/sci/ - Science & Math

I don't feel the subject is particular womenly, but it's not science in the sense people want to talk about here.
My uneducated suggestion would be to take a look at the names of the first semester undergrad courses in the subject (website of any university) and then check out the books, which will be named exactly after these subjects.

>>5421928
you should be able to iterate the polynomial approach to any series.
I'll give it a try.

If "even(n)" is the function for even values and "odd(n)" the funct for odd values, then

\Theta((-1)^n)·even(n)+\Theta((-1)^{n+1})·odd(n)

(\Theta being 0 for n<0 and 1 for n>0, you can also do this with smooth functions)

will always only turn on one part.

>>5062681
why not?
The theorem as such is fairly simple.
The proof idea is pretty ingenious and (the diagonal lemma) is pretty technical - but then again, using modern terminology, you can split the proof apart in graspable bits as well.

if f is T-periodic, then f's values in [0,a] are the same as in [T,T+a] and so

int_0^a = int_T^(T+a)

then

int_0^T
= int_0^T + int_T^(T+a) - int_0^a
= int_0^(T+a) - int_0^a
= int_a^(T+a)

You can do as
>>5019567
said. It's e.g. found in Peskin Schröder, around page 300.
The problem has a pretty general solution looking like
"(a·g+b·kk)/k^2"
where kk are indexed by \mu and \nu respectively and b is a linear function of \lambda.
I'm surprised that you want to compute propagators but you don't know the gauge fixing term.

To shine a little light on it:
The restriction [\partial_\mu A^\mu=0] is the associated gauge, the Lorenz gauge. It's described in the middle of the gauge fixing article on the wiki page.
The idea with the lagrangian term can be understood this way: You introduce an auxiliary "field" X (the lambda), which really is only a Lagrange multiplier, and it's "quation of motion" is just dL/dX=0, which happens to be the gauge fixing as this is the coefficient of X in the lagrangian.

More:
People do this, because the gauge degrees of freedom, the "blind angle" as I like to call it, is unphysical. There seem to be more field configurations that there really are and as a consequence, when you qunatize you get unphysical degrees of freedom.

http://en.wikipedia.org/wiki/Gupta%E2%80%93Bleuler_formalism

The Lorenz gauge (and the related R-gauges) are covariant ones, this is why you find them in the lagrangian for field theory.
In the non-abelian case, (Quantum Chromodynamics, say) this gauging away of the "blind angle" introduces new fields though, the ghosts.

http://en.wikipedia.org/wiki/Faddeev%E2%80%93Popov_ghost

>>4304713
you should ask this kind of stuff on stack exchange though. It's not like there is the scientific elite there anyway and there are hardly any practical questions on QFT.

>>4012496
You start a thread, post 5 quotes and don't want a discussion? what is it you want?

>>4012532
mhm, I kinda view philosophy of science as part of metaphysics.

>>3964587
something along the lines of..
it's linear, its continous, its continous at 0, its invertible, the complement of that domain is open?

Not in the standard model, no. Elementary particles are "elementary" because of that.

At which stage seems to be the problem, boy?

>>3712737
(continued)
The same thing happens when you define Enthalpy. You want something which is resistent to volume change, and what you end up with is the function H, which satisfies
dH=SdT+VdP
Observe that the work dW=PdV is not part of this energy quantity anymore. This is why Engineers/Hydrodynamics people fap over it. It's a measure of more or less heat only (the experimental parameter is usually kept constant, so dP=0, such that dH=dQ)
Then comes the Gibbs free energy, which gets rid of both, S AND V. So
dG naturally turns out to be
dG=-SdT-VdP.
This doesn't depend on pretty much anything (other that T and P, which you control in parameters).
But wait! We have forgotten something. There still is the parameter N, the number of particles <-- this is the origin of that one:
http://en.wikipedia.org/wiki/Gibbs%E2%80%93Duhem_equation

>>3666971
both kind of travel in a manual sense. But there are also time travel versions where they just beam around.

In star trek there are 14 or more versions of time travel. However I think it's strange to talk about dying in the context of time traveling.

And conderning spatial traveling: I'm sure Q could just shift the universes content 1 cm to the left - Everything would die!!

>>3540578
what's the problem with "Phd in math any job I want 300k starting?"
It's a response meme, it's not cancerous at all - the opposite is the case, it mocks all the /adv/, /edu/ and /eco/ threads.


>>3540731
sad owl is sad

Hey Atheists, if God doesn't exist, then why did Jesus die for our sins??

God: 1
Atheists: 0

I don't like exact sequences.
I like chaos and huge kernels, muhahaha

>>3466779
In wahrheit war der Typ im Video nur ein stunt-double und ich bin eigentlich Emma Stone - alles was du hier ließt hab ich zuerst duch nen online-translater gejagt. Ich hoffe jetzt wo du die Wahrheit weißt fühlst du dich nichtmehr betrogen.