.
You probably define a series as a limit of partial sums, so here you have two limits. Do you know something like https://en.wikipedia.org/wiki/Iterated_limit#Comparison_with_other_limits_in_multiple_variables ?

Anonymous at Fri, 2 Aug 2024 20:49:23 UTC No. 16307625

>>16307619
No, I haven't seen limits in two variables. Did the authors miss out on an important chunk of theory, or is it possible to prove without that?

Anonymous at Fri, 2 Aug 2024 20:51:49 UTC No. 16307627

>>16307619
I know about establishing a bijection between the cartesian pairs of natural numbers and the naturak numbers, like: (1,1), (1,2), (2,1), (1,3), (2,2), (3,1), ...

Anonymous at Fri, 2 Aug 2024 21:13:23 UTC No. 16307649

>>16307619
I've highlighted the relevant part of >>16307609 where the authors seem to mention the reordering of the sum, but is this just a single sum?

Anonymous at Fri, 2 Aug 2024 22:46:00 UTC No. 16307750

Bump >>16307400 >>16307609 >>16307625

Anonymous at Fri, 2 Aug 2024 22:50:41 UTC No. 16307755

>>16307750
You haven't noticed how slow this thread is have you?

Anonymous at Sat, 3 Aug 2024 08:10:00 UTC No. 16308247

>>16307649
It reads like the authors assume you're familiar already with sum rearrangements and when they are allowed.
>>16307627
That's the one they use, >>16307580 should have used positive numbers instead of integers, yes.
>>16307625
Try to prove that those two sums are equal to the one big sum over all pairs of integers. If you don't know how, see the Wikipedia link above, which should help.

Anonymous at Sat, 3 Aug 2024 08:17:47 UTC No. 16308250

>>16301714
What are people using for libgen nowadays? It's been a few yrs for me. Does libgen.rs still work?

Anonymous at Sat, 3 Aug 2024 09:03:44 UTC No. 16308265

>>16308250
yes

Anonymous at Sat, 3 Aug 2024 12:16:06 UTC No. 16308359

What are itches and what is the evolutionary purpose of scratching an itch?

🗑️ Anonymous at Sat, 3 Aug 2024 12:31:39 UTC No. 16308376

You put N random points inside a square. What is the expected radius of the largest possible circle that can exist in the square without overlapping with any of the points?

Anonymous at Sat, 3 Aug 2024 12:35:47 UTC No. 16308383

You put N random points inside a unit square. What is the expected radius of the largest possible circle that can exist in the square without overlapping with any of the points?

Anonymous at Sat, 3 Aug 2024 15:51:59 UTC No. 16308586

I haven't been on /sci/ in a while and I see more generals. Are there more successful general threads now or are these new ones just attempts?

Anonymous at Sat, 3 Aug 2024 18:03:27 UTC No. 16308724

Let G be a group and let A and B be two subsets of G of the same cardinality that both include the identity.

What is a fast way to determine whether or not there is a group automorphism of G that maps A to B?

Anonymous at Sat, 3 Aug 2024 18:59:43 UTC No. 16308771

What is accuracy and a truncation error in numerical methods? And how do i find them?

Anonymous at Sat, 3 Aug 2024 19:17:38 UTC No. 16308801

>>16308771
That's a complicated topic but it comes down to the fact that cpu floating point registers are finite in size. A loss of 'accuracy' is the stored value is not exact, certain values can only be stored as an approximation. For example take the value 1/3 = 0.333..., that would take an infinite amount of storage to precisely manipulate the number. Similarly if you tried to store 1234567890123456789012345678901234567890123456789123456789, there isn't enough fpu register bits to store that value so it will be truncated to something like 123456789 x 10^40

The field of numerical methods involves coming up with algorithms that reduce such problems and they may be cpu architecture dependant.

Anonymous at Sat, 3 Aug 2024 19:33:59 UTC No. 16308815

>>16308801
Holy shit thats a good explanation, thanks anon!

Anonymous at Sun, 4 Aug 2024 02:51:06 UTC No. 16309281

>>16308383
I believe with these questions you have to exploit the fact that E(X+Y)=EX+EY even if X and Y are not independent (where + means "integral"). For any R you can draw black disks of radius R around the points, and then ask what the expected value of the remaining white area is. Or given any point P in the square the expected number of sample points that are within distance R of P. I have some vague feeling that you can calculate the probability that there is a disc of radius R this way. I'm not sure about the details.

Anonymous at Sun, 4 Aug 2024 03:17:15 UTC No. 16309314

>>16308359
An itch sensation is an involuntary response that is triggered by a stimulus. The most obvious trigger is inflammation, which directs your focus to either a bite, a rash, or an allergy. The less obvious trigger is from your skin pores opening up rapidly due to a change in temperature. The reason why we want to itch a, well, "itch", is because instinct dictates that scratch off the problem would resolve the issue. However, the problem itself, where your body is producing the histamine, is subdermal, which is why scratching is a no-no as it damages the epidermis without solving the problem.

Anonymous at Sun, 4 Aug 2024 03:21:09 UTC No. 16309320

what is consciousness? I still don't understand what they mean.

Anonymous at Sun, 4 Aug 2024 04:06:01 UTC No. 16309377

>>16309320
> what is consciousness?
Since there isn't an agreed upon scientifically testable definition of consciousness, let alone an explanation, that makes your question kind of difficult to answer.

Anonymous at Sun, 4 Aug 2024 09:52:17 UTC No. 16309600

What is the functional difference between amphetamine and methamphetamine assuming both are pure and not street grade.

I mean specifically the effect they have. Im going to be prescribed adderal or vyvanse most likely and im wondering if its really that different from meth since i know meth is also sometimes used for adhd.

and like the side effects listed online for meth seem weird like it talks about teeth rotting and stuff but im curious if thats actually a side effect from meth or from just bad oral hygeine. the only thing i can sort of see is meth makes you horny maybe and amphetamine doesnt?

Anonymous at Sun, 4 Aug 2024 16:20:51 UTC No. 16309877

>>16309600
It's mostly the dose.

https://www.astralcodexten.com/p/know-your-amphetamines
>So abusers are taking about 25x a normal dose, and are usually snorting or injecting it. I think this explains the lion's share of the difference between "methamphetamine abuse" and "responsible Adderall use" without having to appeal to chemical differences between meth and unsubstituted amphetamines. Those differences do exist, and they're one reason why drug abusers prefer the methylated version. They're just not as dramatic as you would think from seeing a successful college student on Adderall vs. a toothless vagrant on meth.
(This blogger is a psychiatrist.)

Anonymous at Sun, 4 Aug 2024 18:07:22 UTC No. 16309980

>>16305160
That book is garbage. I don't know what Grant was trying to achieve by recommending this book to his viewers.

Garrote at Sun, 4 Aug 2024 18:07:43 UTC No. 16309982

I have biokinesis.

🗑️ Anonymous at Sun, 4 Aug 2024 18:55:06 UTC No. 16310073

Do numbers ending with seven have a tendency to be a prime number? I just check the numbers from 7 to 197 and I think at least half of them or more were prime numbers.

Anonymous at Sun, 4 Aug 2024 18:59:38 UTC No. 16310084

Do numbers ending with seven have a tendency to be a prime number? I just checked all the numbers ending with seven between zero and 200 and 60% of them were prime numbers.

Anonymous at Sun, 4 Aug 2024 19:03:57 UTC No. 16310090

>>16310084
I'll be honest with you. There's a slight risk because of 'such is such as' logic where they can just keep living many years. I had to make sure, and now I am sorting myself to come back. Fear not about betrayal, but you're probably gonna be ok. I'm on my way. I won't be long

Anonymous at Sun, 4 Aug 2024 19:04:27 UTC No. 16310091

>>16310084
I think they are more likely to be prime numbers then numbers ending in 0,2,4,5,6 or 8 at least.

Anonymous at Sun, 4 Aug 2024 19:06:24 UTC No. 16310093

>>16310090
Don't fuck with anything. Just relax. It's very very probably no. The small chance they equalize me on intelligence is probably not going to happen even as such as, as said, I'll be there soon. Don't fuck with anything I did.

Anonymous at Sun, 4 Aug 2024 19:08:53 UTC No. 16310099

>>16310090
In my mind it says I'm almost back or back now. I'm not well informed about what's going on hence a bit of error in my posts. What you stand on is very powerful, given that war is extremely hard to achieve with you, it's probably best not to react to anything going on with that. If the small chance that war actually does come does happen - that's the slight risk.

Anonymous at Sun, 4 Aug 2024 20:25:17 UTC No. 16310179

Is there any way to differentiate the cells made by mitosis? Is there always a distinct cell A and cell B, or "master" cell vs "slave," or are they indistinguishable?

Anonymous at Sun, 4 Aug 2024 21:33:47 UTC No. 16310251

>>16308724
Well, the easiest way to prove that there's no automorphism is looking at element orders. Then, using the same trick again to look at possible automorphisms.

Anonymous at Mon, 5 Aug 2024 00:22:36 UTC No. 16310390

>>16310084
There's nothing particularly special about 7 in this regard; the same is true of 3.
And for 1 and 9, it's still 50%, and part of that is just because 1 and 9 are themselves not prime.

Anonymous at Mon, 5 Aug 2024 00:53:05 UTC No. 16310414

>>16309877
oh, thanks. ii read that meth is also stronger acting on the reward centre but that also seems like it could be dose dependant. kind of like how my olanzapine equivalent to quetiapine is 7.5 vs 100mg

Anonymous at Mon, 5 Aug 2024 02:37:07 UTC No. 16310493

How feasible is it for someone to teach themselves calculus? I haven't taken a proper math course in about 10 years. I think it was trig.

Anonymous at Mon, 5 Aug 2024 03:50:54 UTC No. 16310542

>>16310414
If you want more reading, this guy's community (in the comments and its subreddit) is also into self-experimenting with drugs and they discuss scientific papers, experiences and anecdotes.

>The subjective difference between these two amphetamine preparations was that meth-, at the appropriate (read: low) dose, was significantly “clearer,” which I attributed to the main noticeable difference: low/no “body load,” as defined by tachycardia, muscle tension, and food tolerance/GI upset.

>Adderall definitely feels like the most "stimmy" of the prescribed stimulants. The l-enantiomer supposedly interacts with NET and gives you that jittery physical stimulation whereas d-amphetamine is more selective for DAT, making it smoother.

https://old.reddit.com/r/slatestarcodex/comments/l4sk1r/know_your_amphetamines/

(haven't read it myself)

🗑️ Anonymous at Mon, 5 Aug 2024 03:57:02 UTC No. 16310550

>>16310084
In the long run, no. By

https://en.wikipedia.org/wiki/Dirichlet%27s_theorem_on_arithmetic_progressions#Distribution

the density of primes among the numbers that end in 7 is [math]\frac{\varphi(10)}{\ln n}[/math] which is [math]\frac{1}{4\ln n}[/math] just like for 1, 3, and 9.

🗑️ Anonymous at Mon, 5 Aug 2024 03:59:27 UTC No. 16310553

>>16310084
In the long run, no. By

https://en.wikipedia.org/wiki/Dirichlet%27s_theorem_on_arithmetic_progressions#Distribution

the density of primes among the numbers that end in 7 is [math]\frac{1}{\varphi(10)\ln n}[/math] which is [math]\frac{1}{4\ln n}[/math] just like for 1, 3, and 9.

Anonymous at Mon, 5 Aug 2024 11:35:30 UTC No. 16310820

>>16310493
depends on how far you want to go
if it's calc for babies, extremely. brush up on elementary algebra and trig first and you should be golden

Anonymous at Mon, 5 Aug 2024 12:55:32 UTC No. 16310861

>>16310493
i crammed calculus in 2 weeks for an exam. that i didnt go to the classes for and i got a 70, so i think you should be able to do it. recently i was reading a book called the theoretical minimum and it had an ok calc refresher. calculus isnt actually that hard unless theres some stuff i just never covered (i did an engineering degree)
>>16310542
this seems a bit schizo with the name and slight esotericism but i will look into it

Anonymous at Mon, 5 Aug 2024 14:03:05 UTC No. 16310897

If you have a function f(x, y) of two variables can you always decompose it into two other functions g(x) and h(y) which only depend on either x or y? If no, would it maybe work if the function f was continuous and what's are the weakest restrictions on f such that this works out?

Anonymous at Mon, 5 Aug 2024 16:41:55 UTC No. 16311037

>>16305160
Stop reading meme books. If you want a fast course in general measure theory, read chapter 2 of Federer. For a full course read Bogachev

Anonymous at Mon, 5 Aug 2024 16:42:56 UTC No. 16311039

>>16304441
you're confused because you're reading a shit book that glosses over important facts

Anonymous at Mon, 5 Aug 2024 16:44:29 UTC No. 16311042

>>16301723
Sternberg. Lectures on differential geometry

Anonymous at Mon, 5 Aug 2024 16:47:31 UTC No. 16311046

>>16309980
Grant doesn't know much math, that's the issue.

Anonymous at Mon, 5 Aug 2024 18:39:18 UTC No. 16311199

>>16310897
No, but you can do currying, which is related.
https://en.wikipedia.org/wiki/Currying#:~:text=In%20mathematics%20and%20computer%20science,and%20produces%20objects%20in

Anonymous at Tue, 6 Aug 2024 01:53:10 UTC No. 16311668

Why’s Elon shilling for the CIA? I thought he was cool.

Anonymous at Tue, 6 Aug 2024 02:55:06 UTC No. 16311719

What would happen if the solar system was covered by a big cloud of dust that blocked the light of other stars? Not dispersed throughout the solar system, but in a kind of hollow sphere enclosing it.

Anonymous at Tue, 6 Aug 2024 05:05:15 UTC No. 16311811

>>16310493
Read Lang's Basic Math, then Apostol

Anonymous at Tue, 6 Aug 2024 05:06:11 UTC No. 16311812

>>16311719
It'd be sorta lame trying to use a telescope

Anonymous at Tue, 6 Aug 2024 05:14:25 UTC No. 16311816

>>16305658
>more accessible to undergrads
measure theory literally is undergrad shit. I remember doing it in my second or third semester. What the fuck is inaccessible about it? Those basic definitions (algebra/ring of sets, measure, etc.) require nothing but knowledge of basic set theory lol

Anonymous at Tue, 6 Aug 2024 05:32:19 UTC No. 16311828

>>16306277
are you retarded

Anonymous at Tue, 6 Aug 2024 05:33:49 UTC No. 16311830

>>16309600
the difference is that the methyl group allows the molecule to pass the blood brain barrier much more easily

Anonymous at Tue, 6 Aug 2024 06:44:07 UTC No. 16311885

>>16304441
wtf is that notation for differentials

Anonymous at Tue, 6 Aug 2024 07:59:23 UTC No. 16311941

>>16311830
ohh interesting, how does that work?

Anonymous at Tue, 6 Aug 2024 08:17:13 UTC No. 16311958

>>16311812
would it cause the inside of the solar system to heat up?
>It'd be sorta lame trying to use a telescope
could it see stuff within the solar system still? Like planets and any lights inside the sphere

Anonymous at Tue, 6 Aug 2024 12:54:19 UTC No. 16312146

>>16301714
I need some help creating a electronic differential, I found this paper
https://www.emo.org.tr/ekler/7433f59020ec6bf_ek.pdf
that has all the equations needed but I cant replicate the results with my python code but I dont know where is wrong I dont know If anyone here can guide me
[code]
import math


class Carro:
L = 2.285
lr = 0.835
dr = 1.35
r = 0.395
K = 1.21

def calc_deltas(self, delta: float):
p1 = self.L * math.tan(delta)
p2 = self.L - ((self.K / 2) * math.tan(delta))
self.d1 = math.atan(p1 / p2) if p2 != 0 else 0
p3 = self.L + ((self.K / 2) * math.tan(delta))
self.d2 = math.atan(p1 / p3) if p3 != 0 else 0

def calc_rad(self, delta: float):
# Ensure delta is not zero to avoid division by zero
self.r1 = self.r2 = self.L / math.sin(delta)
# self.r1 = self.r2 = 1
self.r3 = (self.L / math.tan(delta)) - (self.dr / 2)
self.r4 = (self.L / math.tan(delta)) + (self.dr / 2)
print(f"""
Rad 1: {self.r1}
Rad 2: {self.r2}
Rad 3: {self.r3}
Rad 4: {self.r4}
""")
p1 = (self.r3 + (self.dr / 2)) ** 2
p2 = self.lr**2
self.R_cg = math.sqrt(p1 + p2)

def calc_ang_vel(self, V: float):
if self.R_cg != 0:
self.w1 = (V * self.R_cg) / (self.r1 * self.r)
self.w2 = (V * self.r2) / (self.R_cg * self.r)
self.w3 = (V * self.r3) / (self.R_cg * self.r)
self.w3 = (V * self.R_cg) / (self.r3 * self.r)
self.w4 = (V * self.r4) / (self.R_cg * self.r)
else:
self.w1 = self.w2 = self.w3 = self.w4 = 0

print("Angular Velocities:")
print(f"w1: {self.w1}")
print(f"w2: {self.w2}")
print(f"w3: {self.w3}")
print(f"w4: {self.w4}")


c = Carro()
delta = 1
c.calc_deltas(delta)
c.calc_rad(delta)
velocida = 50
c.calc_ang_vel(velocida)
[/code]
Someone on /g/ said this >>>/g/101723430 but I still cant figure it out

Anonymous at Tue, 6 Aug 2024 16:05:08 UTC No. 16312323

>>16312146
Your w1 & w3 values are wrong. R_cg is always the denominator. You also set w3 twice, overriding it with the wrong value.

Anonymous at Tue, 6 Aug 2024 17:21:43 UTC No. 16312376

>>16312323
Yeah dumb me I put that there for testing, but even with the corrected values I git the same result the other anon got, a value of 1278 of angular velocity

import math


class Carro:
L = 2.285
lr = 0.835
dr = 1.35
r = 0.395
K = 1.21

def calc_deltas(self, delta: float):
p1 = self.L * math.tan(delta)
p2 = self.L - ((self.K / 2) * math.tan(delta))
self.d1 = math.atan(p1 / p2) if p2 != 0 else 0
p3 = self.L + ((self.K / 2) * math.tan(delta))
self.d2 = math.atan(p1 / p3) if p3 != 0 else 0

def calc_rad(self, delta: float):
# Ensure delta is not zero to avoid division by zero
self.r1 = self.r2 = self.L / math.sin(delta)
# self.r1 = self.r2 = 1
self.r3 = (self.L / math.tan(delta)) - (self.dr / 2)
self.r4 = (self.L / math.tan(delta)) + (self.dr / 2)
print(f"""
Rad 1: {self.r1}
Rad 2: {self.r2}
Rad 3: {self.r3}
Rad 4: {self.r4}
""")
p1 = (self.r3 + (self.dr / 2)) ** 2
p2 = self.lr**2
self.R_cg = math.sqrt(p1 + p2)

def calc_ang_vel(self, V: float):
if self.R_cg != 0:
self.w1 = (V * self.r1) / (self.R_cg * self.r)
self.w2 = (V * self.r2) / (self.R_cg * self.r)
self.w3 = (V * self.r3) / (self.R_cg * self.r)
self.w4 = (V * self.r4) / (self.R_cg * self.r)
else:
self.w1 = self.w2 = self.w3 = self.w4 = 0

print("Angular Velocities:")
print(f"w1: {self.w1}")
print(f"w2: {self.w2}")
print(f"w3: {self.w3}")
print(f"w4: {self.w4}")


c = Carro()
delta = 1
delta = math.radians(delta)
c.calc_deltas(delta)
c.calc_rad(delta)
velocida = 50
c.calc_ang_vel(velocida)

Anonymous at Tue, 6 Aug 2024 19:14:27 UTC No. 16312505

>>16311958
>could it see stuff within the solar system still? Like planets and any lights inside the sphere
Sure, until the dust starts colliding and loses orbital momentum and comes crashing in to us and fucking up our shit.

Anonymous at Wed, 7 Aug 2024 08:38:40 UTC No. 16313197

>>16301714
how do you go from knowing absolutely nothing about math "not knowing even how to do basic division correctly" to having a basic understanding the basics of linear algebra while being kind of a retard?

Anonymous at Wed, 7 Aug 2024 09:14:44 UTC No. 16313209

>>16312376
Probably because the paper isn't giving you all the the required calculations. For one the deltas are never shown used in any formula despite the fact they will be needed, nor how each of the 4 wheel velocities are combined to give the shown single rpm value. There are two tables of results for different wheel configurations but no description how the calculations differ for each.

Anonymous at Wed, 7 Aug 2024 13:29:33 UTC No. 16313416

If we can come up with a hydrophobic covering for things like torpedoes to have little to no drag in the water and be able to just slice through them like it's nothing. Why can't we come up with an oxygenphobic solution to put on cars, planes, tanks, horses, buses, trains etc. and make them reach sonic speed no problem? Just how many magnitudes harder is it to make an oxygen repellent thing over a water repellent thing?

Anonymous at Wed, 7 Aug 2024 14:20:09 UTC No. 16313446

these are 10 euros in my country, can they be useful for anything like distillation or idk
or are they no better than a glass jar or jug

Anonymous at Wed, 7 Aug 2024 14:21:29 UTC No. 16313447

it's borosilicate glass

Anonymous at Wed, 7 Aug 2024 14:23:25 UTC No. 16313451

maybe i could put a beverage with ice in it to be comfy during the summer

Anonymous at Wed, 7 Aug 2024 14:28:30 UTC No. 16313461

or would it be better to use a water bottle like athletes use

Anonymous at Wed, 7 Aug 2024 14:35:26 UTC No. 16313465

fml they already fixed the pricing mistake except for the pink one

Anonymous at Wed, 7 Aug 2024 16:58:30 UTC No. 16313654

>>16313416
Afaik, the fastest torpedoes use a jet of air or something like it in order to put a bubble ahead of it. Supercavitating torpedoes.

Anonymous at Wed, 7 Aug 2024 19:30:30 UTC No. 16313934

>>16313197
Get a tutor and go through K1-12 together. It is possible to self-study using textbooks, but only if you can tell whether you understand something or not. Most people can't, that's why they need a tutor.

You don't need to know how to do division by the way. You only need to know what it means to divide a number by another number. People barely do any calculations anyway, it's only the ideas that matter.

Anonymous at Thu, 8 Aug 2024 06:52:53 UTC No. 16314696

>>16313197
https://sheafification.com/the-fast-track/

Anonymous at Thu, 8 Aug 2024 07:01:38 UTC No. 16314706

>>16313934
disagree. Knowing how to do the exercises usually is a fairly good metric for how well you understand it

Anonymous at Thu, 8 Aug 2024 08:47:43 UTC No. 16314769

>>16314696
Is that your own blog or something? Because that's a shit list.

Anonymous at Thu, 8 Aug 2024 10:03:56 UTC No. 16314814

I recently started teaching myself math from the absolute very beginning from scratch. And I reached the first potential stumbling block of something that needs to be corrected in my understanding.

I got to the section on multiplying fractions. I get how it works mathematically, but I don't understand what is actually happening. Like, I was led to believe in my shitty American education system that multiplication as an operation was an increase in something. Like, "increase" in a positive direction is an inherent part of multiplying.
So I don't understand that when you multiply a fraction by a fraction, you get less of it. Now obviously I could just accept this and move on, but I want to actually understand why this works this way. Because I don't understand why the operation of multiplying fractions leads to a smaller amount. I get you just multiply the numerators by the numerators, etc. and just reduce it. It's just the internal working of what's happening I don't understand.

Anonymous at Thu, 8 Aug 2024 10:38:10 UTC No. 16314857

>>16314769
newfaggot

Anonymous at Thu, 8 Aug 2024 10:39:21 UTC No. 16314858

>>16314814
>Like, "increase" in a positive direction is an inherent part of multiplying.
That's addition. You can think of multiplying as instead "scaling". Stretching or shrinking along the number line depending on the values involved.

> So I don't understand that when you multiply a fraction by a fraction, you get less of it.
All numbers are fractions, it's just that some have a denominator of 1. Also you only get 'less' if one of the fractions is less than 1.

> It's just the internal working of what's happening I don't understand.
I always liked the cake analogy as a kid. If you multiply x (the cake) by the fraction n / d, you are cutting the cake into 'd' slices and keeping 'n' of them. This also works if x is a fraction.

Anonymous at Thu, 8 Aug 2024 10:41:57 UTC No. 16314861

>>16314696
based list

Anonymous at Thu, 8 Aug 2024 10:54:25 UTC No. 16314868

>>16314858
Thanks for the response. I kind of suspected this was how to look at it, but it's still hard to deprogram my brain and rethink it like this. So basically, just think of multiplication as not necessarily increase in a positive direction, but "increase" in the direction of whatever is being multiplied (in the case of fractions, a decrease)?

Anonymous at Thu, 8 Aug 2024 11:03:38 UTC No. 16314879

Isn't (1,3)*(1,2)(3,4) = (1,2,3,4) ?

It's like every time the order of factors matters Maple gives the wrong result.

Anonymous at Thu, 8 Aug 2024 11:07:40 UTC No. 16314883

>>16314858
Also to add another thing I thought of. I looked at it again. Tell me if this is an accurate way to think about it.

I think of each fraction as a unit in its own right. Like say 1/4 is just a starting point of 1 unit. 1/4 is obviously part of some greater whole of 1 but temporarily the 1/4 is a "whole." And then with that "1" of 1/4 you can do the multiplication with it that you would just do with whole numbers. So for example, multiplying 1/4 by 1/2 gives you 1/8 because it's just doing the same operation it would have done to a whole number (like 2/1).

This might be confusing and I'm probably not explaining my thought process correctly, but this is how I'm visually seeing how it works.

Anonymous at Thu, 8 Aug 2024 11:20:52 UTC No. 16314893

>>16314883
This is mostly schizo bullshit. Sorry, I'm half asleep.

The way I see it is to multiply starting at the initial fraction TOWARDS zero. And then take that distance and match it up with the value that is after 0.
For example, you start at 1/2 and you multiply by 1/4. If 1/2 is seen as a unit, and you flip it upside down, the distance from 1/2 to 0 is "1," so 1/4 of that 1 is the distance from 4/8 to 3/8, and that distance would just be matched up to the first type of that unit from 0, in this case 1/8, the correct answer.

This is my last post, but this is how I visualize it.

Anonymous at Thu, 8 Aug 2024 11:22:49 UTC No. 16314896

>>16314883
>>16314893
If it works for you, you can visualize however you want. You're right though, it does read a bit schizo. Personally I'll stick to cake.

Anonymous at Thu, 8 Aug 2024 11:48:35 UTC No. 16314907

>>16314896
Yeah I don't think I get it. I don't get your cake analogy either. I just don't understand how multiplication can be a decrease. It makes zero intuitive sense. I guess I'm retarded. Feels bad man.

Anonymous at Thu, 8 Aug 2024 11:55:37 UTC No. 16314919

>>16314907
nta but think of multiplication as scaling. The entire analogy with counting apples and whatnot breaks down if you work with a set that is not discrete (i.e. the rational numbers).

Anonymous at Thu, 8 Aug 2024 12:40:44 UTC No. 16314979

>>16314907
> I just don't understand how multiplication can be a decrease
You don't understand if you cut something in half it becomes smaller?

Anonymous at Thu, 8 Aug 2024 15:15:23 UTC No. 16315170

>>16314706
I agree, but people literally don't know if they did the exercise correctly.

With calculations you can check if you got the right answer, but with proofs, people can't even tell. They need someone to tell them. It's insane.

Anonymous at Thu, 8 Aug 2024 15:34:16 UTC No. 16315207

>>16314883
This seems fine to me, but a laborious way to think about it.
You're essentially saying that [math]\frac{a}{b}\cdot\frac{c}{d}=(a\cdot\frac{c}{d})\cdot\frac{1}{b}[/math].

Maybe you like this:
(I'm assuming you know how to actually multiply two fractions (multiply the top numbers and the bottom numbers).)
''Multiplying by a fraction'' is, essentially, doing two things at the same time: multiplying by the top number, and dividing by the bottom number.
So, if the bottom number is larger, you're dividing more than you're multiplying and your result decreases.

As an example, suppose you have a pizza and you're dividing it among four people.
Everyone gets a quarter ([math]=0.25=\frac14[/math]) pizza.
The units here are [math]\frac{\text{pizza}}{\text{person}}[/math] (pizzas per person).
Suppose you get another pizza, then the amount of pizzas doubles and so everyone gets [math]\frac14\cdot2=\frac12[/math] pizza, as you'd expect.
If more people show up, and you now have 12 people (so the number of people tripled), every bit of pizza has to be divided among three times the people; everyone gets [math]\frac14 / 3 = \frac14 \cdot\frac13=\frac1{12}[/math] pizza.
So, if you start with one pizza for four people, and you double the amount of pizzas while multiplying the amount of people by three, you end up with [math]\frac{1}{4}\cdot \frac{2}{3}=\frac{2}{12}[/math] pizza per person.
You multiply by two, which does indeed only make the amount increase, but you also have more people show up, so everyone only gets two thirds of the pizza they'd originally have gotten (you multiply by [math]\frac23[/math]).

Anonymous at Thu, 8 Aug 2024 21:05:58 UTC No. 16315623

>>16314979
I do. But I don't get how that is "multiplying."

>>16315207
Thanks for the effort post. I was away for a bit but looked at it again and I think I get it now. It's the mathematical manipulation of the terms that made me see how it works on a deeper level. Like how a fraction multiplication problem can just turn into a division (e.g. how 4 x 1/2 becomes 4/2 making it more intuitive). So doing that I can see the inner workings of why it makes sense. Division in this case seems more intuitive to me because that looks more like what is actually happening (if you are cutting something in half you are dividing it).
As for your pizza analogy, sorry for being retarded, but I don't understand it that way. I can see how you can divide up a pizza. That is something that is very tangible and observable. But I don't see how the inverse operation is observable (i.e. "multiplying a part of it"). Everyone says "Let's divide up this pizza among ourselves," not "Let's multiply parts of this pizza among ourselves." I don't see how these two things are the same action. It actually breaks my brain thinking about it. I will just have to accept that I only get the math behind it.

Anonymous at Thu, 8 Aug 2024 21:47:38 UTC No. 16315682

>>16315623
I think you should get rid of the intuition that by "multiplying" something, it becomes "larger".
I mean, what if you multiply a number by 0, or by -1? Those aren't fractions.

As for the pizza business, I tried to cook up an example (1 pizza for 4 people) where a change of units (which is just a multiplication) results in people ending up with less pizza per person (ie a multiplication can make something smaller).
>not "Let's multiply parts of this pizza among ourselves.
The multiplication happens in the units (1 pizza gets doubled to become 2, and 4 people get tripled to become 12).
Then, you start with [math]\frac14 \frac{\text{pizza}}{\text{person}}[/math] but after the changes (more pizza and more people) you have to measure in the units [math]\frac{2\text{pizza}}{3\text{person}}[/math] to find everyone has [math]\frac14\frac{2\text{pizza}}{3\text{person}}=\frac2{12}\frac{\text{pizza}}{\text{person}}[/math].
In words, everyone says "let's multiply the amount of pizza by 2, and the amount of people by 3." Then the amount of pizza per person gets multiplied by [math]\frac23[/math].

>I will just have to accept that I only get the math behind it.
I think this is common. There's this nice saying (by von Neumann, I think?) that "you don't understand things in mathematics, you just get used to them", and, honestly, if it takes me a thousand characters to elaborate on how fractions work, maybe I don't understand them.

Anonymous at Fri, 9 Aug 2024 02:54:27 UTC No. 16316193

Give the simplest example of an injective function from R^n -> R that you can think of, where n is a finite number > 1. Maybe n = 3

Can you extend this to complex numbers C^n -> R or C^n -> C

Anonymous at Fri, 9 Aug 2024 04:43:51 UTC No. 16316280

>>16316193
>Give the simplest example of an injective function from R^n -> R that you can think of, where n is a finite number > 1. Maybe n = 3
R can be injected into the set of 0-1 sequences like in Cantor's diagonal argument.
You can combine all n 0-1 sequence into a single sequences where each term takes values in {0,1,... 2^(n-1)}. (think binary)
Such a sequence (a_k) can be transformed into a real number in [0,1] again [math]\sum_{k=0}^\infty a_k 2^{-nk} [/math]
>Can you extend this to complex numbers C^n -> R or C^n -> C
C^n is just R^(2n)

Anonymous at Fri, 9 Aug 2024 05:51:28 UTC No. 16316323

>>16315623
Stop trolling

🗑️ Anonymous at Fri, 9 Aug 2024 07:02:35 UTC No. 16316404

A hyperbolic-parab surface is something like (x,y, z=x^2 - y^2). The level curves x^2-y^2 = const z can be assigned a tangent vector at each point. Taking a derivative you get the differential equation y'/x' = x/y, so your vector can be (y,x) or (-y,-x). To each point then, you can assign a different vector orthogonal to this tangent vector, so something like (-x,y) or (x,-y), which means you can get the differential equation y'/x' = -y/x whose solutions xy = const z are orthogonal to the original level curves.

That's pretty simple, but wth is this guy doing?

The direction/ray r' or r = (-b,a) is a vector pointing in a direction
X_u is the partial of the vector valued func. X with respect to u
E = < X_u, X_u > (dot product)
F = < X_u, X_v >
G = < X_v, X_v >
The magnitude-squared of the tangent velocity vector of a curve is then equal to E(u')^2 + Fu'v' + G(v')^2. This is the only time I know of where (E,F,G) is dotted with something. Idk how relevant this point is.

Im confused about the part in the middle where he says that since r and r' (the directions) are orthogonal, then you got E(av) + F(bv+au) + G(bu) = 0. Where is he getting (av, bv+au, bu) from, and why is he dotting it with (E,F,G)?

🗑️ Anonymous at Fri, 9 Aug 2024 07:07:30 UTC No. 16316411

I meant (b,-a). It comes from like ax' + by' = 0

Anonymous at Fri, 9 Aug 2024 12:24:29 UTC No. 16316672

>>16301714
Is it possible that "consciousness" is "simpler" than what we think it is?
In the way I'm asking, consciousness means to want something and to have that want drive evolution in a purposeful manner. I do not mean purpose in a supernatural way -- it's contained within the system.
For example, could it be possible that whatever evolved the ability to fly, it's ascendants had a "want" to fly?
Of course, those ascendants were extremely more "simple" than us. Which could mean that random evolution is the only way it happened.
But what about baser functions? To eat, to digest, to poop, to move, to see, to think.
Did a photon hit a receptive neuron in just the right way that made it excited and then cascade down that information to the point it mutated so their descendants eventually evolved sight?

Anonymous at Fri, 9 Aug 2024 14:10:53 UTC No. 16316868

How do you prove this?
I don't get the official solution from the book.

Anonymous at Fri, 9 Aug 2024 14:23:28 UTC No. 16316909

>>16316868
The statement is false. Here is a counterexample: take H' = G and let H be some non-normal subgroup of G.

Anonymous at Fri, 9 Aug 2024 15:43:22 UTC No. 16317058

>>16316868
This is why you read Lang instead. Algebra books are usually piss poor and have hardly improved since lang

Anonymous at Fri, 9 Aug 2024 16:25:27 UTC No. 16317125

>>16316868
That intersection is contained in the normal subgroup. You know, if something is true for every element in A, then it's also true for every element in any subset of A

Anonymous at Fri, 9 Aug 2024 16:44:43 UTC No. 16317170

>>16315170
Tbh I never got much out of having my assignments graded at uni. I only got better at math by extensively studying proofs in books and memorizing useful approaches. And now that I've graded assignments myself, I know that most just struggle with the language and don't even know what they're asked of. At that point, it's useless to tell them they're doing everything wrong. I guess a tutor could still do more than that but imo there's no way around studying on your own. My guess is most of these people just have some sort of undiagnosed ADHD preventing them to just sit down and read carefully

Anonymous at Fri, 9 Aug 2024 17:04:16 UTC No. 16317211

>>16317125
Obviously. That's not the question.
The question is what it has to do with normal subgroups.

>>16316868
Here's a newsflash: hG=G=Gh is always true for any element h of a group G, so the statement hG=Gh tells you nothing.
Please don't use that book, and make a note to avoid books from that publisher.

Anonymous at Fri, 9 Aug 2024 17:16:12 UTC No. 16317234

How do I prove the global stability of the fixed point?

Anonymous at Fri, 9 Aug 2024 17:19:52 UTC No. 16317247

>>16316868
>common core abstract algebra

Anonymous at Fri, 9 Aug 2024 17:50:08 UTC No. 16317307

>>16316280
>C is just R^2
no it's not, because the multiplication works differently

Anonymous at Fri, 9 Aug 2024 18:05:18 UTC No. 16317337

>>16317307
Nta but the ring structure is clearly irrelevant if you only care about injectivity, which is a set theoretic property

Anonymous at Fri, 9 Aug 2024 19:36:46 UTC No. 16317474

>>16301714
Why is Pi inherently 3.14... why is the ratio of a circumference to a diameter not another number? Why specifically is our universe created in a way such that pi is 3.14 and can it be a different ratio in another world?

Anonymous at Fri, 9 Aug 2024 19:53:13 UTC No. 16317505

>>16317474
It can be another value even in this world. Depends on how you define distance.
For example, if you replace your usual definition of distance with the taxicab metric (diagonal lines not allowed - straight across or straight down only, adding up distances horizontally and vertically to receive your total, so for example (0,0) and (1,1) would be at a distance of 2 from each other), π is 4.

Anonymous at Fri, 9 Aug 2024 20:37:18 UTC No. 16317569

>>16317474
Because geometry. Once you define pi to be the ratio of the circumference of a circle to its radius in flat euclidean space you are fixing its value. The number 3.14... then arises from some simple trigonometry. The inverse of arctan is a common example, but there are tens, if not hundreds of formula to calculate the value.

Anonymous at Fri, 9 Aug 2024 20:54:37 UTC No. 16317590

>>16317569
Why should a basic geometric construction, like a circle, like pi, appear in so many different fields?

Anonymous at Fri, 9 Aug 2024 20:57:42 UTC No. 16317592

It's basically this 'bossing' game of a universe where every individual is programmed and you can join, tip off and much more (anything). But characters are well done, if you give the one who is me a foolish death, you get score on how well it was.

Anonymous at Fri, 9 Aug 2024 21:00:00 UTC No. 16317594

>prototypical businessman

Designs very good proto products, low technicality but high grade. That's one of my two professions.

Anonymous at Fri, 9 Aug 2024 21:04:58 UTC No. 16317605

>>16317594
>grand politician

Anonymous at Fri, 9 Aug 2024 21:08:21 UTC No. 16317610

>>16317605
Yes, like the beast.

Anonymous at Fri, 9 Aug 2024 21:31:07 UTC No. 16317640

>>16317590
Because functions like sin, cos and more generally 'e' appear everywhere in the mathematics we use in those fields. One use start using such functions then it's a direct consequence that pi will also appear.

Anonymous at Fri, 9 Aug 2024 23:25:24 UTC No. 16317809

>>16301714
what exactly happens to the microwaves inside an oven once the timer hits zero? does it just magically disappear or turn into another form?

Anonymous at Fri, 9 Aug 2024 23:39:20 UTC No. 16317840

>>16317809
They'll bounce around inside the cavity before being absorbed within a fraction of a second.

Anonymous at Fri, 9 Aug 2024 23:45:14 UTC No. 16317852

where do I find fMRI's of the brain performing certain tasks? what words do I search for in scihub?

Anonymous at Sat, 10 Aug 2024 00:10:10 UTC No. 16317891

>>16317840
Absorbed by what?

It can't be the food since the food only heats up because of the movement of water molecules trying to align themselves to the microwaves

Anonymous at Sat, 10 Aug 2024 00:23:21 UTC No. 16317917

>>16317891
What energy isn't used to heat the food gets absorbed by the microwave itself. It's why you aren't supposed to leave an empty microwave running, it'll eventually heat up the device itself and damage it.

Anonymous at Sat, 10 Aug 2024 07:05:17 UTC No. 16318317

>>16301714
>4chan-science.fandom.com/wiki//sci/_Wiki
4chan-related wikis are getting axed, apparently
>>>/lit/23677602

Anonymous at Sat, 10 Aug 2024 07:14:38 UTC No. 16318325

>>16318317
Apparently there's functionality for generating a 'database dump' (https://community.fandom.com/wiki/Help:Database_download) but the only admin who can request it hasn't edited in over a decade (https://4chan-science.fandom.com/wiki/Special:ListUsers?group=sysop).

Anonymous at Sat, 10 Aug 2024 10:31:31 UTC No. 16318429

How does the dual have four vertices when number of faces is three, not four.

Anonymous at Sat, 10 Aug 2024 10:39:19 UTC No. 16318434

>>16318429
The infinite part outside a graph is considered a face also.

Anonymous at Sat, 10 Aug 2024 19:35:22 UTC No. 16319014

I bought these methylsulfonylmethane pills (completely legal supplement where I live) but they're way too big to swallow, harder than concrete so I can't crush them and they don't dissolve in water either. Is there any chemist here that can tell which ingredient to add so that it dissolves and I can just drink the powder?

Ingredients as displayed on the bottle: Methylsulfonylmethane, microcrystalline cellulose, silica, magnesiumstearate, hydroxy propyl cellulose, hydroxy propyl methyl cellulose.

Anonymous at Sat, 10 Aug 2024 19:48:54 UTC No. 16319032

>>16319014
I guess they are... a tough pill to swallow

Anonymous at Sat, 10 Aug 2024 20:44:37 UTC No. 16319100

>>16318434
What a stupid ass bullshit.

Anonymous at Sat, 10 Aug 2024 20:57:53 UTC No. 16319117

>>16319100
The dual of the dual must be isomorphic to the original graph or it would be useless.

Anonymous at Sat, 10 Aug 2024 21:06:07 UTC No. 16319130

>>16319117
Shut up nerd.

Anonymous at Sun, 11 Aug 2024 07:39:44 UTC No. 16319607

I got shot with these. They're made from lead. 31 were removed, a further 18 are inside me. 9 are superficial and can be removed but doc recommended to not remove any. Are these gonna get hot from eddy currents in an MRI if I need to get one in the future? Are they going to rust and give me lead poisoning?

Anonymous at Sun, 11 Aug 2024 08:28:34 UTC No. 16319651

>>16319607
There was an episode in House where they put a corpse with bullets in skull in an MRI. It destroyed the machine.

Anonymous at Sun, 11 Aug 2024 08:38:32 UTC No. 16319657

>>16319651
only steel bullets are a problem since they are magnetic, afaik others are all fine. which is also why lead should be fine too.

Anonymous at Sun, 11 Aug 2024 08:47:14 UTC No. 16319664

>>16319657
Why are you so certain it is [math] \textit{pure} [/math] lead?

Anonymous at Sun, 11 Aug 2024 08:50:07 UTC No. 16319669

>>16319664
> lead shot
Why are you so certain it's not?

Anonymous at Sun, 11 Aug 2024 10:36:48 UTC No. 16319736

>>16319657
>only steel bullets are a problem since they are magnetic, afaik others are all fine. which is also why lead should be fine too.
Nope! Nope! Nope!
In an OSCILLATING magnetic field, even non-ferrous metals experience a force.
Recycling centers use this to pull ALL metals out of the shredded garbage stream.

Anonymous at Sun, 11 Aug 2024 12:22:18 UTC No. 16319867

>>16319736
They're in my legs (can't post xrays because they have my reflection in them) I'm worried that they are going to accelerate and perforate my femoral artery in an oscillating magnetic field or atleast get hot, rust and poison me. I am a physics grad working on superconductors and I calculated that something of this nature could happen if I just happened to be working on this.
[math]\mathbf{F} = -\frac{\chi V}{\mu_0} \nabla B^2 for the heat generated in them[/math]
for a 1T magnetic flux density going at 100Hz for a 2mm radius lead ball (resistivity is like 2.0.x10^-7 ohm meters, looked it up ang got this data sheethttps://www.matweb.com/search/DataSheet.aspx?MatGUID=ebd6d2cdfdca4fc285885cc4749c36b1&ckck=1)

I got 1.315 watts which for this amount of lead (1.7g, specific heat capacity is 0.1J/g/k) would mean that it would take it around 80 minutes to get to a 100*C so I can work for like 7 minutes before I hit 60C and tissue damaging temperatures.
didn't bother with forces but you can calculate it with this if you think it's a problem interesting enough to you. I just wanted a few more opinions on this.
[math]\mathbf{F} = -\frac{\chi V}{\mu_0} \nabla B^2 for the force[/math]

Anonymous at Sun, 11 Aug 2024 12:22:52 UTC No. 16319868

>>16319669
Because they usually are alloys, unless of course, anon got shot with a musket gun.

🗑️ Anonymous at Sun, 11 Aug 2024 12:24:12 UTC No. 16319870

>>16319867
fuck
this is the heat equation, that's the force
P = \frac{\pi^2 r^4 f^2 B_0^2}{6 \rho}

Anonymous at Sun, 11 Aug 2024 12:31:03 UTC No. 16319880

>>16319867
fuck
this is the heat equation, that's the force
[math]P = \frac{\pi^2 r^4 f^2 B_0^2}{6 \rho}[/math]
also I'm retarded
I meant seconds. and forgot to remove an earlier bit where I was did the arithmetic in the wrong units.

Anonymous at Sun, 11 Aug 2024 13:05:54 UTC No. 16319903

>>16319868
Doctor said they are made from lead. Meant to be nonlethal to stop protesters.
>>16319880
>math wrong again
Fuck this is embarrassing. I didn't do any arithmetic for the last 3 months... but like for 1.315 watts, a 1.712g lead pellet with specific heat capacity of 0.1004J/g would rise in temperature at a rate of 7.6K/s so I would have like 5.26 seconds for it to get from 20 to 60C. I don't think I'm gonna be working with that strong a field often and even then, it's going to drop off with distance.

Anonymous at Sun, 11 Aug 2024 13:59:51 UTC No. 16319942

>>16319903
fuck I factored out an r^2 when I was deriving it
it's
[math] P = \frac{2 \pi^3 r^5 f^2 B_0^2}{5 \rho}[/math]
So the heat dissipation for a 2mm lead ball in a 1T magnetic field alternating at 100hz would be:
0.0198W which would raise the temperature of a 1.712g (2mm radius) lead ball (0.1004J/g) at a rate of 8.66K/s .
Sorry guys I'm a mess.

Anonymous at Sun, 11 Aug 2024 18:04:57 UTC No. 16320323

>>16301714
What's the name of that low-tech sterilization method when you bring the petri dishes (or whatever) up to about 80°C in a thermostate repeatedly to tire out the germs and shit?
It's on the tip of my tongue, Google is dogshit nowadays, help pls

Anonymous at Sun, 11 Aug 2024 18:45:15 UTC No. 16320374

>>16320323
I managed to remember it, it was tynadllization, not to be confused with the unrelated tyndall effect

Anonymous at Sun, 11 Aug 2024 20:01:11 UTC No. 16320487

>>16319903
He said they are made of lead and not that they are made of only lead.

Anonymous at Sun, 11 Aug 2024 23:21:17 UTC No. 16320655

>>16317234
There's a bunch of fixed point theorems out there, so if your function fits one of them, then it'll work. For a Banach fixed point, to show it's always contractive so you always converge in your domain, all you need is that for all x in your domain, 0 < |g'(x)| <= G < 1 if g(x) = x, where G is the maximum of |g'(x)| on your domain.

Anonymous at Sun, 11 Aug 2024 23:25:30 UTC No. 16320661

is time speeding up?

Anonymous at Mon, 12 Aug 2024 05:04:35 UTC No. 16320941

I got 3 fuses that i removed which are,
-2A 250V
-1A 250V
-200MA(0.2A) 250V

How do i determine what the correct ohm reading is for each one to know which fuse is blown? Is there a formula to follow? 2A and 1A fuse both have a reading of 0.03 ohm while the 200ma(0.2A) has a reading of 01.6 ohm. is a good fuse supposed to read below 0.1 ohm?

Anonymous at Mon, 12 Aug 2024 05:47:11 UTC No. 16320966

>>16320487
Yeah I don't know anything about these aside the fact that they are made of lead at a proportion that someone who knows about them would only mention lead.

Anonymous at Mon, 12 Aug 2024 05:50:38 UTC No. 16320969

>>16320941
A blown fuse will no longer pass current, which is what it was designed to do. You should get a very high resistance.

Anonymous at Mon, 12 Aug 2024 06:08:18 UTC No. 16320986

>>16319903
>>>/k/shotgun

Anonymous at Mon, 12 Aug 2024 07:02:11 UTC No. 16321020

>>16320969
I forgot to note that these were dot fuses or tr5, not sure if its relevant. Should i go by anything reading above 0.1ohm would is considered blown/bad and anything below 0.1ohm is working? Thanks for replying, cant find any info on this

Hate to buy what i dont need considering the price tag on these

Anonymous at Mon, 12 Aug 2024 07:05:58 UTC No. 16321023

>>16321020
just check if they pass current with your multimeter. If it doesn't it's blown.

Anonymous at Mon, 12 Aug 2024 09:10:56 UTC No. 16321078

Does anyone know where I can fold proteins for free online?
I can't run alphafold locally and I could pay for my own server but I want to see how much I can get away with without hosting it on my own cloud compute service.

Anonymous at Mon, 12 Aug 2024 09:50:16 UTC No. 16321103

Guys I just saw Mars and Jupiter. Theyre right next to each other in the sky. Whats a good telescope to get so I can see them better?

Anonymous at Mon, 12 Aug 2024 13:52:07 UTC No. 16321346

>>16320655
You think I don't know that? Idiot.

Anonymous at Mon, 12 Aug 2024 21:08:43 UTC No. 16322135

what's the name of an infinite, never repeating pattern that uses 5 sets of parallel lines where each set is rotated at a different angle?

Anonymous at Mon, 12 Aug 2024 23:44:43 UTC No. 16322402

>>16301721
0*0 = 0 + 0
nonsense * nonsense = nonsense + nonsense

Anonymous at Tue, 13 Aug 2024 05:51:04 UTC No. 16322916

Can anyone help me with this?
I can't prove the all of the conjectures, which are:
[math]
R(n)=R(n-1)+n=1+\sum_{i=1}^{n}i\\
U(n)=2n\\
B(n)=R(n)-U(n)=(1+\sum_{i=1}^ni)-2n
[/math]
And that you need but two colors (this proof seems trivial).
The chapter's on induction, and it's from [math]An\;Introduction\;to\;Proof\;via\;Inquiry\!-\!Based\;Learning[/math], by Dana C. Ernst.
The base cases ([math]n\geq3,\,n\in\mathbb{N}[/math]) are clear and done with a picture, but I'm not sure how to use induction after that for the latter conjectures. For the first one I get something along the lines of [math]R(k+1)=R(k)+(k+1)[/math], which complete with the rest of the proof serves as a full proof to my knowledge. But then for [math]U(n)[/math] I have no idea how to link it to a prior case. I can say that [math]U(k+1)=U(k)+2[/math] but I can't say why this is meaningful or how it's derived from the physical action of drawing the new line.
Likewise, part (c) with [math]B(n)[/math] relies on part (b) so I can't do it.
The last part seems easy; each edge can have only two regions, so we need only two colors. Since there are never curved lines, we never need any additional colors, all cases are covered by a single edge. I'm not sure if this is rigorous enough or not, although it seems clear to me.

Anonymous at Tue, 13 Aug 2024 05:55:23 UTC No. 16322919

>>16322916
Fucking formatting. I'll try again, since I think it was the book title that threw it off:

Can anyone help me with this?
I can't prove the all of the conjectures, which are:
[math]
R(n)=R(n-1)+n=1+\sum_{i=1}^{n}i\\
U(n)=2n\\
B(n)=R(n)-U(n)=(1+\sum_{i=1}^ni)-2n
[/math]
And that you need but two colors (this proof seems trivial).
The chapter's on induction, and it's from An Introduction to Proof via Inquiry-Based Learning, by Dana C. Ernst.
The base cases ([math]n\geq3,\,n\in\mathbb{N}[/math]) are clear and done with a picture, but I'm not sure how to use induction after that for the latter conjectures. For the first one I get something along the lines of [math]R(k+1)=R(k)+(k+1)[/math], which complete with the rest of the proof serves as a full proof to my knowledge. But then for [math]U(n)[/math] I have no idea how to link it to a prior case. I can say that [math]U(k+1)=U(k)+2[/math] but I can't say why this is meaningful or how it's derived from the physical action of drawing the new line.
Likewise, part (c) with [math]B(n)[/math] relies on part (b) so I can't do it.
The last part seems easy; each edge can have only two regions, so we need only two colors. Since there are never curved lines, we never need any additional colors, all cases are covered by a single edge. I'm not sure if this is rigorous enough or not, although it seems clear to me.

Anonymous at Tue, 13 Aug 2024 06:38:37 UTC No. 16322954

>>16322919
I don’t understand your last proof. «each edge can have only two regions, so we need only two colors» is false: ever heard of the 4 colours theorem? If not picture a triangle with lines that go to infinity leaving each vertex. It makes 4 regions that all touch each other.

As for your conjectures, they seem right but you need to prove them. The only thing you need to prove is the inductive formula: when you add the $n$th line, why does it create $n$ new regions, $2$ of which are unbounded?

Finally, it is a quite well-known fact that $\sum_{i=1}^n i = \frac{n(n+1)}{2}$. You can picture putting the consecutive numbers in a triangle which makes half the $n \times (n+1)$ rectangle.

Anonymous at Tue, 13 Aug 2024 07:31:34 UTC No. 16322991

>>16321078
doesn't jewgle or some megacorp offer cloud compute for free?

hazardo at Tue, 13 Aug 2024 08:16:06 UTC No. 16323049

if you made an important scientific discovery but were just some regular guy where would you post it or who would you want to contact/discuss it with?

Anonymous at Tue, 13 Aug 2024 08:37:11 UTC No. 16323064

>>16323049
Send a polite email to researchers in the field. I know at least in math/theoretical CS they tend to be very open, but you can still get unlucky and get flagged as spam. I guess depending where you are you can find a way to actually meet one by going to some university (in France there exists some uni lessons that are open to the public).

However, do keep in mind that some regular guy making a true scientific discovery is extremely unlikely.

Anonymous at Tue, 13 Aug 2024 09:53:06 UTC No. 16323154

If the brain's a heckin plastic organ, why can't IQ be improoved? If it's supposedly as adaptable as the muscles, why does intensive training repeatedly fail to raise it permanently?

Anonymous at Tue, 13 Aug 2024 10:12:45 UTC No. 16323178

>>16319607
you DO KNOW that a MRI incorporates a metal detector exactly for this reason... I mean, fuck, it IS one if you set the power low (which is what they do.) The damn thing wont even turn on if you are unsafe for it to image. House skipped that bit because it was bad for TV.

Anonymous at Tue, 13 Aug 2024 16:25:14 UTC No. 16323572

>>16322954
As the problem describes corners don't matter, only edges. Here's an example, with four lines. If you could provide a counter example I'd be interested to see it.
As for the rest I'll take a look more in depth later when I've the time, but the biggest thing is I can't answer
> when you add the $n$th line, why does it create $n$ new regions, $2$ of which are unbounded?
The conjectures I found by just drawing the first three iterations, counting, and noticing the patterns. I have no intuition as to why they exist, so I need to find an argument for it, which I suspect your last line helps me with.

Anonymous at Tue, 13 Aug 2024 20:49:03 UTC No. 16324032

>>16323178
Explain all the MRI accidents then.

Anonymous at Wed, 14 Aug 2024 00:12:53 UTC No. 16324317

engineering mathematics is embarrassing. it asks of the reader to become an algorithm monkey. I still don't understand what's the point of taking a DE course when most DEs are unsolvable analytically.
I wish I spent the time learning analysis.

Anonymous at Wed, 14 Aug 2024 00:13:35 UTC No. 16324319

>>16323154
IQ can be improved. You have no evidence on the contrary

Anonymous at Wed, 14 Aug 2024 00:25:32 UTC No. 16324346

>>16324319
>Prove me wrong! So there!
Doesn't work that way, Billy.

Anonymous at Wed, 14 Aug 2024 00:32:06 UTC No. 16324356

>>16324317
>I still don't understand what's the point of taking a DE course
Why would there be a point? It's just a monkey trap. They want people to understand the theory, but that's too difficult so they dumb it down making it useless, instead of letting go.
It's very common when you want X but can't have it to end up with a fake pointless thing that has an aura of X.

Anonymous at Wed, 14 Aug 2024 01:04:42 UTC No. 16324399

>>16323154
but you can?

Anonymous at Wed, 14 Aug 2024 02:26:08 UTC No. 16324469

>>16324317
>I still don't understand what's the point of taking a DE course
it gives you a bit more understanding of the aforementioned algorithms that youre going to have to use. have you taken a control theory course?

Anonymous at Wed, 14 Aug 2024 02:32:54 UTC No. 16324476

>>16324317
>when most DEs are unsolvable analytically
i think caring about the solvability is a pretty "algorithm monkey" thing to say. i took a multivariate calculus course in school. i couldnt solve a path integral or surface integral without looking it up, but i *know* what path and surface integrals are, and thats by far way more important when it comes to applying those concepts in physics.

Anonymous at Wed, 14 Aug 2024 15:14:26 UTC No. 16325129

If you cut a pizza by four straight lines into 11 pieces, is it possible to make all the pieces the same size?

Anonymous at Wed, 14 Aug 2024 15:20:47 UTC No. 16325147

>>16324317
Read Arnol'd's book on ODEs and Olver's on PDEs (specifically also his book on lie groups and DEs). This will give you a strong geometric understanding of DEs

Anonymous at Wed, 14 Aug 2024 15:26:09 UTC No. 16325154

>>16324476
this. It's far more important to develop an intuition for the geometry of DEs and how to interpret them

Anonymous at Wed, 14 Aug 2024 15:29:39 UTC No. 16325164

>>16322402
Read Gel'fand

Anonymous at Wed, 14 Aug 2024 15:40:19 UTC No. 16325179

>>16325129
is there only one way to cut a pizza into 11 slices with 4 cuts?

Anonymous at Wed, 14 Aug 2024 16:12:03 UTC No. 16325230

>>16325179
Basically the requirement is that every line intersects with every line. Otherwise you don't get 11 pieces.

Anonymous at Wed, 14 Aug 2024 16:53:51 UTC No. 16325292

>>16325129
An interesting follow up question: if you cut the circle into pieces by N lines such that every line always intersects every other line (this is possible for any N), what is the maximum number of pieces with equal area that you can make for any integer N? For example, for N=4 five pieces seems to be possible, maybe six.

Anonymous at Wed, 14 Aug 2024 17:57:15 UTC No. 16325415

If A implies B, and C implies D, how I infer A or C implies B or D using zeroth order logic.

Anonymous at Wed, 14 Aug 2024 18:20:33 UTC No. 16325474

>>16325415
Exhaustively.

Anonymous at Thu, 15 Aug 2024 05:45:17 UTC No. 16326358

>>16325474
What is that?

Anonymous at Thu, 15 Aug 2024 06:35:26 UTC No. 16326469

What does completeness mean in logic?
I have seen two definitions: one is that whenever [math] \Gamma \vDash \phi [/math], then [math] \Gamma \vdash \phi [/math], and the other is that for every [math] \phi [/math], [math] \Gamma \vdash \phi [/math] or [math] \Gamma \vdash \neg \phi [/math].

Anonymous at Thu, 15 Aug 2024 06:47:23 UTC No. 16326494

Why shouldn't I remove my ability to speak? It would make life easier

Anonymous at Thu, 15 Aug 2024 12:47:30 UTC No. 16326830

>>16301714
How do I make 1000mg of potassium citrate? How much potassium carbonate and citric acid do I use?

Anonymous at Thu, 15 Aug 2024 20:10:18 UTC No. 16327836

>>16326494
because you can just pretend you lost your ability to speak
>>16324476
What intuition is there to DEs? Aside from modeling they were just integration and algebra checks.
>>16324469
should I? I'm just self-learning physics
>>16325147
I'll check them out

Anonymous at Thu, 15 Aug 2024 20:37:43 UTC No. 16327888

>>16327836
>What intuition is there to DEs?
as far as ODEs go, solutions that are linear combinations of [math]e^{ikx}[/math] are about 99% of the intuition youre gonna need. the solutions have transient components and steady-state components, they are asymptotic or unbounded, they can be real (overdamped) or complex (underdamped), and a bunch of other shit. if a particular solution has a sinusoidal component, even if you dont actually bother solving for said solution, *even if the solution is nonelementary*, if you understand exactly why sin waves show up in DE solutions, it helps you get an idea of whats going on under the hood. a lot of things in math/science are like that. Fourier series are cool, although i could not prove to you that sinusoids form a basis for periodic functions (and in fact, neither could Fourier), but thats not really the important part.
>should I? I'm just self-learning physics
control theory is the most useful thing you can learn in math, but if youre just learning for fun and dont actually plan on building things then you might not care about usefulness.

Anonymous at Thu, 15 Aug 2024 21:36:53 UTC No. 16328016

>>16327836
also
>I'm just self-learning physics
if youre self-learning physics, can i ask why you referred to it as "engineering mathematics"? what book are you reading?

Anonymous at Thu, 15 Aug 2024 22:41:25 UTC No. 16328112

>>16328016
zill's advanced engineering mathematics

Anonymous at Thu, 15 Aug 2024 22:46:54 UTC No. 16328119

>>16327888
I'll never make something useful, I only solve problems. If control theory is fun I'll learn it seriously

Anonymous at Thu, 15 Aug 2024 23:01:26 UTC No. 16328140

>>16328119
>If control theory is fun I'll learn it seriously
you can give it a look. youll need uhhhh lemme think, ODEs and linear algebra i believe are the only prerequisites.

Anonymous at Fri, 16 Aug 2024 07:28:18 UTC No. 16328660

I'm curious why /sci/ seems to have mostly avoided the new round of monkeypox shilling, perhaps we are less infiltrated by /pol/ than I thought

Anonymous at Fri, 16 Aug 2024 09:33:04 UTC No. 16328748

Why was the Wright brothers demonstrating flight such a big deal and why were people so skeptical of it when we already had Zeppelins back then? We were already capable of flying it was just about coming up with different methods for it.

Anonymous at Fri, 16 Aug 2024 09:51:56 UTC No. 16328764

>>16328748
Because it was the first sustained, controlled, powered, heavier-than-air, manned flight.

Anonymous at Fri, 16 Aug 2024 13:36:46 UTC No. 16328950

What's the scientific answer to why one feels absolutely awful if you jerk off too soon after you ate?

Anonymous at Fri, 16 Aug 2024 15:33:19 UTC No. 16329118

little confused about lidar and radar. technically they both use different forms of light. But lidar uses lasers, radar doesnt. However why wouldnt you get the same affect if you were to focus radar into a single beam?

Anonymous at Fri, 16 Aug 2024 15:38:19 UTC No. 16329132

I developed a genius original idea that I'll become immortal by daytrading futures. Here's the idea: market goes up on average, so if I buy every morning and sell every evening, I'll win on the long term.

Spoonfeed me a book about statistics and risk management in these circumstances. I know math and statistics so I'll be fine. I don't care about "trading analysis" or whatever it is fags call those faggy lines they draw over charts to predict the future.

Anonymous at Fri, 16 Aug 2024 15:55:53 UTC No. 16329168

>>16329118
You could but since radar uses much longer wavelengths the resolution if the images would be awful.

Anonymous at Fri, 16 Aug 2024 15:59:19 UTC No. 16329173

>>16329132
https://en.wikipedia.org/wiki/Black%E2%80%93Scholes_equation

Anonymous at Fri, 16 Aug 2024 16:00:29 UTC No. 16329175

>>16329168
i dont understand/have the knowledge as to why longer wavelengths would be an issue.

Anonymous at Fri, 16 Aug 2024 16:22:55 UTC No. 16329208

>>16329175
That's a general limitation of any kind of optics or imaging system. The smallest size or 'pixel' that can be resolved is limited by the wavelength of the light used.

🗑️ Anonymous at Fri, 16 Aug 2024 18:18:55 UTC No. 16329341

>in picrelated there's the curve y = sqrt(x) and a unit circle
>what are the coordinates of the center of the circle if the circle intersects the x-axis in one point and the curve y=sqrt(x) also in one point?

Anonymous at Fri, 16 Aug 2024 18:20:15 UTC No. 16329344

>in picrelated there's the curve y = sqrt(x) and a unit circle
>what are the coordinates of the center of the circle if the circle intersects the x-axis in one point and the curve y=sqrt(x) also in one point?

Anonymous at Fri, 16 Aug 2024 18:32:49 UTC No. 16329358

>>16301714
>>>/r9k/ tourist here
I don't wanna stay in that retard containment zone cause I almost got laid and BTFO'd those 90 iq retards. Next time I will not fail nor listen to their pathetic blackpill.
inb4 go to /fit/

Hypothetically speaking, or rather I'm asking... for a friend... yeah...

Would it be possible to increase my penis size by changing something in my diet? Assuming I go on a strict nofap for 12 months to boost my Androgen Receptivity, take Creatine supps and ZMA stack. I am 27 years old and worried that it might be a bit too late for me.

I got info from a youtuber that Sorghum grain diet increases DHT and also happens to increase the sexual prowess.

Totally not insecure, but adding a few cm would totally be great. It's never enough.

Anonymous at Fri, 16 Aug 2024 18:55:43 UTC No. 16329382

>>16329344
The system
y^2 = x
(x - a)^2 + (y - 1)^2 = 1
must have a double root.

>First eliminate x from the system
(y^2 - a)^2 + (y - 1)^2 = 1
y^4 + (1 - 2a) y^2 - 2y + a^2 = 0
>Set the discriminant equal to 0
256 a^4 - 1152 a^3 + 400 a^2 + 96 a - 448 = 0
>Solve with quartic formula for a and take the positive real solution
a = 4.124...

Anonymous at Fri, 16 Aug 2024 22:06:10 UTC No. 16329621

What happens if you integrate without the differential?

Anonymous at Fri, 16 Aug 2024 22:33:26 UTC No. 16329652

>>16329358
We mostly have IQs of around 90 here too. It's 4chan.

Anonymous at Fri, 16 Aug 2024 22:40:20 UTC No. 16329658

how is a minimal generating set different from a basis?

Anonymous at Fri, 16 Aug 2024 23:15:51 UTC No. 16329683

What would happen in this situation:
You have an airtight chamber filled with some gas that isn't oxygen, let's just say nitrogen. In the chamber you have two pieces of wood and you have some method of causing massive amounts of friction between the wood, generating far more heat than what would be required to ignite.
What would happen to the wood if it became extremely hot without igniting? Would it just break down into dust? Would it melt?

Anonymous at Fri, 16 Aug 2024 23:16:58 UTC No. 16329684

>>16329621
a differential will be generated to cancel out the fraction

Anonymous at Sat, 17 Aug 2024 00:26:21 UTC No. 16329783

>>16329683
https://en.wikipedia.org/wiki/Activated_carbon#Production

Anonymous at Sat, 17 Aug 2024 18:51:49 UTC No. 16330747

I don't get this, shouldn't [math]\mathcal{D}^n_{\mathbb{R}}(\mathbb{R})[/math] be a subspace of [math]\mathcal{D}_{\mathbb{R}}(\mathbb{R})[/math] and not the other way around? Also, by the definition in the image shouldn't they be the exact same set? Is the definition wrong or am I missing something?

Anonymous at Sat, 17 Aug 2024 18:59:00 UTC No. 16330751

>>16330747
The definition is essentially saying that [math]\mathcal D(\mathbb R) = \bigcap_n \mathcal D^n(\mathbb R)[/math].
There's certainly functions that are [math]n[/math]-times differentiable, but not [math]n+1[/math]-times (or infinitely).
For example [math]|x|,x|x|,x^2|x|,...[/math].

Anonymous at Sat, 17 Aug 2024 19:08:40 UTC No. 16330760

>>16330751
Thank you, I understand now how they're different sets, but I still don't understand why [math][math]\mathcal{D}^n_{\mathbb{R}}(\mathbb{R})[/math] isn't a subspace of [math]\mathcal{D}_{\mathbb{R}}(\mathbb{R})[/math].

Anonymous at Sat, 17 Aug 2024 19:22:03 UTC No. 16330767

>>16330760
It's not even a subset of [math]\mathcal D[/math], which should be the first requirement, before you even look at a linear structure.

Anonymous at Sat, 17 Aug 2024 20:26:39 UTC No. 16330836

>>16329382
That's a pretty complicated x-coordinate but it works

https://www.desmos.com/calculator/ionw8odtk1

Anonymous at Sat, 17 Aug 2024 20:31:06 UTC No. 16330838

>>16330836
>pretty complicated
its the solution to a quartic, it can literally be written using only addition, mulitplication, and integer roots. all things considered its pretty tame.

Anonymous at Sat, 17 Aug 2024 22:12:24 UTC No. 16330943

First time reading about the slug unit.
I like american books, but the unit system is jarring.

Anonymous at Sun, 18 Aug 2024 06:16:47 UTC No. 16331256

is there theoretically a way to generate energy from nuclear reactions directly instead of nuclear reactors having to boil water? how efficient is using nuclear reactions to create steam for the purpose of generating energy? surely there's a better way, right?

Anonymous at Sun, 18 Aug 2024 06:39:50 UTC No. 16331267

>>16331256
Not really. Most of the energy from the fission reaction ends up as heat - you lose some neutrinos but that's essentially it. So then you need some kind of heat engine to turn that into usable energy, which for our society essentially means electricity. We have been using steam to do work for over a century; the technology is simple to build, stable, and incredibly mature. Modern industrial steam turbines approach close to 90% efficiency.

🗑️ Anonymous at Sun, 18 Aug 2024 09:16:59 UTC No. 16331370

>>16330838
I tried solving the x-coordinate of the intersection point between the circle and sqrt(x) and I got this madness. And here the "a" needs to be replaced by x-coordinate of the circle making it many times more messy. This would be a fun problem to solve in an exam

Anonymous at Sun, 18 Aug 2024 20:46:29 UTC No. 16331934

Is TikZ worth learning or do you guys just use something else for drawing on [math]\LaTeX[/math]?

Anonymous at Sun, 18 Aug 2024 21:23:58 UTC No. 16331964

This shit is fucking magic to me, can someone give me a paragraph or so breakdown? I've tried reading into it and it's just so confusing, am I missing something? volts, amps, current, oh my

Anonymous at Mon, 19 Aug 2024 03:18:33 UTC No. 16332261

>>16331964

Anonymous at Mon, 19 Aug 2024 15:35:04 UTC No. 16332753

Why Gelfand writes down divisions this way (dividend on the right, divisor on the left, quotient at the top)? Is this a common way of writing it down in Russia or whatever?

Anonymous at Mon, 19 Aug 2024 15:36:12 UTC No. 16332759

>>16332753
This is a common way of writing across the world.

Anonymous at Mon, 19 Aug 2024 15:39:14 UTC No. 16332764

>>16332759
Holy shit, I've never realized other people did divisions like that. I just searched "division" and they all look like Gelfand's.
Picrel is the way I was taught.

Anonymous at Mon, 19 Aug 2024 16:18:26 UTC No. 16332823

>>16314879
1 -> 3 (lhs), 3 -> 4 (rhs), so 1 -> 4
4 -> 3 (rhs)
3 -> 1 (lhs), 1 -> 2 (rhs), so 3 -> 2
therefore this permutation is (1, 4, 3, 2)

Anonymous at Mon, 19 Aug 2024 17:08:43 UTC No. 16332941

>>16332764
never seen this before in my life. what cunt?

Anonymous at Mon, 19 Aug 2024 17:15:04 UTC No. 16332965

>>16332941
Bwozil.

Anonymous at Mon, 19 Aug 2024 17:15:39 UTC No. 16332968

>>16332965
Yes she is

Anonymous at Mon, 19 Aug 2024 17:15:48 UTC No. 16332969

>>16332965
egh, gross.

Anonymous at Mon, 19 Aug 2024 17:44:40 UTC No. 16333069

How important is the choice of textbooks for undergraduate math?
Can I use whatever I want as long as I follow the curriculum even if the textbooks the professors use are different?

Anonymous at Mon, 19 Aug 2024 17:47:21 UTC No. 16333078

>>16331964
Little particles travel between atoms inside a wire?

Anonymous at Mon, 19 Aug 2024 18:01:53 UTC No. 16333116

Our fingertips are very sensitive. Why is it that when you glide your fingers very slowly over something with a texture you can feel the texture acutely, but when you stop moving your fingers and simply hold the thing, you don't feel the texture nearly as much? Is this a limitation of our skin, our brains, or both?
My assumption is that in all ways our brains are better at identifying changes over time than picking out details that are standing still. For the same reason, it's easier to find a deer in a forest if it's moving than if it's standing still for a really long time

Anonymous at Mon, 19 Aug 2024 18:15:48 UTC No. 16333155

I know perpetual motion is impossible but I have been thinking about some impossible machines that I can't figure out where they fail at. Here is a link of some drawings and explanations so you understand better.
https://imgur.com/a/zfExkcG

Anonymous at Mon, 19 Aug 2024 18:25:34 UTC No. 16333178

>>16333116
For the same reason why simply touching a knife is different than moving it across your finger

Anonymous at Mon, 19 Aug 2024 18:27:35 UTC No. 16333185

>>16333155
assuming 100% efficiencies here.
>1
the energy it takes to pump the water back into the bottom of the tower is exactly equal to the potential energy of the water while its at the top. different fluids and tower height will not fix this.
>2
subtle. the balloons is at H_0 and compresses air to some higher pressure, causing it to fall to H_1. the amount of energy it take to compress the air will be exactly equal to the potential difference between H_0 and H_1. this one is interesting because the potential difference is proportional to the pressure squared (twice as much air will weigh twice as much and fall twice as fall), implying that the energy required to compress is also proportional to the pressure squared, which is true (assuming the tank is constant volume, if you double the pressure, you need also need double the molecules inside the tank).

Anonymous at Mon, 19 Aug 2024 18:38:02 UTC No. 16333206

>>16333185
Okay I understand the tower one.But with the second what makes it impossible so I can't just wait until reaching maximum height then compress the air,wouldn't the potential difference be the same but the fall much greater?

Anonymous at Mon, 19 Aug 2024 18:39:56 UTC No. 16333208

>>16333206
it gets harder to compress the air the higher you go.

Anonymous at Mon, 19 Aug 2024 18:55:03 UTC No. 16333234

>>16333155
i actually had an idea for a free energy machine similar to your second one, but instead of air it was in a big vat of incompressible fluid lighter than water (oil maybe), it used a water bladder instead of compressing air, and the "balloon" hydrolyzed the water once it got to the bottom. i suspect the issue with it is that hydrolysis takes more energy at higher ambient pressures but i never really looked into it.

Anonymous at Mon, 19 Aug 2024 20:48:27 UTC No. 16333434

>>16332261
Thanks anon this helped

Anonymous at Mon, 19 Aug 2024 22:08:20 UTC No. 16333553

What makes quantum entanglement special?

Lets say we have two balls, one red and one blue. We put them into two separate boxes, mix them, and sends one off for 10 years in a spaceship.

Once we open the box we kept, we'll know the color of the other ball. That's just logical. Why is quantum entanglement different, and what is its use case?

To me it just sounds like philosophical masturbation.

captcha: dr rj

Anonymous at Mon, 19 Aug 2024 22:25:12 UTC No. 16333583

Another perpetual machine I can't figure out the problem.
Supposing that is made from light material.Also the numbers are random.

https://imgur.com/a/uaofcnD

Anonymous at Mon, 19 Aug 2024 22:41:10 UTC No. 16333607

>>16333553
Because while entangled the two balls behave as a single quantum object with its own unique properties. Acting on that entangled state gives you different results than acting on the two balls seperately. So yes, it is a form of correlation but one that is intrinsically quantum in nature and that gives result different to a red/blue ball in each box. As for use cases, quantum encryption and quantum computing are the two main areas.

Anonymous at Mon, 19 Aug 2024 22:47:37 UTC No. 16333621

>>16333553
you can alter the results of an experiment by measuring the properties of a particle. consider the double slit experiment. if the wave function of particle is spread between the two slits, it will interfere with itself as it travels to the detector behind the slit, leading to an interference pattern (c in pic related). however, if you measure the position of the particle right before it goes through one of the slits, the wave function is no longer spread between the two and it wont interfere with itself, so no interference pattern (b in pic related). the theories as to why the wave function does this are as numerous as they as unfalsifiable. the Copenhagen interpretation says that the wave function "collapses" when you make the measurement. the many worlds interpretation says that you become entangled with the particle once you measure it, so the only possible outcomes you can witness are the ones that correlate with your measurement.
but its easy to think that the real reason this happens is specifically *because* you measured the particle, and by measuring it you had to interact with it, hitting it with photons or whatever, thereby altering the course of its trajectory yourself, and the actually "measurement" had nothing to do with it, it was just you fucking with it. the problem with that idea is that this experiment is doable with entangled pairs. you measure one particle, you indirectly measure the other. you didnt fuck with the other particle, you didnt change its trajectory or spin or whatever, and yet the fact that you measured its entangled pair causes it to behave differently. the "spooky action at a distance" isnt the actual measurement, its that you can change how the wave function of the particle evolves, influencing future measurements on the particle.

Anonymous at Tue, 20 Aug 2024 01:11:47 UTC No. 16333771

Could charge parity time symmetry suggest that all the antimatter generated in the big bang just created a mirrored antimatter universe going backwards in time? That there is another exactly dual universe that exists 26 billion years "away" from now?

Anonymous at Tue, 20 Aug 2024 02:03:47 UTC No. 16333818

>>16333553

That sounds like hidden-variable theory.
Already been deboonked by the Bell experiment

Anonymous at Tue, 20 Aug 2024 02:28:32 UTC No. 16333843

>>16331964

Electricity is a consequence of the laws of electromagnetism. EM is just a very simple set of rules that say that all fundamental particles in the universe can be positive, negative or neutral. Like charges repel, different charges attract. This set of rules governs almost everything that happens in the universe, from light, heat, chemical reactions, formation of atoms, formation of molecules, solid object physics etc

Anyway, EM forces negative electrons together with positive nuclei, creating atoms and molecules, and cancelling out the charge, so our world has an overall neutral charge. But it isn't that hard to knock electrons out of atoms and create pockets of charge imbalance again. And just like how differences in air pressure create wind and differences in water pressure create eddies and currents, differences in charge pressure create eddies and currents called electricity. You can create the imbalance through chemical reactions (electrochemistry like batteries and potato clocks), creating continuous electromagnetic waves by spinning a magnet (Faradays law like turbine generators) or simply rubbing stuff together (the triboelectric effect, like lightning or the old "rubbing a plastic binder on your hair" trick)

Anonymous at Tue, 20 Aug 2024 03:01:15 UTC No. 16333866

>>16333818
i just throw out the free will hypothesis

Anonymous at Tue, 20 Aug 2024 06:46:15 UTC No. 16334071

>>16333069
It's not that important but generally speaking, undergrad texts usually overemphasize analysis (while doing near to no geometry or algebra). Another thing is that graduate texts often have very little to no prerequisites which is why you should just read them anyway

Anonymous at Tue, 20 Aug 2024 08:07:19 UTC No. 16334156

>>16333621
Is that a ChatGPT answer? Nothing to do with the double-slit experiment is related to entanglement.

Anonymous at Tue, 20 Aug 2024 15:45:36 UTC No. 16334661

>>16334156
it was just an example demonstrating why quantum entanglement is a bit more nuanced than two balls in a box.
https://en.wikipedia.org/w/index.php?title=Delayed-choice_quantum_eraser

Anonymous at Tue, 20 Aug 2024 17:12:03 UTC No. 16334809

>>16334661
It was a god awful answer that did nothing to answer the original question.

Anonymous at Tue, 20 Aug 2024 17:22:05 UTC No. 16334830

>>16334809
whats so bad about it?
>"i dont understand whats so special about entanglement, if i put two balls in some boxes then i can know whats in the other box 'faster than light', but that doesnt seem interesting."
>"well actually if the two balls are entangled you can affect how the other ball behaves during measurements, heres a real-world experiment thats proven this phenomenon."
i sure hope you arent this guy >>16333607