Archived threads in /sci/ - Science & Math - 25. page

I would rather keep emitting CO2 into the atmosphere until someone comes up with an electric car that isn't a botnet

>>9163568
It's not even about CO2 nigger, Iran, Saudi Arabia, Qatar, Emirates are all threatening to collapse and they will only go with a big boom.

Parallel to that you have China surpassing USA, who might also become bitter about its decline.

WW3 literally when?

>>9163569

We could be buying from Venezuela but they playin

>>9169340
Looks like the type of guy that sits down to pee

>>9169340
fucking jew kike
https://www.youtube.com/watch?v=Beqtt42iDW8

>>9169390
Whats wrong about sitting down to per?

>>9169103
He has a PhD and he did real work for a while. He hasn't done research since 2008 though.
>http://www.haydenplanetarium.org/tyson/curriculum-vitae#research

>>9169103
His ability to popularise astrophysics is good enough by itself. He's also like the one reason not to hate all blacks.

>>9169107
i think there are smarter black dudes in the math dept at my university.

After further googling wikipedia tells me ''Although the candela is now defined in terms of the second (an SI base unit) and the watt (a derived SI unit), the candela remains a base unit of the SI system, by definition."

So even though I'm right in that the candela is derived, it is still considered a base unit?

>>9169051
Current is not energy, it's charge, so I don't think you can define an ampere as energy, since current i =dq/dt

>>9169095

I guess I can see that, but now that I look up current (flow of a charge), isn't that just coulombs/second? Coulomb (charge) seems like the more fundamental unit.

Electricity is where I get really retarded, so I might actually just drop this path of thought at this point.

Realized I spelled Theory wrong, was in a rush.

>>9168925
>was in a rush.
I totally understand man. I mean, you really had to make this shitpost. Good that you rushed! I can't imagine having to wait a single second more for this piece of shit thread.

Fuck off. Elon Musk is a cunt. A stupid cunt. Muh AI muh ST

If you want to read about the ST, go read Nick Bostrom. Not Elon Cunt

>>9168799
>zero visual intuition
You mean like the Fourier transform for instance? That deals with vectors of dimensions usually 2^10+, for which there's no visual representation for, and yet there's an innumerable number of things this is useful for (to take a mundane example: noise cancelling headphones wouldn't work without that branch of, as you say, "symbols games")

>>9168962
>no visual representations
There are mathematical distributions such as the Gaussian for example that are the Fourier transform of itself. Fourier analytics in physics is important in the context of distributions for which there is plenty of visual intuition for.

For example, odd functions such as sin(x) have imaginary Fourier transforms because they are "imaginary" in nature - if you went to the casino would for example you expect the probability of you losing to be negative?

>>9168799
>needing visual intuition
Stick to engineering.

>>9168513
>What do these axes results mean?

It's just a change in basis.

>Is it implying that you first took a measurement with respect to the z-axis, THEN measured either x or y?

No, if you measure with respect to the z-axis you would get |+z> or |-z>. Lets say |+z>. Then the probably the 2nd measurement wrt the x axis will be positive will be <+x|+z>^2=0.5 and will be negative is <-x|+z>^2 =0.5.

>>9168535
>>9168535
>No, if you measure with respect to the z-axis you would get |+z> or |-z>. Lets say |+z>. Then the probably the 2nd measurement wrt the x axis will be positive will be <+x|+z>^2=0.5 and will be negative is <-x|+z>^2 =0.5.

Right, makes sense and lines up with the thought experiments (stern gerlach).

But for some reason I still can't wrap my head around why these are different. I understand they're a change in basis, orthogonal, and all that jazz, but for some reason I can't conceptualize it...

File: Monogatari.full.1427492.jpg (482KB, 1000x1000px) Image search: [Google]

482KB, 1000x1000px

>>9168574
To convince yourself of this, calculate the eigenvectors of the pauli spin matrices for a spin -1/2 particle. For example:

Sx |+->=j|+-> implies that mat (-j,h/2,h/2,-j)=0.

Det (mat (-j,h/2,h/2,-j))=0 implies that j=+-h/2.

Forj=+h/2, mat (-1,1,1,-1)×mat (x1,x2)=0 implies that x1=x2. Since x1^2+x2^2=1, 2x1^2=1 implies x1=+-1/(2)^2. This means that the spinor is (x1,x2)=(1/(2)^2,1/(2)^2).

For j=-h/2, the eigenst in or comes out to be (1/(2)^2,-1/(2)^2).

watch back to the futer

The process involves some pretty potent acid that i doubt you could get your hands on.

Not to mention that 1 kg of uraninite contains what, less than a fraction of a fraction of a fraction of a fraction of a gram uranium

>>9168492
Doing some pretty basic math, I figured my samples are all around ~20% by mass Uranium, given natural Uranium clocks in at about 25000CPM, and my most active sample (104g) measures right around 500,000CPM.
https://www.youtube.com/watch?v=BRdZouC7CRo
Vid goes kinda in-depth, but is a little too sketch for my liking. HCl is literal shit-tier acid, I have 9L total in a few different concentrations. H2O2 and bleach are readily obtainable from everywhere.

thats right. Americans always butcher things up with "science"

Cringeworthy teenage opinion thread

>>9167869
Wrong. Science is in its strictest sense a body of knowledge that represents the set of all truths. A particular science is a set of truths for a particular subject.
The scientific method is not an innate part of science.

>>9167569
Well first you need to understand how echinoderms come to have radial symmetry. Bilateral symmetry is conserved in larvae of echinodermta, and develops into a radial-symmetrical form during metamorphosis. like this https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2176165/
Now for the interesting part, eco-evolutionary dynamics. it will help if you have a basic understanding of the material reviewed here https://sci-hub.cc/http://www.nature.com/nrg/journal/v16/n10/full/nrg3982.html
A few hypothesis start to come to my mind. If we take this hypothesis for the common ancestry of echinoderms to be true as i found it on Wikipedia
>It is hypothesised that the ancestor of all echinoderms was a simple, motile, bilaterally symmetrical animal with a mouth, gut and anus. This ancestral stock adopted an attached mode of life and suspension feeding, and developed radial symmetry as this was more advantageous for such an existence. The larvae of all echinoderms are even now bilaterally symmetrical and all develop radial symmetry at metamorphosis. The starfish and crinoids still attach themselves to the seabed while changing to their adult form
and use it, or atleast something like it as an axiom for forming new hypothesizes.

File: AJBC1430.jpg (226KB, 700x550px) Image search: [Google]

226KB, 700x550px

>>9167779
There are a few insights that this gives
1, that the mutation causing radial symmetry was selected for its evolutionary utility to a specific pattern of ecological and/or biological behavior (neolamarckian selection)
possible examples include but are not limited to any one or more of the following; Movement ((mobility in a bethnic environment better allowing for; increased ability to find food(finding the right physiological oceanographic conditions for filter feeding), escaping predators, finding mates and mating, and thus survival to reproduction and recruitment.), Maturation (knowing that bilateral symmetry was preserved up until metamorphosis when the larvae attaches itself to the sediment to form into adult it follows that any mutation that benefited this behavior would be selected for, if in some way radial symmetry bettered allowed for the recruitment of larvae into juveniles, or juveniles to sexually mature adults, i would need to do some more research to start on this one. some other things that come to mind are the ability to fully rejuvenate tissue, better digestion or physical ability to eat, perhaps something to do with neurons.
there is alot of possible explanations and i dont even have the time to discuss what i have already brought up.
im going to leave now. in the mean time i would be happy if someone would bring up mores questions pertaining to this or ecology evolution and marine biology in general
talking about this for cnidarians or the evolution of decapod crustaceans into crab like forms

>>9167569
>Does anyone here have any theories on why echinoderms evolved pentaradial symmetry?

Why not?

>>9167214
I'm thinking of doing marine biology next year
What is the least saturated field and what is the most rigorous field and what is the field with the most potential for new groundbreaking discoveries?

>>9167214
I find all biology quite interesting but I'm dropping in to say FUCK JELLYFISH AND EVERYTHING RELATED
That is all

>>9167214
wish freshwater biology was more prevalent

Ah, this is a much better name. Finally.

Anyway, I need the angriest mathematician on this board!

BECAUSE I AM THE MOTHERFUCKING GOAT!

Well, since i'm human scum I can't post it to arxiv.org

It's done though anyway.

Anyone here capable of validating my endorsement code?

garbage thread
/thread

>>9168592
What is this?

>>9168606
Just another (k)not theorist meming about his irrelevant field.

>>9168592
I think using meaningful shapes is better than using arbitrary placeholder symbols (numbers being the latter) because that Daniel Tammet autist can effortlessly calculate by imagining pictures, and as far as I know he's the only savant who has a verified approach to how he does what he does that he's able to describe and reliably reproduce (e.g. he was tested by being asked to make his imagination of different random numbers using clay and then called back in at a later date and asked to make the same numbers to make sure his shapes were consistent and not just made up on the spot).

>>9168187
Pshh no he is just trying to buy himself time so he can hijack a boat.

>when your Tropico game goes to shit and the last time you saved was 2 hours ago

>>9168187
It will probably work better than socialism.

>>9167542
Convince her to do an ancestry test for fun

>tfw 5% ashkenazi

File: 1504709332952.jpg (32KB, 400x382px) Image search: [Google]

32KB, 400x382px

Post your cranium OP /sci/ must approve of your PHENOTYPE before we allow you to defile a Jewish womb.

File: 1454786540290.jpg (20KB, 500x313px) Image search: [Google]

20KB, 500x313px

>>9167542
>>ironically shitpost