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This is a moonlight tower. They were used at some point to try and light cities with moonlight instead of electricity, but because of the inverse square law, their design barely allowed them to make a difference in lighting at all. Is there any way these could have been made to work?
>>
>>14507466
A reflector on the top would have helped.
>>
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>>14507466
>They were used at some point to try and light cities with moonlight
>>
>>14507466
they just use regular lightbulbs, not reflecting the moon
>>
>>14507466
>They were used at some point to try and light cities with moonlight instead of electricity
What? Pretty sure that's not true. Perhaps they were used to cast light which mimics moonlight, sure, but using moonlight for lighting is surely impossible.

Previously >>14461881.

Talk math.
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>>14506744
A vector space equipped with a topology compatible with its algebraic operations.
That is, addition of vectors and multiplication by a scalar are both continuous.
>>
what did i do
>>14506365 has p +/- 1 elements, but the order of single elements under clock addition can be p^2 - 1
>>
>>14505149
I maintain that your second expression doesn't make sense, the expression should've been [math]\int_{x_0}^bv(t)\left(\int_t^b \phi'(x) dx \right)dt[/math], but your proof idea does work:
[math]\displaystyle \int_a^b \phi'(x)\int_{x_0}^x v(t) dt dx = \int_a^b \int_a^b\phi'(x) \mathbf{1}_{\{x_0\le t\le x\}} v(t) dt dx=\int_a^b v(t)\mathbf{1}_{\{x_0\le t\}}\int_a^b \phi'(x) \mathbf{1}_{\{t\le x\}} dx dt = \int_{x_0}^b v(t) (\underbrace{\phi(b)}_{=0}-\phi(t)) dt[/math]
>>
ignore >>14507202 i'm stupid and chose an invalid point
>>
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Anons, can someone help with this log. This comes out to a cubic equation and my prof said that we don't have to solve cubic equations, just quadratic.

I don't have have to solve for x, just have to get the left and right side to be equal.

I have been trying to solve this since yesterday, please help.

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Why people scared of spiders and bug but not lobster and crab?
>>
>>14507368
Crabs and lobsters are bulky/meaty, spiders are thin and wiry. Plus some, albeit very few, spiders are venomous while no lobsters/crabs are.
>>
>>14507368
For me it's centipedes, the creepiest invertebrates.
>>
Lobsters have the courtesy of remaining under water, and not generally where people are wading. Land crabs can be unnerving.
>>
Crabs trigger my arachnophobia a little bit. The main thing that makes me feel comfortable with them is that they're delicious. It's hard to be afraid of something you know is going to be your poop soon
>>
>>14507368
you can't eat bugs, no evolutionary incentive not to run away from them

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Listen up faggots. If you're below 145 IQ your existence is meaningless and you might as well give up and die. You will never, ever, accomplish any substantial work or discovery in STEM. Your papers will have at max, one reference from an obese landwhale in Academia who traced their thesis. No patents, no money, no glory will be achieved by your tiny, impotent mind. Below I have given you a mirror image of your mental capacity. It is not looking good and you should be ashamed of yourself, pig.

_,--. ,--._
\ > `-"""-' < /
`-. .-'
/ 'e___e` \
( (o o) )
_\_ `=' _/_
/ /|`-._.-'|\ \
/ /||_______||\ \
_/ /_||=======||_\ \_
/ _/==|| ||==\_ \
`'( ^^ ^^ )`'
\ /
\______|______/ hjw
|______|______|
)__| |__(
/ ] [ \
`--' `--'
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>>14506897
What a retarded attempt to sound smart.
>>
>>14506897
Everyone here including you is almost definitely slightly below or above 100 IQ, and no, this being a "science" board or you taking an online IQ test doesn't make it more likely you're smarter than that.
>>
>>14506897
>If you're below 145 IQ your existence is meaningless and you might as well give up and die
There are expected to be around 250,000 people in the world with an IQ of 160 alone, not even considering those with higher IQs. 145 is therefore generous.
>>
>give up, you will never gain social status

classic midwit
>>
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>>14506897
Okay, but you will never have sex. :^)

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>Use Dr. title in his videos and make it seems like he's an actual MD

>Make Videos about Medications and criticizing actual MD (some of whom are considered to be the best in their fields) and discrediting them, and spreading pseudoscience and retardness

>Make videos """analyzing""" People's behavior and make it seems like he's a psychiatrist or an expert

>Ph.D. in Counselor Education and Supervision (Meme degree)

>Freelancer

Some people have no self awareness,

Because of these Meme degrees, PhD now literally means nothing and they can't help you find a job
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>>
>>14505136
>Ph.D. in Counselor Education and Supervision

It's a vocational degree offered at the PhD level. Why does such a thing exist? What kind of research would one do in counselor education and is that something anyone would ever make a career out of?
>>
(((Dr Grande's))) "analysis" videos of current events is fake and gay. He's also a lefty. He is actually retarded.
>>
https://www.researchgate.net/scientific-contributions/Todd-L-Grande-71584318

He has 5 papers, the most recent is from 2014. They all seem to be using other people's systems and then presenting the results. Doesn't seem to be anything novel here.
>>
>>14505136
He's a soi with narcissistic personality disorder. You can tell just by the tone.
>>
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>BS in 2 years from Excelsior College
>>online university
>>unranked by usnews
>Masters from Wilmington University
>>Ranked 300+ in the country
>PhD from Regent University
>>ranked #266 in the country for psychology graduate programs
is he just a midlet?

Wannabe gun designer here, I'm working on an idea I had for a bullpup rifle that ejects cases forward through a a cylinder above the barrel. I've done some basic CAD modelling/sketches and I've ran into a problem - I'm afraid that if the ejection chute's diameter is too large, the cases could potentially tilt and get stuck. My current concept would be ejecting 5.56 NATO cases with a base diameter of 9.60 mm/0.378 in through a .06" or .07" ejection chute. The reason for the large diameter in relation to the cartridge size is that the rifle's bolt carrier is formed into a cylindrical tube with an ID of 0.4"/10.016MM, which itself rides in the ejection chute, similar to https://www.youtube.com/watch?v=J5x_clmnUjo

Any help would be appreciated anons, if you don't know what I'm talking about I'd be happy to try and explain myself better.
>>
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>>14507280
>*0.6" or 0.7" ejection chute
An example of what I'm talking about - a model of a 5.56 NATO case in a .7" ejection chute that's been tilted as far as it could theoretically be tilted. I'm afraid that the lip of the case could get stuck on the side of the ejection chute and then bend or otherwise get stuck if another case or the bolt carrier catches it the wrong way.
>>
>>14507280
Tapered tube.
>>
>>14507383
That could work but it would add additional manufacturing complexity, as well as reduce the mass of the bolt carrier... Either way, thank you.
>>
>>14507389
You can use a two internal diameters and a chamfer to get away from the horn. Gives you a couple of tunable parameters.
>>
>>14507280
>Any engineerfags here?
Mathfag here, but I worked in a gunshop one summer
(ultrasonic cleaning monkey) and I learned a lot from
the gunsmiths, who were always ready to talk about
what they know.
I recommend you find a local gunshop, and ask whether
any of the gunsmiths would be willing go look at your ideas.
Meet them at a pub, buy them a beer, and they will share
a hundred years of gunmaking history of what works,
and (more importantly) what doesn't, and why.
Beforehand though, admit to yourself that they know a
helluva lot more than you about guns, and be humble,
shut the fuck up, and listen.
They are the masters, and you are the initiate. Good luck.

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You are in crippling debt to impress your peers, right anon?
>>
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Not in crippling debt. No student loans because I went to a community college that my high school classmates mocked me for. Now my master's is paid for and I see these same people having kids in their mid 20s, probably hundreds of thousands in debt, because they realized they ruined their lives and have to make the best of it

I can't deny I feel smug
>>
no, they paid me to go to school
>>
>>14506961
I pay 300 euros a year to become a doctor
feels good man
>>
>>14506961
20,000 isn’t that much

This is real science: https://youtu.be/i_GtnTt-AZI
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>>
>>14504366
Sorry if it’s hard to hold an IPad still while taking a picture.
>>
>>14505859
If we could model these phenomena mathematically could we estimate how much energy was required to create said features on Earth, Mars, Moon, etc.? Knowing that would give an idea of how large and powerful the plasma was.
>>
>>14507366
https://youtu.be/6fjcPguafug

https://youtu.be/1xd-H_6VCzo

https://youtu.be/Kff_ytg0-8w
>>
>>14507366
https://youtu.be/WG8YRt4TvIk
>>
>>14507427
>>14507473
That's a heckin' lot of videos buddy.
Still thanks.

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whats the best refutation of flat earth?
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>>14507077
Ah, I spoke too soon, here ya go. A pedo has shown up right now here.
>>14507162
Have fun :)
>>
flat earth retards have made a strange model of the sun and moon but cannot explain seasons
>>
what if both models are wrong
>>
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>>14507183
>>
>>14507452
Wake up sheeple, the earth is a Calabi-Yau Manifold.

what occurs here
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>>
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>>14506839
Everyone within that Bok globule is allowed to say nigger in public.
>>
>>14506964
>>14506966
ok you're right and I'm a dumbfuck. the image is bernard 68 dark nebula. I don't know why this is always touted as Bootes void
>>
>>14506960

That is unironically a molecule and atoms are galaxies. I know that sounds ridiculous but so did germ theory and evolution at one time.

INFINITE FRACTAL UNIVERSE.

Bookmark this.
>>
>>14507032
I don't think it's retarded to believe we are just a tiny part of something else unfathomable to us
>>
>>14506839
gentoo installations

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https://m.youtube.com/watch?v=1L2ef1CP-yw

Why does setting the fan back from the window cause it to blow more air out?

Your explanation must satisfy newton's laws.
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>>
>>14502780
experiments in action!
>>
>>14502780
>. If it imparts kinetic energy to other stagnant room air it itself will slow down which cancels out
Slowing does not mean "cancelling out."
More air within the room has KE imparted upon it, ergo more air moves and more moving air = more air out of room. Simple.

>>14503897
>Yes
ok so it's not creating "pressure in the room" like you said

>Okay sure, but I'm speaking of volumetric. The amount of actual airflow
the amount of actual airflow is called "mass flow rate" not volumetric flow rate. The volumetric flowrate can change while mass flow rate and velocity stays the same because gas is compressible (can take up smaller volume)

>Also it's difficult to calculate with Boyles law alone because that's only in a closed system. This is like comparing a closed and an open system really.
>If we're to make a controlled experiment,
There is no confusion as to why a fan moves more air if it's inside the room I don't know why you are talking about experiments.

>the fan would be sealed all around the window and the room would be absolutely sealed. All the fan would do at that point is make a vacuum out of the room no? It would act like a compressor (or turbine?) under ideal conditions.
A house fan would not create a vacuum in a room this way because it's not powerful enough for it's given cross sectional area. Air being pushed out would be offset by air being sucked in between the blades for a net difference of zero. Otherwise you are just describing how a vacuum cleaner works on a bigger scale. Those motors have much much higher power to cross-sectional airflow area that can create net a net flow rate difference.

>In the same room, if the fan we then placed in the center then the air would actually have the ability to "flow" in and out of the system.

Comment too long. Click here to view the full text.
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>>14506164
>ok so it's not creating "pressure in the room" like you said
>but that air has to go somewhere though
If you're going for a "gotcha" then I'm simply gonna keep asking you reread what I said and stop being pedantic. What's more ridiculous is you then go on to prove that it indeed can create a pressure difference.

>There is no confusion as to why a fan moves more air if it's inside the room I don't know why you are talking about experiments.
This thread started with the premise of discussing an experiment and with OP asking the question, geez. I'm basically saying make the same damn experiment but more controlled. Also there is confusion, there are several answers in this thread and I am still unsure myself.

>Otherwise you are just describing how a vacuum cleaner works on a bigger scale.
I mean, basically yeah. So in other words it would remove the air not create airflow. There would be no air to move at a certain point. This is what I'm not understanding.

>You said "Placed near a window it's creating a vacuum which reduces air flow" which remains wrong
So why did you literally explain how it's actually correct and provided a real world example (the vacuum cleaner)? The only reason I'm wrong to you is "it doesn't have enough power and isn't in a certain geometrical form". As if that makes what I said wrong somehow? It's a motor with fins a circle you pedantic ninny.
>>
>>14506212
>If you're going for a "gotcha" then I'm simply gonna keep asking you reread what I said and stop being pedantic
Theres no gotcha. you were wrong and admitted it but tried to work around it to preserve your ego I guess?
>What's more ridiculous is you then go on to prove that it indeed can create a pressure difference
No, I literally said a house fan would not create a vaccuum/pressure difference in the room. A different more powerful setup could create a pressure difference, but fluid dynamics does not scale linearly with power so that different setup is entirely irrelevant.
>This thread started with the premise of discussing an experiment and with OP asking the question, geez. I'm basically saying make the same damn experiment but more controlled
And there is no need for any experiments. Several people in this thread have already answered OP's question correctly including me.
>So in other words it would remove the air not create airflow
What? Of course there is airflow if air is being removed
>There would be no air to move at a certain point.
No, I explained this already. Air being pushed out is offset by air moving back in at this "certain point" when the vaccum/pressure difference is large enough (which would be instant for a simple house fan no matter where it's placed). As others have said, the air-on-air drag effect from fan being in middle of room creates a more efficient mass exchange of warm air inside for cool air outside for the same energy input.
>So why did you literally explain how it's actually correct
You are very confused.
>The only reason I'm wrong to you is "it doesn't have enough power and isn't in a certain geometrical form".
You are wrong because you don't understand any of this and getting basic terminology wrong. A "powerful enough" fan placed near the window still would not restrict flow by virtue of creating a vacuum "near the window." What you said remains 100% wrong.
>>
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>>14507190
>you're right for the wrong reasons
>you're wrong for the right reasons

Should studies with zero reproducibility really have any say or influence over public policy?
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>>
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imagine how low iq someone has to be to trust the scientists
>>
>>14505783
Yes, that's why they were falsified in the first place. They can't serve their purpose if they aren't used to change public policy and perception.
>>
This happens because universities force you to publish some shit before they give you le epic paper.
>>
>>14505783
no.
>>
>>14505783
of course not, because then the theory of evolution would fail that requirement

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Besides a literalist approach how would /sci/ solve this puzzle?

Fleury's algorithm makes it impossible to satisfy the rules conventionally, so using eulerian trail arguments are out.
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>>
>>14504488
>https://en.m.wikipedia.org/wiki/Five_room_puzzle
i told you retards cannot be solved in 2d plane
eat shit my man
and I don't want to be scientist
i just want some person to be in this life with me
i have been to the depths of human and metaphysical i know everything and nothing
there for i am autistic
have nice day
sorry i feed you shit
i do not know you as u are
maybe there is good in you
we will never know
>>
>>14506292
this lack information, anyone who ever been in a flight knows you need to be in the location with the plane. We have zero info on where the location of said plane. Therefore this is not possible and also do your own homework.
>>
>>14497383
You can actually solve it if you think it in 4 dimensions, obviously I cannot draw that
>>
>>14499681
HOLY BASED
>>
>>14506292
>end of may
>homework
???
classes ended weeks ago

if you cant figure out that simple problem then why are you here?

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What is /sci/'s opinion on scientism?
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>>14506414
Science cant be used to determine normative or epistemological values... ignoring the religious part by the own definition scientism is stupid.
>>
>>14505108
Every -ism is shit, because it involves absolutes. And absolutes are basically faith. Faith is never a good guide for decision-making.
>>
>>14505108
>>14505111

The problem with scientism is the clerical style prestige with thich they give orders to the population, they give orders like it's the word of god (science says so!)

I'm pro vaxx with 3 shots, but I rememember how they (the experts) were against masking in the first months of the pandemic. I remember that because for many weeks I wore a mask and people looked at me like a mad man, since experts said it was not necessary. I was even attacked verbally by a doctor for wearing a mask.

Their opposition to masking was clearly a white lie, something they told people because masks had to be reserved and prioritized for health workers since there were not enough in the west for everybody (unlike China or Japan or South Korea). Once they had manufactured enough for everybody, they changed the script and abandoned their white lie.

I don't think it's acceptable to pretend to rule with paternalistic white lies from a class of experts.
>>
Just as useful and nice as capitalism. Mixed economy is almost the best really.
>>
>>14507066
>Every -ism is shit
Biology:
bipedalism
botulism
cannibalism
chromatism
embolism
geneticism
giantism
heliotropism
metabolism
organism
parasitism
rheumatism
synergism
thermotropism

Optics:
achromatism

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So if Webb fails to find anything suggesting life is Fermi Paradox actually going to become a real paradox?
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>>14505888
explain
>>
>>14475658

With the age of the universe there should already exist immortal civilizations or AI, we should find something observing the older galaxies, i think it's impossible to not be at least ONE civilization that is type 3 or above.

We are less than 10 years to create AGI, i believe it will happen before 2025, how is there not a civilization with millions of years that colonized various galaxies?
>>
>>14507037
>how is there not a civilization with millions of years that colonized various galaxies?
Stop pop sci thinking of multiple galaxies, galaxies are so far away it is sickening, and often when they are not far away they may as well be considered one, a cluster of stars in proximity, which is what a galaxy is.

It is suggested there is around 10 billion stars in our Galaxy (I love you God you are epic), I think the nearest stars to us as like 6 light years away.

Light travels like 298,000 meter/s (effing metric system bastards)(pretty intersting it's almost exactly 300,000, wouldnt that be spooky)

I don't know the conversions to miles and can't look it up now so I can't say any further.

Any way, stop the pop sci speed of travel fantasies too. But ok ok, maybe there is a good point of the millions of years bit.


If immortal AI robots were developed a million years ago.... Let's say, or 500,000 years ago, on a planet in a range, of 20 to 200 light years away.

And the best spacecraft they could muster travels 1/50 (and another example, 1/100th, and another 1/500th... I don't know what's feasible or the conversion rates at this point)

If they left their planet 500,000 years ago, how far would they have traveled from their planet in that time?
>>
>>14507037
Well that was half my point earlier, quasars could be type III civilisations converting stars into a more stable energy source.

We’re assuming all phenomena we observe is natural, and it’s only outlier “unnatural” events that could be signs of life - but if intelligence really is that common we’re probably already observing it.
Just, we’re trying to attribute “natural” causes to such phenomena.
>>
>>14462886
We're looking for life as we know it in particular. It's our best bet at finding something we are capable of understanding. If there's a cloud of refuse from some other kind of galactic empire, perhaps made of silicone or sentient AI, then perhaps we'll take a more general approach to trying to find what that new phenomenon is.




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