/sci/ - Science & Math

It's a Calabi-Yau manifold.

It's a fleshlight for string theorists.

It's a Calabi-Yau manifold.
http://en.wikipedia.org/wiki/Calabi%E2%80%93Yau_manifold

>>3997715
>>3997719

Yes, thank you... I can read too. Now tell me in specific ways how it deals with String Theory.

who cares about string theory, LHC experiment results disagreed with the theory anyhow. Bunch of faggy old theoretical physicists being dogmatic about their theory

>>3997730
there are 6 extra dimensions that are curled up and look like that. well, not exactly, that's just a 2d projection of a 3d slice of the 6d surface in a higher dimension.

>>3997742
>a 3d slice of the 6d surface in a higher dimension

ok... now very slowly explain that. plz use bullet points

>>3997737
who cares about string theory, LHC experiment results disagreed with the theory anyhow. Bunch of faggy old theoretical physicists being dogmatic about their fiction.

>fix'd

>>3997749

its a 2d representation of a 3d representation of how the 6th dimension looks, or something like that

>>3997749
-a plain is 2D, it has length and width (x,y)
-a cube is 3D, it has length, width and height (x,y,z)
-a hypercube is 4D, it has length, width and height and niggerballs (x,y,z,t)

-take a cube and slice it in some way, the place you slice it is now a flat 2D plain
-take a hypercube and slice it in some way, the place you slice it is now a flat 3D cube

then repeat this until you get to (x,y,z,t,v,w) then its 6D.
so to get a 3D slice its like taking a single point of a cube, because you reduce the 3D to 0D (a point)

>>3997771
0/10

that's clearly just a crumpled up piece of pink paper

The mashed up some mobius strips because, wow, mind blowing complexity of math genius.

>>3997777
What are these additional dimensions made of?
I mean mathematically.
The first 4 dimensions are usually described by real numbers.
Does that apply to the other dimensions too? Or are they described by other sets?

Sting Theory = total horseshit. that shape is utterly meaningless. not trolling, prove me wrong

>>3997804
infinitah

>>3997804
real numbers
>sets
the topology will not be that of R^10 (just like a circle S^1 isn't R) but you still use reals as underlying field.

Otherwise you couldn't for exmaple imbed D-branes
http://en.wikipedia.org/wiki/D-brane

>>3997804 The first 4 dimensions are usually described by real numbers.
Not really, no. First, there are no "first four dimensions", second they're not necessarily described by real numbers.

>>3997838
>>3997840
Holy shit, both experts are online now.
May I ask you to enlighten me?
What is string theory all about?

inb4 wikipedia: Yes, I read the article and it wasn't revealing much of the theory.

>>3997840
Real number = Dedekind cut = set

How do you tie together General Relativity Theory with Quantum Mechanics Theory?

With String Theory.

>>3997838
>>3997840

total horseshit

>>3997875

tl;dr - /sci/ doesn't know shit beyond the easiest wiki articles. Once you ask them about complex mathematics, or to explain lie algebra, or anything that wasn't mentioned in their electives during undergrad (if you are that lucky), they fall to pieces.

Let's have another religion thread.

>>3997875
with LQG or twister theory

>>3997893
>>3997893
did you miss the post that explain it?

>>3997893
>implying their isnt real scientists on /sci/

>>3997897

Oh what, the

>>3997715 file name reader?

>>3997719 wiki link?

>>3997742 herp derp youtube video-grade patchwork response?

>>3997777 Dimensional analysis any middle school-er could come up with that only de-mystifies an already shitty response?

>>3997838 Two retards who hounded on him
>>3997840 for being *summer*, proud they could at least show they aren't brain dead yet still not answering OP at all?

Right.

>>3997866
>What is string theory all about?
About (quantized) strings as fundamental objects in spacetime. This is too vague.

I don't really know why Josef is saying you don't need reals. Eighter he's taling about the fact that Calabi-Yau manifold are complex, in a generalized sense, or he's talking about some post apocalyptic (post-quantized) scenario where you only use spectra to describe spacetime and you don't have real neighborhoods.

>>3997867
I'm not denying sets of reals being sets. I wanted to seperate R from any real manifold. (any manifold with R^n as tangent space.)

>>3997875
Where do you disagree?

>>3997906

There might be but 95% of /sci/ cannot solve quadratic equations for all the talk of string theory and Ph.D's in math.

>>3997915 a troll

>>3997918
>About (quantized) strings as fundamental objects in spacetime

Okay but is there anything you can say about string theory that goes deeper and can still be understood without knowledge of "Calabi-Yau manifolds"?

>>3997922

How am I trolling? Are there any untruths in my posts? I'm calling all you shitty faggots out for the shitty faggots that are.

You can't into science questions.

All you're good for is adding to the cacophony that follows any thread with the topic of Nigger Vs Whitey, IQ SCORES, Religion is for idiots, /x/ rejects, and so on.

And you're proud enough to wear a tripcode. What, so you can look back on all the times you explained the Pythagorean theorem to a homework fag rejected from /b/?

Right.

>>3997932
what is your background?

>>3997918
Obviously sets of reals are sets by definition. I'm saying a real number is a set of rationals by construction.

>>3997936
Probably what you would call undergrad level.

>>3997941
>>3997918
>>3997867
>>3997840
>>3997838

Lol at your experts. They're all getting butthurt mad arguing about some offhanded comment you made that wasn't even related to how that manifold relates to string theory.

Stay tripfag /sci/, at least EK answered OP.

>>3997919
Not to mention not being able to wipe their asses without their moms' help.

thyeince

>>3997937
>You can't into science questions.

How about you post some of these instead of t̶r̶o̶l̶l̶i̶n̶g̶ shitposting?

>>3997918
Where do I disagree? Quantum mechanics is much less complete to figure how all the pieces fit. And untestable theories should be rejected as non-science.

calabi-yau manifolds are potential ways that the curled up spacial dimensions beyond our own are composed. string theory mandates a certain number of dimensions (10 or 11 or whatever the fuck it is now) to exist for them to "have enough breathing room".

not much else to say on the topic without having to know how they work and what you can do with them.

mathematically, it's going to be R^10, in the same way that spheres, tori, and klein bottles are R^2.

don't quote me, though.

>>3997958

/sci/ has never been able to answer my questions. Once when I was a stupid shit they struggled to answer a speed of light question for me, a topic that is easily understood once the appropriate courses are taken in college. You fuckers stumbled around for 50 posts and couldn't into the right answer. I learned a year later how to answer my own question from a physics 3 course in college.

tl;dr I don't ask questions on /sci/ because I can read Wikipedia just as well as they can.

>>3997969

so do we live on one or what?

>>3997969
Nice. That was a clear description and easy to understand.

Now how do these calabi-yau manifolds work and what can you do with them?

>>3997988
>implying you would even understand if I explained what you can do with them

>>3998001
Then try your best.
If you fully understood the theory, you should be able to explain it to an idiot.

>>3998014
>trying to explain anything to an idiot

>>3997946
which year/semester?

The basic idea is that you quantize not a particle (worldline four vector x(\tau) in spacetime, \tau a time parameter) but a string (worldsheet x(\tau,\sigma) in spacetime)

http://universe-review.ca/I15-51-string1.jpg

Depending on what you know about QFT, good point to start would be to talke a look at the Lagrangian

http://en.wikipedia.org/wiki/Polyakov_action

where a,b is \tau or \sigma, one parameter.

notice that when you don't consider a string, i.e. only tau, then this lagrangian basically is (m/2)v^2.

The Polyakov action is the classical (bosonic) Lagrangian function, you take it and implement its degrees of freedom in quantum mechanics. The quantization process.
A string has much more degrees of freedom than a point, because of its many embeddings in spacetime and so the quantum theory is richer too. A structure relevant to the string vibrations is the
http://en.wikipedia.org/wiki/Virasoro_algebra

It then turns out that this quantiation doesn't work in 4 dimensions. One way to see it is that the algebra doesn't close. For the bosonic string you'll need 26, for the ferminonic string (matter) you'll need 10. This is why we are talking about 10 dimensions here. But we observe only 3+1 so the idea is to model the world by a 3+1+6 dimensional manifold where the 6 dimensions are compactifyable in a way which doesn't kill the dynamics of the string, symmetries etc. Calabi-Yau manifolds (in this case one with 3 complex dimensions) are the way to go here.

>>3997963
my bad,
>where do you disagree
was directed at
>>3997877

>>3997969
it's 10 dimensions, one extra dimension for tricky M-theory stuff.
Since the manifolds are real, only the tangent space will be R^10. So "locally like R^10".

>>3998014
Not necessarily, because to present a clear explanation something might require either prerequisite knowledge and understanding which the student does not possess, or require a long time in order to impart that prerequisite knowledge.


If you want an explanation pitched at layman-level then watch a documentary, otherwise be prepared to put in several months or years learning about lie groups, field theory and any other gaping holes in scientific and mathematical knowledge you might have.

>ctrl f
>no one has pointed out that it looks like a bunch of underaged vaginas.

>>3998045

>>3998022
Thank you very much. Now I have a lot of stuff to read about.
You're one of the few good contributors of this board and I know to appreciate that.

if there is no \sigma, only \tau, then h_{ab} is just 1 and the action reads
T/2 int X_\mu(\tau)·X^\mu(\tau)
i.e. (m/2)v^2
(aside from the curved backgroud metric g_{\mu\nu})

>>3998058
Also notice that if you're interested in the functions X_\mu(\sigma,\tau), which are coordinate vectors in 26 dim space, you can also view X as a 26-component field in a 2-dimensional space parameterized by \sigma and \tau. This is why you'll often read the term (2-dimensional) conformal field theory in these wikipedia articles (and in the string theory papers of course).

Aside from the geometric questions regarding Calabi-Yau manifolds and whatnot, sting theory will formally look like a 2-dimensional quantum field theory. And because 2-dimensional field theories are always nice, string theory is quite nice too. I'd argue that this is the appeal. The questionable physical reality of string theory is the other side of it.

>>3998043
You're totally right. Thanks for reminding me. There's much I don't know which I still have to learn.

>>3998063
Now my mind is blown. Thanks again.

>..shape has to do with Sting Theory

>>3998073
by the no-\sigma-limit?
You haven't answered what you study or in what semester. Physics in 3rd year?

I come to /sci/ mostly because of little computations I can plug into Mathematica. And I troll a lot too.

>>3998087
>what you study or in what semester. Physics in 3rd year?
What I'm studying has nothing to do with physics. But I consider physics fucking interesting and love to learn new stuff. That's basically why I come to /sci/.

>And I troll a lot too.
Wouldn't have expected that one.

>>3998063
Right. 6, 10 or 26 dimensions of space that can be plotted in yer basic 3, or even 2 dimensions. Because we can never have too many dimensions. I'm going to make some extra dimensions right now .. with toilet paper.

>>3997749
>bullet points.

Superimposed geometry may look complex, but it's just normal shit superimposed. This painting is not some childish splatter but a Jackson Pollock. High art worth $10 million dollars.