Archived threads in /sci/ - Science & Math - 380. page
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ITT common falsehoods the average public believe about science that pisses you off
>Natural selection is the survival of the fittest
>Fittest meaning strongest and most ruthless
or
>People who get hypothesis and theory confused
>>7811179
Nice blog post.
>>7811179
These are the sort of things that a middle schooler might get annoyed at.
>science is facts
So I was talking to a practicing medfag recently about her daily work and I came away with the conclusion that software could easily do most of their work. That does not mean they should be scared losing their work in the near future, because of strict regulations to tackle about responsibility and some people require human interaction, but I feel we are approaching peak MD fast.
It might be a bit counterintuitive, because doctors need lots of high level education and training, and they like to think it is a prestigious job, but her points were the following
1. People can identify common diseases and most can be treated with otc drugs
2. Where symptoms are ambiguous, you need to run some specific tests and evaluate their results
3.a you can either prescribe some drugs to the patient based on some preferences, like medical history etc
3.b send to a specialist for further
And these cover 90% of the use cases. It does not even need a complicated AI but a simple look up table.
>>7801824
>>7801824
absolutely. 200 years from now, if global caliphate or world war III won't happen, people will just step into a box. the box painlessly takes a drop of blood, runs a couple of medical imagining procedures and will suggest a diagnosis/treatment based upon checking thousands of biochemical parameters in a fraction of second. 500 years from now, if ayy lmaos won't wipe out our cosmic dumpster-planet in a preemptive strike, there won't be any illness anymore.
>>7801834
might be, but I'm talking about the next 10-20 years, and that the technology is already here.
>>7801824
Shit, you don't need to do all that. As a medfag myself, if you can just make a program that does two things I'll buy it and install it in my office tomorrow.
> a machine that can diagnose patients with a viral chest infection and convince them that antibiotics won't make them better and them feeling better when they take them is just a coincidence
> a machine that convinces people that they don't need a test if the outcome of the test won't change the management or doing a test without a reasonable Bayesian pre-test probability produces uninterpretable results and useless false positives (e.g. people who get full body MRIs for no reason, screening with PSA, routine chest XR for no reason, etc)
Just doing that would revolutionize medicine and save the system tons of effort and money. Please, please, somebody work on this.
>professor explains a long proof
>ask him why we couldn't just subtract here and cut the proof in half
>"sorry we haven't defined subtraction yet"
When did you realize majoring in math was a meme?
Math is just applied philosophy, if you think about.
>>7813774
Just start your undergrad? What objects are you assuming you can subtract?
kek OP, I remember that with division. You get used to it. The way math is done, with definitions, theorems and proof, is hard to get your head around at first. Once you get it you, you get it, and becomes awesome and you start wishing everyone else had that kind of rigor.
No one in /wsr/ will know this,
Please, if there is any anon who knows physics:
how can you find acceleration just knowing initial and final position and velocity?
>>7813729
btw, constant acceleration is implied
[math] v^2 - {v_0}^2 = 2a \Delta x [/math]
Can anyone point out to me where in the work I did in pic related is wrong? It's a thermo problem.
"A rigid, well-insulated gas cylinder initially contains N_o moles of an ideal gas at a temperature T_o and pressure P_o. A venting valve is opened and the gas is pumped out of the tank. Derive an expression for the instantaneous temperature of the gas as a function of the number of moles remaining in the tank. The heat capacity at constant volume of the gas is independent of temperature.
I forgot to edit it out in the picture, but I am assuming dN_out to be equal to dN since there is only one output stream in the system.
Shameless self-bump.
>>7813559
Yep, gas looses energy/ heat as it expands. Why your A/C works. Look over your math and find what you did wrong.
With regards to motion, what is the difference between irregularity and randomness?
>>7813466
The Irrationals variety and conduction with previous inductions of entropy in regards to what could Potentially be its immediate enviroment
>tfw can't do Hilbert style proofs in propositional logic
Kill me now.
Can someone give me some tips? How do I "see" what sort of wffs to plug into the schema when doing a proof? Here's an example (> for if..then):
Prove that A > A
1. A > ((A > A) > A) /// instance of H1
2. (A > ((A > A) > A)) > ((A > (A > A)) > (A > A)) /// instance of H2
I'm not gonna type the rest of the proof, but you get the idea. How do I figure out that I need to substitute (A > A)...
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>>7813432
bump for 90's powerpoint template
what is mp? are each of these statements "bar"d?
>>7813530
Modus ponens. Not sure what you mean by bar'd.
>The powers at be no longer have to ban and burn books to prevent the spread of knowledge
>They just jack up the prices 2500%+
>And no one is none the wiser
Why is this allowed
>>7813385
You can just pirate it.
Most specialized textbooks are also available in draft form (i.e. grammatical errors, formatting errors) and free.
If you want a hard copy, you can just go get on in your library.
The price of those books are high because no one want to buy it except for a few autists and libraries.
>>7813385
College is a scam industry, you think the textbooks you're forced to buy are going to be inexpensive?
>>7813385
>buying a new copy of the latest edition of a textbook.
the second edition is 12$ used off amazon. i can tell you haven't been in school very long because you seem to think there is this huge difference between editions.
protip: there isn't. the books are identical with the exception of a few examples and citations.
What field of pure science gives me the greatest chance of working in a noneducational career in that field with an:
A) Bachelor's degree
B) Master's Degree
C) PhD from an average uni
>>7813313
how "pure"? if you go off the deep end (theoretical physics and pure math) you don't have much chance out of academia. if you accept applied math or applied physics you can do tons of shit from finance to modelling to who knows
>>7813328
You don't know what you're talking about.
Applied math is garbage. Pure math is gold.
>>7813313
>pure science
>not in academia
pick one. applied science is the only thing industry gives a shit about.
at a minimum you are going to want a bachelors in some kind of engineering just for legal reasons.
Can anyone recommend a good Trigonometry book? I'm interested in learning deeper and more advanced Trig than the surface stuff covered in Pre-Calc and want a very strong foundation in it before I go into Calc II.
how could you even make a whole book on it, its basically just one function
>>7813110
Just... memorize the unit circle and figure out the basic identities like sin^2 + cos^2 =1 or derive double angle formulas from e^ix = cosx + isinx...
Even if you don't know any of this yet with what I just told you and your existing enthusiasm you'll be done in a week. It's cake and most people learn it in panic mode in calc or intro physics anyway.
>>7813121
My uni offers a full semester course in it. Not sure if that means it's slow/ remedial or more in depth, but it's closed to anyone who's taken precalc.
working on:
projecteuler.net/problem=544
Let F(r,c,n) be the number of ways to color a rectangular grid with r rows and c columns using at most n colors such that no two adjacent cells share the same color.
found a generalized formula for F(2, 2, n)
looking to extend this to F(r, c, n)
I have:
((n-1)*(n-1)*(n-2)+(n-1))*n
for 2x2 grids
because 1st cell has n choices, 2 cells adjacent will have n-1 choices followed by the last corner of (2n-3)
applying my logic to the 4*3 grid, i get something like 6*5^8*4*4*3 which is off by...
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>>7813073
I have done a similar algorithm in the past.
I assigned a color for each digit (0,1,2,...,9)
(so it worked for up to 10 colors ...)
Tested all permutations (some optimization allowed to only test reasonable permutations).
In the case of a 2x2 matrix and 3 colors it worked like this
0000
Test: "fail, add one in base 3"
0001
Test "fail, add one in base 3"
0002
Test "fail, add one in base 3"
0010
Test "fail, add one in base 3"
....
2222
Test...
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>be viewing anaglyph 3D images
>green-magenta glasses don't work with the majority of blue-red anaglyph material
>flip glasses around
>they work
how does light work?
>>7813028
You need 2 converging images, bro.
Hello,
I have what seems like a really simple question but I have a hard time finding an answer just searching though the internet.
I am looking at a resistive circuit, the point of which is to generate heat.
I know that voltage = Current x Resistance
So, since I am using household voltage (120 volt nominal) and my circuit breaker says that it is rated for 15 amps per circuit with a maximal continuous load of 12 amps, does this mean that to reach the maximum allowable wattage I need a minimum of 10 ohms of resistance to run continuously?
Then,...
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>>7812958
Theory is fine too, then I will test it to get real world data, but I can post this over there as well if this is too simple a question.
I am also wondering how to produce the most heat out of a circuit like this, or is the amount of heat produced pretty much the same regardless of the size/thickness and so one of the resistor?
>>7812967
Look into heat pump if you're concerned about efficiency.
If you had a small wind tunnel to do experiments what are the formulas for wind speed and your model's properties?
For example if I have a scale model where 1 pound is actually 1000lbs and my tunnel wind speed is 10mph...does that simulate a higher wind speed for the model?
Can you approximate stability and aerodynamics of a scale model with slower wind speeds than what the craft would actually experience?
>>7812855
https://en.wikipedia.org/wiki/Similitude_(model)
>>7812878
thanks m8 now I have a starting point to search from
>>7812855
REYNOLDS NUMBER
About 3.2 billion people – nearly half of the world's population – are at risk of malaria. In 2015, there were roughly 214 million malaria cases and an estimated 438 000 malaria deaths.
And yet DDT is banned because it might have a link to cancer. Thank you ecological scientist mans.
Half a milliion deaths + 200 million infections + 3billion in danger
up against
white ecologists who went to college and now they have to achieve something
>>7812753
It's not just because of cancer. DDT was also bioaccumulating and wiping out tons of birds. It drove dozens of species to the brink of extinction.
Liberals gonna lib
But it was probably one of those eugenics things, you had a lot of these progressives who absolutely hated the non-whites once upon a time.
>>7812760
>It drove dozens of species to the brink of extinction.
Let's see here: https://www.google.si/webhp?sourceid=chrome-instant&ion=1&espv=2&ie=UTF-8#q=how%20many%20species%20die%20each%20day
>Scientists estimate that 150-200 species of plant, insect, bird and mammal become extinct every 24 hours.
Now over 150 species die out each day and somehow, biologists (a real science?), were able to calculate how many species died from...
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