Archived threads in /sci/ - Science & Math - 473. page
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This is not a troll thread I obviously accept evolution as true however I have a question about it.
Over all of the history of earth and life on it wouldn't there have to have been an animal (obviously many but for purposes of question let's say one) an animal who never set foot on land but had a child that did?
I mean the very first lifeform that walked out of the ocean had a mother and father. What kind of animal was this?
If we put cameras on all the worlds shorelines and recorded them for a million years would we see an example of this happening?...
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>>7780081
... amphibians?
>>7780081
>Say we killed all human activity in Africa and recorded the whole continent for tens and millions of years. Would humans eventually be evolved again on that continent?
No because the climate changed, also there's no reason to develop a large brain there anymore so it would never happen
>>7780081
>If we put cameras on all the worlds shorelines and recorded them for a million years would we see an example of this happening?
I doubt it. When animals first came on land, there was an uninhabited ecological system to saturate. Now there are plenty of land based forms and amphibians already.
I don't even know when the last time was something walked out of water and became land based.
>Would humans evantually be evolved again on that...
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Learning from textbooks or learning from open courseware (such as MIT's proper courseware)
Which is better?
inventing your own methods like a fucking genius instead of being some fuckboy lapping up the genius of others
>>7779993
Textbooks
>>7780008
This. If you can't independently derive the laws of motion and thermodynamics and quantum mechanics using nothing but a 1kg block and the Calculus, you'll never get anywhere in science.
Wtf kind of equation accomplishes it achievable to allow you be incur the evaluation of the inquisition "does the Macrocosm subsist"?
>>7779987
Are you retarded?
>>7779997
can you provide a smart riposte of my inqusition sir
>>7779987
Remember when your teacher said there is now such thing as a dumb question? Well you seemed to have proven her wrong.
![image[1].jpg](https://i.imgur.com/gEVBc1V.jpg "image[1].jpg")
So I am in CP Biology and am currently learning about egg cells.
I have a question for /sci/
Can I reproduce with a flower by cumming on it? Will the sperm sink into the eggs?
>>7779934
What is your skin color and what flower are you tring to impregnate?
>>7779946
skin color is a social construct
fuck off racist
>>7779946
I am white (mostly of welsh descent) and i will try to impregnate any flowers that will work
"If anyone still wants to debate the viability of the scientific arguments regarding climate change, have at it."
You can quickly spot bad science when its adherents are extremely arrogant.
>>7779914
"Evolution is just a theory!"
"Gravity is just a theory!"
"The conservation of momentum is just a theory!"
Right... Totally an one sided thing there.
>mfw pure math autists give me shit for taking biochemistry
>hurr it's an easy science
Half you sperglords would fail the class
And you would fail out of any higher level mathematics autism course, or physics, or engineering or...
Different bases of knowledge. We need biochem fags to discover meds, and shit, just like we need pure math to sperg out and make mathematics that may one day have an application.
As long as you aren't shit at what you do, and you aren't being an autistic biofag doing work that has no medical purpose, then you are doing good work.
>>7779848
>reasonable way of thinking
How have mods not banned you yet?
Btw OP chemistry is just applied physics, enjoy your babby degree (^:
>>7779863
Except unfortunately for physicists, employers don't see it that way, and actual chemists have both the breadth and depth of their field that can only reasonably achieved from specialization. It would be nice if physicists could go into fields that are "applied physics", but the whole not specializing in it is a turn off for employers.
Consider an [math]{\mathcal L}^2[/math]-integrable function [math]f : {\mathbb R} \to {\mathbb C}[/math] with
[math]\int |f'(x)|^2 \ dx[/math]
finite.
How does the above integral stand in relation to
[math]\int |f'(x)| \ dx[/math]
?
E.g. are there some some standard inequalities relation them?
>>7779799
let f(x)=ln|x| for |x|>1 f(x)=1/2*x^2 - 1/2 for |x|<1
∫ |f'|^2 is finite
∫ |f'| is infinite
>>7779799
>reading zizek
I'd rather by a slob drinking beer in front of a computer.
>>7779833
but the log isn't in L^2 in the first place
>still on fourth grade math on khanacademy
Am I the only person here who never went to school and is trying to catch up to the rest of the world?
>still learning 4th grade math
>expects /sci/ to have empathy for him
I don't envy the responses you're about to get anon
>>7779794
Don't listen to the trolls anon, you're doing the best you can to learn. Keep it up.
>>7779794
Are you American? Why did you not attend school?
![sine-plot[1].gif](https://i.imgur.com/tGfNNod.gif "sine-plot[1].gif")
This seems like a silly question, but I'm not sure if it really is. A quick google search didn't really present me with too much info on the topic; maybe someone here might know.
My question is, how do we calculate the trigonometric functions? What is the "equation" that represents sine?
https://en.wikipedia.org/wiki/Sine#Series_definition
>>7779711
There are lots of different representations of sine, but the simplest would be the Taylor series: [eqn] \sin (x) = \sum^{ \infty } _ { n=0 } \frac { (-1)^{n} } { (2n + 1)! } x^{ 2n +1} [/eqn] You'd have to hold quite a few terms for it to converge to a reasonable accuracy as x gets larger.
>>7779711
The sine (and cosine) function, which you probably know can be described by the proportional sides of a right triangle, is a function which meets a specific set of properties (like sin^2(x) +cos^2(x) = 1, among many others) and we can prove that this is the ONLY function which meets these properties, proving it is unique. So you could argue that we calculate it through use of a right triangle and prove that it is a unique function in this respect in that it is the only function to have certain properties.
In...
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Doing some GOAT tier integration
>>7779467
you need to be over 18 to post in this board
>>7779470
gr8 b8 m8 i r8 8/8
>>7779467
>GOAT
>integration
pick one
but in all honesty, you could bait harder by posting unsolvable integrals with approximations used to solve them
Do we have free will?
>>7779339
yes
more so if you iodize your 5-ht2a receptor
any advice on someone who's been out of school for years who is taking this course? i certainly have to brush up on calculus because i scarcely remember that.
any advice for p chem i? or as my school calls it - quantum mechanics and spectroscopy.
pic related is the book we're using.
>>7779311
here's the syllabus.
http://chemistry.fas.nyu.edu/docs/IO/19766/CHEMUA651.pchem.quantum.turner.spr2015.pdf
There are chapters in the textbook that brush you up on some of the math. I guess I'll look at those rather than picking up and reading a whole calculus book.
>>7779326
>It’s important that you read the textbook!
>Alternate texts
>Radically different famous textbooks that do not cover the same material at all or is an entirely different level
>Recommended software
>Like everything fucking high level software instead of just saying "I'm probably going to use Julia for the course so learn that if you want to read my...
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>>7779348
>Radically different famous textbooks that do not cover the same material at all or is an entirely different level
What? Introduction to Quantum Mechanics by Griffths and Physical Chemistry by Atkins are frequently recommended as supplement/main texts for Quantum/Physical Chem courses. Harris and Bertolucci's Symmetry and Spectroscopy is more geared towards an Inorganic/Spectroscopy/Group Theory course but it's not inaccessible.
>Like everything...
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To keep a long story short, I'm doing some bullshit maths right now.
Does anyone know how to factor (x-y) in a general way?
And don't tell me I can't do it; I just need a function that turns subtraction into division.
>>7779258
Do you mean [math]x^2+y^2[/math] ?
>>7779272
sorry, minus not plus.
From Merzbach and Boyer's "A History of Mathematics" (good read by the way, heartily recommend) -
"The decimal system, common to most civilizations, had been submerged in Mesopotamia under a notation that made fundamental to the base 60"
>base
>60
Why? What would compel them to do this?
>>7779247
What would compel you to do base 10? It's all arbitrary.
>>7779247
Because fuck it, I made up a base 16 number system when I was little because I was bored. It has absolutely no effect on anything.
>>7779256
You actually want the number to be as composite as possible, senpai.
can someone explain to me why it's so important that N!=NP? i don't get it. what's so different if something can be expressed as a polynomial? i read the implications on wiki but those seem weird, like cryptography breaking down etc.
pic sort of related, is that even a polynomial?
>>7779201
If P = NP then that means problems that were before non-polynomial can now be solved in polynomial time. This has huge implications on cryptography in particular because modern day cryptography is based on prime factorisation which is currently an NP problem (a problem that cannot be solved in polynomial time). If it was proved that P = NP then these forms of cryptography would be "broken" and big problem would follow.
>>7779201
it's obvious that you open the thread with something interesting that you may or may not already understand just so you can hide you homework question in the end
fuck off
