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Jun
10
comment Basis of $\mathbb{Q}[\sqrt[3]{2}]$
Can you express any element of the ring as a linear combination of those three? Are succesive values of $2^{1/3}$ contained in the ring?
Jun
10
comment The shortest path in a metric space with a given metric
@SiXUlm Have in mind what Alex said. The above is only valid for manifolds with a differentiable structure. Those are the easiest to visualize though, so you should start with them.
Jun
9
comment Continuous homorphisms between topological groups.
The main difference with topological continuity is that this (the one you expose) only requires to be so for neighbourhoods of the identity of the group. That is a big difference.
Jun
9
answered The shortest path in a metric space with a given metric
Jun
8
revised How to find $E[X^2]$ when computing the variance?
added 6 characters in body
Jun
6
comment Coordinates on the sphere not global?
It's hard to say. Could you give the source of the book? In principle the only two points on the sphere with coordinates not entirely defined are the poles, for which there is no well defined longitude.
Jun
6
revised how to know in which range $\cos^{2}\theta $ $\le$ $\sin^{2}\theta$?
added 56 characters in body
Jun
6
comment how to know in which range $\cos^{2}\theta $ $\le$ $\sin^{2}\theta$?
@Sten Thanks for pointing out!
Jun
6
answered how to know in which range $\cos^{2}\theta $ $\le$ $\sin^{2}\theta$?
Jun
6
revised general term of a given sequence
formated
Jun
6
comment How to prove that the Kronecker delta is the unique isotropic tensor of order 2?
wow, whole answer in math mode :D
Jun
3
revised proving the Klein 4 group is abelian
added 2 characters in body
May
12
awarded  Inquisitive
May
11
comment How to do this integral.
@DanielFischer I edited the question with info about the original integral and result.
May
11
revised How to do this integral.
added 606 characters in body
May
11
comment How to do this integral.
@DanielFischer That I understand. I don't understand though how can a delta function appear from that expression.
May
11
comment How to do this integral.
@DanielFischer Sorry for the lack of information. $k$ and $p$ are real, I've seen this integral in physics (in quantum field theory). What they do if shift $k$ into the complex plane by adding $\epsilon i$ to it so it can be done. I need to know how it can be done in that case. So we can consider that $\Im k>0$. Btw the solution I have is something of the form $a+b$, where $b$ has a $\delta$ function.
May
11
asked How to do this integral.
May
6
comment Check if $n=m^2$ in $\mathbb F_q$
@Engloutie right, thank you
May
6
comment Check if $n=m^2$ in $\mathbb F_q$
Thank you for the answer