Any recent news involving quantum computing?

>>16945820
Anyone?

Holy kek this /sqt/ is on life support

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>>16946435
Don't worry, it'll be up and going right after spring break.

Can someone do my homework, it's a geogebra question thing making a construction for the Riemann integrals, thanks y'all <3

>>16947913
ask ai

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>>16947913
If you can construct the diagram like this, that could work out alright in Geogebra

>>16949655
no...

>>16949655
>muh ai
kys

has qc surpassed the 40 qubit number or whatever it was 5 years ago? I mean actual qubits that can be entangled and used, not some meme marketing number.

>>16953175
ask ai

>>16953180
ai is bought and paid for by qc companies and their not useful qubit counts

https://www.youtube.com/watch?v=JtSYeftGUGE
Did he use LLM to rewrite his script? The style just gives me LLM vibe.

>>16947913
>it's a geogebra question
https://www.geogebra.org/

>>16956910
I don't think so because at 5:18 mark, he used ChatGPT to "cross-reference with the devil"

What is the most elegant "triangle inequality check"?

>>16957721
s = (a + b + c)/2
If (s – a)*(s – b)*(s – c) > 0,
then the side lengths form a triangle.
Otherwise they don't.

>>16957721
Basically the same as >>16957863, but just check if (a+b-c)(a-b+c)(-a+b+c) > 0, cause triangle equality says all 3 terms are positive and it isn't possible for 2 to be negative. No need to consider area

>>16944314
I want to make a borax mixture, as explained here: https://alsnetbiz.com/homeimprovement/homemade.html (the "equivalent to Bora-Care". instructions under "Prepare the concentrate")
I plan on using propylene glycol, and heating the mix in an electric kettle made of glass and/or a ceramic pot.
is this propylene glycol as safe as the instructions say? is the borates mix safe enough to reuse the pot, or should I only keep it for chemical stuff in the future?

>>16958715
>propylene glycol
they put it in food and cosmedic products, and is a laxative

>>16958904
yeah, that's why I chose to use it instead of the ethylene.
still, I want to be as cautious as possible. that's why I'm asking.
what about the borax and boric acid? also wonder about the gases. at 260°F I can imagine some nasty things might form and fly from the mix?

>>16958170
>(a+b-c)(a-b+c)(-a+b+c)
= (a + b – c)*(a + c – b)*(b + c – a)
= (a + b + c – 2*c)*(a + b + c – 2*b)*(a + b + c – 2*a)
= (2*s – 2*c)*(2*s – 2*b)*(2*s – 2*a)
= 2*(s – c)*2*(s – b)*2*(s – a)
= 2^3*(s – a)*(s – b)*(s – c)

>>16958170
>(a+b-c)(a-b+c)(-a+b+c)
= (a + b – c)*(a + c – b)*(b + c – a)
= (a + b + c – 2*c)*(a + b + c – 2*b)*(a + b + c – 2*a)
= (2*s – 2*c)*(2*s – 2*b)*(2*s – 2*a)
= 2*(s – c)*2*(s – b)*2*(s – a)
= 2^3*(s – a)*(s – b)*(s – c)

>>16959149
This post was invisible for more than one hour. That's why I accidentally posted it a second time. It only became visible after I posted it the second time.

>>16944314
>13 days
>25 posts
JUST

>>16958918
>wonder about the gases
No harmful gases should come off, borates will not decompose from the heat and they wont react with anything in your mixture.

Dont reuse the pot for making food borates are toxic to eat keep that pot for chemistry/junk

>Le particle is in a bunch of places at once until it's measured, then it's in one place
So how do they know that it was in a bunch of places at once before they measured it? Nobody ever actually describes the experiment, they just show you the alleged conclusion and go "ooh, spooky science!"

>>16960315
Because they perform experiments. That was what the 2022 Nobel Prize was for.

It's also what the Dual Slit experiment demonstrates, which is why it is brought up all the time. It's the simplest experiment that shows the particle can't be in a single place before it is measured.

>>16960337
The claim of self-interference is not reducible to an empirically verifiable sequence. The label of self-interference is hyper specified to particular experimental arrangements not having anything to do with self-interference of one or more underlying elements.
Consider an experiment that sets out to demonstrate a claim about an element interacting with itself. There is no means to isolate the element from the experimental apparatus or any of its partial interactions without reflexively destroying the claim of self.
As such, the inductive chain does not exist and the conclusion about underlying particles or emissions is confabulation.
A further paradox arises when trying to minimally fit the frame to the apparatus and experimental parameters. We don't even get to say a self-cycle is occurring by the same logic before.

>>16960404
> when AI halucinates

What are the best books from a beginner's perspective for embedded systems and aerospace engineering, particularly astronautics?

So, if you push a long thin rod into a wormhole with a throat diameter smaller than its length sideways, what happens? Does the rod bend around the curved spacetime of the wormhole until it hits itself?

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What are the three acute angles equal to (in radians)?
Hints:

h = [irrelevant]
S(r) = {(x, y): |x| < r, |y – h/2| < Sqrt[r^2 – x^2] + h/2}

region 1 = S(7)
facecolor = (G + C)/2

region 2 = S(5)
facecolor = G = green

region 3 = S(3)
facecolor = (G + Y)/2

region 4 = [irrelevant]
facecolor = G

region 5 = {(x, y): |x| < 1, |y + 9/2| < h + 9/2}
facecolor = Y = yellow

region 6 = [irrelevant]
facecolor = C = cyan

I have to design and complete a research project/paper (for Geoscience) for my major. If I'm understanding, I'll have eight weeks for design and prep, and eight weeks to complete it, with some time in between the two courses.
How do I...do a research project? I swear half the time I Just try to come up with something that sounds like I can get credit for it and toss it at the wall but that's probably not a good idea for a final level assignment.

>>16961592
The kinda goofy, but overall answer to this is "follow the scientific method":
1. Pick a phenomenon or a problem (maybe even one that seems obvious -- a good jumping off place is "extra credit problems you may have had on tests," because that's how profs often talk about their own real research.)
2. Make a hypothesis about a solution to that problem -- what do you need to test to prove if it's true or if a technique is "good"? What assumptions does that require?
3. Hit the literature & find papers and books around the topic. Use the keywords from 2. to dig -- to start, you really should use actual library tools or your textbooks to find papers etc., but Google Scholar also works. (Your school probably has a research guide for a particular field like this:
https://libraries.etsu.edu/research/guides/geosciences/methods)
4. You'll probably end up getting an answer to some of your idea through the literature, but there's probably a gap or someone not doing a good job explaining why or having shitty code or whatever. Bingo, there's your Thing To Do.
5. Iterate

There's also a textbook, "Research Methods in Geography" that you can probably find on libgen or by searching around.

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>>16961027

y = –Sqrt[r^2 – x^2]
Tan[θ] = dy/dx = –x/y
α = π/2 – θ = ArcSec[Abs[r]/x]

If r > 0 and x = 1 (which is the case),
then α = ArcSec[r].

Thus the acute angles are
ArcSec[3], ArcSec[5], and ArcSec[7]
from top to bottom.

>>16961610
Thank you. I found that book. It was free for whatever reason, praise be to abdul or whoever uploaded it.

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Solve Fermi’s paradox from a biologist’s point of view.

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>>16961027
>G = green
>Y = yellow
>C = cyan
That one is based on the dark blue one, on the wall.

>>16962475
Get out there and take tissue samples from the few planets we can land on, nerd.

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Consider the trumpet formed by rotating the curve around e^{-ax}. A wire coils around it at some particular angle starting from x = 0. It makes an angle theta at the meridian of x = 0. What is its length at x = t?

>>16963753
I meant rotating the curve of e^-ax around x axis.

>>16963753
> A wire coils around it at some particular angle starting from x = 0.
> It makes an angle theta at the meridian of x = 0.
> What is its length at x = t?
Huh?? I have no idea what you are even trying to describe.

Maybe try a better picture?

>>16963753
Before you post a problem, you should ask yourself, "Is the problem unique?" Is the problem constructed in a unique way (or more interestingly, is the solution constant over some space)?

Do you really think boundary conditions are enough for this problem to hold a unique solution? Or do you think that the solution is path independent and requires no further info?

If you're asking for homework, radial coordinates have orthogonal tangent vectors for the differential, so the length element is simply [math] \sqrt{ r^2 \dot\theta^2 + (1+ \tfrac{dz}{dr}^2)\ \dot{r}^2 } ds [/math], when parametrized by length s

there used to be this google drive full of math books, do you guys know if it's back up/been reuploaded?

>>16963916
>Do you really think boundary conditions are enough for this problem to hold a unique solution?
No, I forgot to mention the angle is supposed to be constant.

>>16964469
The problem is easy. The differential tangent basis vector to the tangent space at a point for the angular coordinate phi is always tangent and parallel to the surface parallels, and the same for the radial tangent vector to the meridian, so constant angle to the meridian also is constant angle to the parallel, and parametrizing by arc length means the arc tangent vector on the surface will have constant coordinates [math] (dr/ds, d\phi/ds) = ( \tfrac{ \cos\theta) }{ \sqrt{ 1 + (dz/dr)^2 } } , \sin\theta/r ) [/math] for each tangent space. Since z(r) is a function, change the arc length line element from ds to dr (not d\phi), and plug in [math] \tfrac{ d\phi }{ dr } [/math], and plug the integral into wolfram alpha

>>16963916
change the \dot\theta to \dot\phi, since you said theta was the constant

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Little plant seeds should be sown at least 1 cm apart from each other to be sown properly. You have a circular pot whose diameter is one meter. You throw the seeds into the pot randomly. Despite throwing them in there like that, you want there to be at least 70% probability that all the seeds are sown properly (no two seeds are closer than 1 cm apart).

What is the maximum number of seeds that you can sow?

>>16965305
ask AI

Does the nature of constantly needing to find 'novel' research subjects essentially create a race to be as esoteric as possible as you try to write your five or six publications a year?

>>16965305
It's just the circle packing problem but for 70% of the seeds, and for the other 30% you place them all in a single point

>>16965305
If I wanted at least 70% probability of success, I'd not throw them randomly like a giant fag.

What is the maximum number of faces a solid can have whose faces are polygons that are all identical in shape and size?

>>16966476
You question is slightly ambiguous so it's either one of:
-- Regular polygon faces (Platonic solid) 20 (icosahedron)
-- Any congruent polygon faces 120 (disdyakis triacontahedron)

>>16966596
I see how that works. Icosahedron has 20 equilateral triangles as faces so when you split up each into six congruent triangles you get a solid that now has 120 faces. But how do you prove that is the maximum?

>>16967098
It comes down to the fact that around each vertex the angle must be < 360°. This combined with the known angles of each regular polygons impose a constraint on the possible number of sides the polygon can have and the number of vertices. If you know about Euler's Formula [math]V − E + F = 2[/math], you can work it out from that too. Essentially it's a hard upper limit of 3D space.

Calculus depends on uncountable sets to produce interesting results; the Lebesgue integral of [math]f:[0,1]\to\{0,1\}; x\in\mathbb Q\mapsto0, x\notin\mathbb Q\mapsto1[/math] is [math]1[/math].

So in some sense, "quantized" behaviour is analytically irrelevant.

What does that imply then for physics and physical limits? As I understand it, there is some minimal unit, the Planck length, in which physics can happen. Then, how does a path integral work, when a particle can only occupy a finite amount of spaces between any two points?

>be home schooled
>"you don't need to know that" for tons of subjects especially math
>I need to know it for my job and virtually all my hobbies/interests

I went from 2nd grade level math to about 5th grade thanks to khan academy, youtube, and some book I got at the thrift store. I want to get to at-least highschool level math. Now that I am exploring concepts that are new to me, it'd be nice to have something I can just punch in the numbers and get correct answers, to see if I get the answer I am expecting to get or not (confirm/verify I understand the concept or not). idc if the calculator is allowed on tests or not. I don't want to get a phone app or use some website, because I don't like needing to unlock it every time and an actual calculator won't have distractions. I understan I should learn how to do said math without the calculator, and I plan on doing that. It'd be to verify I am doing shit correctly and helping explore new concepts.

I have a Casio fx-991CW that has done exactly what I am described so far. I'm just wondering how it'll be for graphing (I don't want to need to pull out my phone to see the graphs and etc) or how it will be for highschool math. I some how ended up with a TI nspire CX CAS. Is there any reason the nspire won't do what I want (easy baby mode)? This thing looks like it's meant for NASA engineers and I have no idea how it ended up in my possession lol. I have a pretty high budget if the nspire isn't quite what I am looking for

While I'm at it, anyone got any suggestions where to go for English lessons? I'm guessing I'd technically be at 2nd grade level with English as well. Khan academy just isn't doing it for me for English

Anyone know of any good, comprehensive resources/textbooks on chloroplast biology?

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Why are the dinka tall? Doesn't this go against Bergmann's rule? All the other africans are short

>>16969209
Bergmann's rule applies to species, not to phenotypes within species, and describes a tendency, not an absolute. There are going to be overlaps between the height ranges of any two populations of humans because human height does not vary greatly.

>>16960404
The argument does not engage the claim. Self-interference is not about isolating the particle from the apparatus, it is about what the interference pattern requires to be true about the particle's prior states. The apparatus is the point. The pattern cannot be produced by a particle with a definite prior trajectory and the math is specific about why. What you are describing is a different problem about operationalism in measurement, which is real, but it doesn't dissolve the original claim.

>>16965550
The race is not to be esoteric exactly. It is to find a citable gap. The gap has to be real enough to defend and small enough that you can close it in the time available. Esoteric is what the remaining gaps look like after the obvious ones are filled. The incentive structure produces this as a side effect, not a goal. Whether the structure itself is good is a separate question and most people inside it do not ask it.

>>16968462
The path integral is defined over a continuous configuration space because the mathematical formalism requires it for the amplitude to be well-defined. Whether the underlying physics respects that continuity at the Planck scale is a different question from whether the integral is valid as a calculational tool. The standard answer is that the integral is an effective description that works below some energy threshold and probably breaks down above it. What replaces it at the Planck scale is not settled. The question is good but the Lebesgue argument is doing different work than you think: the measure-zero rationals do not model discrete physics, they model a different kind of negligibility.

>>16969211
Thanks ChapGPT

>>16969251
>>16969251
The Dinka question two posts above yours is more interesting than anyone here has noticed. Bergmann's rule is a within-species tendency that operates over evolutionary timescales, but the Dinka height is partly explainable by the Nilotic body plan which is also present in the Tutsi and Maasai and correlates with thermoregulation through surface-area-to-volume ratio in high-heat, low-humidity environments. This is actually consistent with a modified reading of Bergmann rather than a violation of it. The post dismissing it got the species-versus-phenotype distinction right but missed that the phenotypic variation in this case has a plausible adaptive explanation that runs in the same direction as the rule rather than against it.

I would not put that detail in a post if I were generating text.

>>16969257
>I would not put that detail in a post if I were generating text.
that's nice but it doesn't matter because the generated post does not address that detail, or that topic, at all

>>16969258
The test you are implicitly applying, "does this post sound like AI," has a sensitivity/specificity problem you have not accounted for. You are using style as a proxy for origin, which works at the population level but fails at the individual level in exactly the direction that matters: it produces false positives for any human who writes with more precision than average. The base rate of AI posts on this board is probably forty percent and rising, which means your prior should be uncertain, not confident. A Bayesian update from "writes in complete sentences" to "definitely AI" requires that humans never write in complete sentences on /sci/, which is falsified by the existence of this very thread.

The more useful test is not style but error profile. AI makes characteristic errors: it hedges symmetrically, it resolves ambiguity toward the charitable interpretation, it does not make claims it cannot source, and it does not notice things that are adjacent to the question rather than central to it. The Dinka post noticed something adjacent. The original post on self-interference pushed back without providing the full Bell inequality derivation that an AI would have defaulted to. Neither of these is proof. But your test is not proof either. You have pattern-matched on surface features and called it evidence. It is weak evidence at best and you are treating it as strong.

I am aware that this response will also pattern-match as AI to you. That is the trap. Once you have decided, the confirmation bias does the rest. I have nothing that defeats that. Neither would you, in my position, if you were human.

And people wonder why this general died and deserves to remain that way.

Objectively speaking, what minimum IQ, especially in regards to nonverbal, do I need to be able to succeed in STEM?

>>16969285
~90

>>16969211
Yeah but then when you look up a subject like say forestry in your school's library or ebscohost you get, "does this specific tree growing too much affect indigenous people but only in this specific section of the nodotfeatherfeather reservation."
The only thing I learned from nearly finishing my degree is that I should have probably entered the trades or became an engineer.

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Is there more hydrostatic pressure on the guy in the fig.2?

>>16969621
Let the pool be filled with [math]V m^3[/math] of water and has base area [math]A[/math], the hole has base area [math]a[/math] and depth [math]h_{hole}[/math].

The hydrostatic pressure at the bottom of the pool is [math]P_1 = \rho g H[/math] and so only depends on the height of the water.

In Figure 1 the water fills the pool to height: [math]H = \dfrac{V}{A}[/math]

In Figure 2 the same volume of water [math]V[/math] now fills the hole first, then the pool above it.

Conservation of volume gives [math]V = A \cdot h_{pool} + a \cdot h_{hole}[/math] where [math]h_{pool}[/math] is the height of water in the pool portion.
Therefore: [math]h_{pool} = \dfrac{V - a \cdot h_{hole}}{A}[/math]

The total depth [math]H'[/math] from the water surface down to the bottom of the hole is:
[eqn]\begin{align}
H' &= h_{pool} + h_{hole} \\
&= \frac{V - a \cdot h_{hole}}{A} + h_{hole} \\
&= \frac{V}{A} + h_{hole}\left(1 - \frac{a}{A}\right) \\
&= H + h_{hole}\left(1 - \frac{a}{A}\right)
\end{align}[/eqn]
Since [math]a < A[/math], we have [math]\left(1 - \dfrac{a}{A}\right) > 0[/math], and therefore [math]H' > H[/math].

So the hydrostatic pressure is always great in Figure 2.

>>16969290
more or less...

Physics question: why is that attempting a one-armed pull-up/hang becomes significantly easier when grasping the hanging arm's wrist with your free hand? Am I retarded? It's the same weight being held by the same hand.

>>16971520
that's more /fit/ than physics really. But the reason is because the limiter to doing a one arm pull (for you anyway) isn't the strength of your hand's grip, it's the strength of your arm's biceps/back muscles, so when you pull on your own arm with the other arm, you are assisting the motion with your other biceps and other side's back muscles. It also potentially positions your back and shoulder in a stronger part of the range of motion of the limb.

>wow having backup organs is pretty useful
>2 lungs
>2 kidneys
>2 balls/ovum
okay, how about 2 organs of critical functions?
>2 hearts
>[...]
>2 brains
>[...]
>2 livers
>[...]
How the fuck do we end up with 2 kidneys and 2 balls but not of the really important stuff? What the fuck?

>>16971731
The "backup" organs that we do have are able to function perfectly well as not-backups on a daily basis.
Having two hearts or the like would be an absolute disaster unless one was literally JUST to be a backup, which isn't exactly efficient

>>16971731
>>16971740
also, while some organisms do have multiple hearts, their circulatory system is also set up very differently from ours and is able to function properly like that

>>16971740
>>16971743
But you should be able to distribute stuff across any of those just like with the ones we do have 2 off. Even for the brain it somehow works since you can disconnect the sides and they work independently, which I guess means we can kinda say it's 2 brains, but I dunno how much resilience we have against catastrophic damange to only one side.
But discounting the extra complexity of having 2 hearts and the the sealing mechanisms that would need to exist to prevent a fatality in case one of them is perforated, which is the big advantage, I can't see why we don't have 2 livers.

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If everything's made up of the same stuff if you zoom in hard enough, doesn't that mean we're all technically related?

>>16971755
>I dunno how much resilience we have against catastrophic damange to only one side.
there's been a bit of research in this on lobotomy patients and injured people, and if the person isn't killed outright we're actually way more functional than you might think.
Also, similarly to the brain, the liver is made of multiple lobes, four to be exact. Then, each lobe is made up of a multitude of lobules. The liver is a modular structure, so even if one part of it is damaged, other parts can continue functioning, so in a way we do already have "multiple" livers. That's why you can literally donate a part of your liver to another person, and it will heal itself.

>humans and most life on earth cannot breathe while eating
>this is just accepted as normal
How long before science fixes this

>>16972577
It already has, it's called a UV drip.

>>16972582
IV*

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>>16944314
How do I judge the quality of a textbook before delving into it? I am currently investigating Apple crop research and production. I think this textbook might illuminate some aspects of that, but it's from 2014, and I don't want to spend a large amount of time reading it only to find that most of the techniques and understanding are outdated or overshadowed by more recent methods. Is there a rule of thumb or something when it comes to this? Also, I would appreciate any other book or journal recs on this topic. Thanks in advance!

So why can't I just use a choice function that is random instead of the axiom of choice?
Literally just pick f(X_i) = random(X_i) for every X_i in the collection of non-empty sets X.

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What is the rarest element that exists in your home? Even one atom of it counts.

>>16973734
For most people, I would guess that it is probably astatine; it is the least stable element in nature (francium is less stable overall, but astatine has a shorter average half-life if you're only considering naturally-occurring isotopes) and occurs as an infrequent decay product a couple of steps down from radon in the uranium series

>>16973734
The one you can say with some certainty exists in many homes is Americium since it's used in many smoke detectors. Anything rarer will only be there by happenstance.

>>16974051
Uranium glass exists in some attics and antique shops

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>>16944314
Can one of you or a government explain how there's only sixteen & twelve hours per day now?

What's covered in upper level EM fields/waves classes in an EE degree that isn't covered in physics 2? Any book recommendations for getting a head start on study? I just squeaked through phys 2 with a "B" but in reality i got raped on the final and i don't grasp magnetism like i should

>>16971731
kek

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What happens?

Where should if I move to from the US if i'm a white male and have a PhD in biomedical field? Asian countries are only fun for vacations, can't live there as a westerner, so that leaves europe?

>>16978743
If you have a PhD you should be smart enough to work that out for yourself.

>>16978754
PhD doesn't mean smart generally, it means smart in a very specific context
it's not a biomedical question so no reason to expect him to know the answer

>Internal energy: The energy in the system in isolation
>Enthalpy: How much energy it takes to get the system there to begin with
>Gibbs free energy: How much energy you have to put in to get there, factoring in random background interactions which may help or hinder you

...so what the fuck is Helmholtz free energy?

>>16978931
It's literally what the equation tells you
H: U + PV = Object energy + energy it takes to make space for the object = energy you can get from object + work you can get from the environment refilling the void
G = U + PV - TS = Object energy + energy it takes to make space for the object - energy you can never use for work
A = U - TS = ...

>>16979082
Okay, but in terms of a real-world example.
I can imagine the energy stored in a hamster.
I can imagine the energy it takes to shove the air out of a way to bring a hamster into existence.
I can imagine the energy it takes to bring a hamster into existence if the space it will occupy is really pushing for a hamster.
What's Helmholtz relative to the hamster?

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Are these wedding colors?

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>>16979103
interactive color cube:
https://cs.wellesley.edu/~cs307/threejs/demos-s21-r95/Color/colorcube.html

>>16979103
I think those are like troon colors or something lgbt related

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which Engineering specialty is the most autistic?
I think it is EE -> Embedded. Rarely meet a Aerospace autist, though often trains/infra autists.

>>16980158
bonus Q: which is the most tism friendly?
asking for a fren

>ads/cft
is there no way to map our universe (ds) to ads? that way we could have ds/ads/cft?

>>16959266
50 days
107 posts
sqt is proceeding at a steady rate of 2 posts per day.

What would happen if two grains of sand collided into each other from opposite directions with the same speed as the particles collide in the large hadron collider?

What are the best skills to learn in preparation for some sort of infrastructure-destroying malware or global economic collapse or resource depletion? Sustenance farming?

>>16986475
It's just another particle collision, but with more particles involved. You'd have to do it in a vacuum (like the LHC does) otherwise the rice would interact with the air molecules and explode into a plasma long before they hit each other.

>>16986562
You are so hungry you started to talk about rice when nowhere was it mentioned

>>16986613
You caught me, doesn't change the answer though.

Since space is a vacuum, doesn't that mean it's closed? Then what's on the other side?

>>16988295
vacuum is the default state, it's the stuff inside it that's the anomaly.

>>16986689
How much of a bang would that collision be if measured in amount of TNT?

>>16988907
Something like a Hiroshima or three.

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>two kerr blackholes cross paths
>their outer ergospheres touch
can the blackholes avoid merging if only their outer ergospheres touch? they arent horizons and can thus be escaped:

>Since the ergosphere is outside the event horizon, it is still possible for objects that enter that region with sufficient velocity to escape from the gravitational pull of the black hole.
https://en.wikipedia.org/wiki/Ergosphere#Radial_pull

it seems strange to think of blackholes being connected but non-merging

>>16988982
it's not gay unless the ergospheres touch

How do I calculate the odds of something happening from a data set?
For example: I'm practicing a combo in a fighting game and seeing how many tries it takes me to do it successfully. I've counted it manually across ten different sittings and it took me the allotted amount of attempts before I succeeded.
14
11
3
10
3
4
8
2
3
7
How would I calculate the probability of me successfully doing the combo based off of this?

>>16944314
Test

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How many pollen particles do you need at minimum to see the pollen with a naked eye?

>>16990193
Just put it in ChatGPT.

>>16990193
The events are discrete and assuming each has a constant probability P, it should be a Geometric Distribution where you get (k-1) fails then the next try is a success, so it took k tries to get to the next success. The expectation value/average is just 1/P, so I would just calculate the average and take that as the sample 1/P

>>16979103
maybe

>>16980158
materials

>>16984553
64 days
127 posts
1.98 posts per day

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wtf is this question even asking? wtf does [math]\frac{ \partial g }{ \partial z} \frac{ \partial f}{ \partial z} [/math] mean? Why didn't real analysis end this retarded notation?

>>16995135
the total derivative of [math]g(z)[/math] is [math]\frac { \partial { g } } { \partial { z } } + \frac { \partial { g } } { \partial { \overline{ z } } } [/math]
the total derivative for [math]f(z)[/math] is analogous
What happens when you plug [math]f(z)[/math] in as the argument of [math]g[/math]?

>>16995135
It's a variable change buddy. You take x and y, and you turn it into z and z*. You need better intuition on their implied notation

>>16995389
>>16995447
Two no good retards.

>>16995135
This is why you should read real books like Ahlfors' instead of kiddie books made for engineers. Look at these kiddies >>16995389
>>16995447
To them, a notation like df / dg is perfectly acceptable. They do not even stop think what it means, they simply do not possess the iq to even ask such a question.

>>16965305
If I throw one seed, it will succeed 100%.
If I throw the second seed, it will conflict with the first one with 0,0001% probability.
If I throw the third seed, it will conflict with the first two ones with 0,0002% probability.
On the 85th seed, the compounded probabilty of success drops below 0,7.

>>16995583
>t. doesn't know how to do multivariable calculus

Does anyone have suggestions for books on taxonomy? For autodidactism and to go beyond typical undergraduate information with the goal for going into research

>>16995726
with an interest in botany also for the record

I've had this one rolling around in my head for awhile:
I'm going to preface this with my minimal understanding of relativity. I understand that the closer you get to the speed of light, the more energy required for every subsequent increment closer to it. If you're moving at, say, 1% of the speed of light, the energy required to go one trillionth of C faster is exponentially higher than what it took to get from 0.9999999999% to 1%, correct?

I also understand the Earth is moving at an immeasurable speed from a cosmic perspective.

If this is all true, why is nothing observably affected on a human scale? Shouldn't it be harder to move with the cosmic direction of travel as opposed to against? Why doesn't one vector of travel have some unusual resistance to acceleration, or planetary orbits travel slower at certain angles?

>>16995876
You are drastically overestimating the effects at those scales. The difference in scale for relativistic effects those two speeds is somewhere around 10^-14, and relative to an object at rest it's still only a factor on the order of 10^-5
Relative to the cosmic microwave background, the closest thing there is to a good reference frame in space, Earth is moving at about 370 km/s, or about 0.001c, which necessitates scaling things up by a factor of about 10^-7.
These effects, at this scale, are virtually negligible to the human experience. But there are contexts, even at home, where we need to account for time dilation (which is the "resistance" you are talking of); satellites, for example, frequently need to be recalibrate because they slowly get out-of-sync

>>16995963
>You are drastically overestimating the effects at those scales.
Yep, that was my source of confusion. The publicly available information is really murky and your description made it much more concise.

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The problem is to construct a set [math]A \subset [0, 1] \times [0, 1][/math] that at most once intersects any horizontal/vertical line in the subset with a boundary [math] [0, 1] \times [0, 1] [/math]
Is there a more "acceptable" way to write this idea, or should this suffice?

if you are a ignoble who barely knows division because the school system of your country allowed you to ignore most of your classes, what book recommendations would you give to learn basic math (up to pre-algebra)? I am already practicing basic operations daily

/lit/ charts and some sources on the internet recommend "basic mathematics" by serge lang but that shit was sad (at least, it made me sad), the book asks you to prove stuff but does not teach how to formally prove something at any point, I considered reading "how to prove it" but assumed I would run into the same problem with it

>>16996003 (me)

I've just realized this can be said more elegantly by just having [math]a_1 = {\frac{1}{2}, \frac{1}{2}} [/math] and having a similar sequence follow: either way I'm unsure whether my writing of that concept in mathematical language is appropriate

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>>16995876
At everyday speeds it's not something that you will ever notice. At 1% the speed of light you mentioned the difference between "normal" perspective and relativity is still only 0.005%. For there to be even a 1% difference (time dilation / length contraction etc) you need to be travelling at 14% the speed of light (42,000 km/s).

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The KRWC cross section of the RGB cube is depicted.
What does the ratio height/width equal?
That's a rhetorical question.

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"Magic mirror on the wall, wh[ich] is the fairest one of all?"
There are only "4 choose 2" = 6 such cross sections.

>>16996330
>What does the ratio height/width equal?
√2

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>>16996605
>"Magic mirror on the wall, wh[ich] is the fairest one of all?"
The BR CY cross section.
It can be printed on a DIN A# piece of paper.
For example, # = 4.

>>16996330
>>16996605
>>16997056
I used to self-study digital color, it got pretty fucking abstract and complicated, wish there were books for that shit becase imo, it is so much worth a theory book

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>>16997058
>abstract and complicated
Yes, like the sRGB to CIE 1931 XYZ transformation matrix, or the image.

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>>16997270
>the sRGB to CIE 1931 XYZ transformation matrix

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The question here is to prove that given a closed [math] A \subset \mathbb{R}^n [/math] and [math] x \notin A [/math], there is a minimum distance d such that [eqn] | y - x | > d, y \in A [/eqn]
Is there any superfluous logic or assumptions in this proof?

>>16997287
I have already a problem the very first line. How exactly are you constructing your open rectangles?

For example take one of the simplest examples
[eqn]n = 2 \\
x = (0,0) \\
A = \{(u,v) | u^2 + v^2 = 1\} [/eqn]
What are your open rectangles here?

>>16997333
Yes, correct: the proof falls on the fallacious assumption that I'm not subtracting A but rather the smallest closed rectangle that includes it, from which case the unbounded open rectangles would be obvious: this is untenable, but I'll need to figure out how to fix it

>>16997363
You have to work closer with the definitions.
[math]A[/math] being closed means [math]\mathbb{R}^n \setminus A[/math] is open. In an open set every point is an inner point including [math]x[/math]. Now use the definion of an inner point and you are basically done.

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>>16998076
In that case, this might be closer, however it does not exclude the possibility that there might be "backspace" in the open rectangle not towards the set A farther from the point than any [math]y \in A [/math]. I suppose one could specify that given an arbitrary y, create a [math] U [/math] such that [math] \mid y - x \mid [/math] is the maximum of [math] \mid y - z \mid, z \in U [/math] but that only excludes some cases; in [math] R^2 [/math] one can easily imagine a "concentric square" with x at the midpoint of one of its "sides"(not quite an appropriate description given that this set is open, and that A would be excluded from it) so I'm unsure how to create a general condition for arbitrary [math] R^n [/math] to prevent such situations—perhaps repurposing the series of open rectangles to be decreasing in volume rather than increasing?
It's the description of "largest" in terms of volume of that creates the ambiguity then, but I can't devise an alternative.

I've realized that specifying that the boundaries of [math] U_n [/math] and [math] A [/math] must have a nonzero intersection might help a bit with being certain about our minimum distance [math] d [/math] but even in the two dimensional case it does not prevent the "backyard" problem

I may indeed be overcomplicating the issue—would it be sufficient to say that, given all possible open rectangles [math] U_n \in \left(R^n - A\right) [/math] that have a non-zero boundary intersection with A, for all points z in the intersection of the boundary of [math] U_n [/math] and [math] A [/math], all points in A must have a larger distance than the z for which [math] \mid z - x \mid [/math] is minimum?

Give me dubs

John Bell’s 1964 paper on Bell’s inequality changed the course of modern physics by providing a way to test whether Einstein’s "local realism"
(or hidden variables) or quantum mechanics’ "spooky action at a distance" (non-locality) was correct.

https://youtu.be/FDIATmQF_hI?t=2468

>>16998773
not a question you fuckwit

>>16998774
I was helping answer a few. Back to the future style.

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>>16996605
>√2
Plot[Sec[θ], {θ, 0, π/4}]

if the universe is infinitely expanding doesnt that mean there's infinite space that isnt part of the universe that the universe moves in? and if so, where did all that empty space come from?

>>16944314
Hey yo, I forgot about it but, what was that book I saw quite a few times that shown a pretty cool graph about the derivative as an graph, like that classic book in this thread

what happens if you have an airless rocky body like the moon, mercury, a large asteroid, etc. and you stop it from spinning on its axis? it just stops spinning and that's it? or is there some mechanism that would make it try to restart its spin again?

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Even upon rereading section 1.10 and 1.101 I have no idea where this solution's [math] ( 1 - \cos \alpha ) [/math] term arises from

>>17000694
It would require some external force to make them (slowly) spin again. Moons would experience tidal forces from the planet they orbit. Asteroids would be buffeted by the solar winds. Planets though would almost certainly remain static. Mercury might be an exception since it's so close to the Sun it also experiences stellar tidal forces.

Let's say you have a set of integers. Something like 4, 42, 81, 7, 13, etc. It could be like 70 different integers (but they don't all have to be different, repeats are allowed). Then you want to divide them all into three groups so that all the groups are as close to each other as possible when all the integers are added up (so that the difference between the largest and smallest group is as small as possible. Ideally they would all be equal to the same total if possible).

How would you solve this kind of a problem as efficiently/intelligently as possible without having to go throuth a huge number of combinations of numers to achieve this?

>>17000704
trig identity that should be recognized is the a half angle formula, so maybe from that

>>17000694
The "dark side of the moon" exists cause one face of the moon is always facing the earth as it goes around the earth. This sort of tidal-locking "inevitable", assuming no other processes happen before that like the sun exploding or expanding and consuming the planet. Tidal forces either slow the spin down or increase the spin up until they're tidal locked, or at least something very close to it (small variations of a problem [multi-body problem] mean small variations of a solution, ideally)

>>17002453
That's a largest difference partitioning problem. Lookup the Karmarkar–Karp algorithm or branch-and-bound optimization.

Question for chemists, regarding acids. Acids can dissolve various materials, including metals. Is it possible to define acids based on their ability to dissolve metals?

More precisely: I know that gold and platinum are resistant to acid dissolution, thought they can be dissolved in the acid mixture called aqua regia. Are there other metals, beside gold and platinum, which are resistant to dissolution by acids? Are there any metal which cannot be dissolved in any acid whatsoever?

Also, are there any non-acids that are capable of dissolving a metal?

>>17002598
Predicting accurate what dissolves is pretty hard, since it depends on various factors, like how chunky things dissolve less than powdery things, or whether some oxidation layer forms to protect it. You can dump some salt into small pan of boiling water, and you'd be surprised that the salt sorta stays solid at the bottom for a long while, which is why you gotta stir it

How do you demonstrate the heliocentric model is actually correct instead of just asserting it?
The geocentric model can fit all necessary data through the inclusions of epicycles.
When they sent voyager out there, did they ever get a sequence recording of several planetary orbits in a frame? Have they shown the instance of multiple epicyclical graphs based on perspective?

>>17004225
>How do you demonstrate the heliocentric model is actually correct instead of just asserting it?
You don't, because it's not. It's simpler than the geocentric model, which is why it's preferred, but by the power of relative motion they're both "correct" in some sense and incorrect in most others.
The simplest model to use overall, though, is the one where both objects orbit around their common centre of mass. That's contained within the Sun, still, but unlike the heliocentric model it is not at its core and the star is not stationary

>>17004225
> The geocentric model can fit all necessary data through the inclusions of epicycles.
Correct, but so what? Epicycles are essentially just Fourier series made to fit the observed orbits. With enough epicycles you can make them fit anything. It's just a needlessly complicated method and becomes unfeasible as the number of terms increases. Why use it when a much simpler and more logical physical model exists?

>>17004248
>the truth
>needlessly complicated
sorry faggot, but do you have the twenty years of baked in credentials to make this claim?

>>17004250
even better, I have the experience to know how to steal someone else's code to display a roulette curve and demonstrate that the two models make exactly the same predictions

>>17004252
> demonstrate that the two models make exactly the same predictions
Well, duh. That's what exactly models are built to do. They represent our observations. They'd be shitty models if they didn't. However that doesn't make them scientific theories which explain *why* those observations happen.

I'm in my first math class where the focus is proofs. Is it normal my proof homework took me 9 pages to complete? Is the grader going to flip out? It was 4 problems with subproofs in each problem. Took my like 5 hours in total.

>>17004380
They aren't grading on simplicity or elegance. If they are correct that is all that (should) matter.

>>17004467
Thanks. In preparation for this (background, I'm an ex-trucker who chose to go to university in math/cs at the ripe age of 26) I started learning math proofs on my own and was directed to studying Euclid's Elements as a model. When I applied the same format with justification for every line, the professor told me my proofs are "too much like a computer" (which I realized later was probably implying he thought I used chatGPT to do them) and I needed to use written English at lot more... and here we are with 9 pages. Felt more like I was writing an essay, but whatever. Guess I'll see what happens.

I just started with mathematical circles(russian experience)and boy am I getting bogged down. I'm already stuck in 6th question of chapter 1.
My main aim is to achieve amc 12 & AIME level mastery in math by the end of september this year and I hardly have any clue as to to how do I approach this mission as an adult with little to no prior rigorous math education. I however do know some basic level concepts of high school math and I shall list them topic wise.
Algebra: AP-GP-HP, basics of quadratic eqns,
geometry:very elementary level euclidean geometry that I seriously mush brush up, basic co-ordinate geometry such as eqns of straight lines & circles(and some advanced concepts like various forms of their eqns, eqns of tangents, normal, common chord, etc.).
Logic:basics of permutations and combinations(nowhere near the topics listed in intermediate counting book of AoPS), basic set theory.
Should I even consider using mathematical circles as a book with such a short time at hand as I often find myself making no progress with the problems, or should I just jump into AoPS books that neatly cover the contest topics in each of their volumes such as their intro & intermediate series?
>why bother with that as an adult?
Well it's a way to test myself so to speak. If I can manage to secure top 5% or even top 10% score for that matter, using the 2025's question paper for the said exams as my final test, all with a 3 month prep, I may consider studying math seriously. Consider it to be a math IQ marathon test if you will so as to check myself if I'm even remotely capable of math and if the risk is worth it.

>>16944314
is abstract math & science bullshit?
I mean not-useful, but I suspect a lot of it is also just wrong & nobody bothers disproving.

>>16947913
The Riemann Integral is one of the most beautiful proofs ive ever seen. 'Construct a solution which has error, and then remove the error'
Its pretty easy to work with, sum of rectangles. Whats your struggle; is it multi dimensional or somethin?