4,780 reputation
21030
bio website sites.google.com/site/…
location
age
visits member for 3 years, 9 months
seen 4 hours ago

no mods no masters


17h
comment When is the rank of a general tensor 1?
Your modules $M,N$ are free over $\mathbb{Z}$ (since they have bases), so this holds if and only if the rank of one of $M$ and $N$ is one. Start by showing that $e_1\otimes f_1+e_2\otimes f_2$ can't be expressed as a pure tensor.
17h
reviewed Approve suggested edit on Limit of a function with rational numbers
Oct
21
reviewed Approve suggested edit on $ABCD $ is cyclic quadrilateral.The side $AB$ is extended to $E$ .In such a way that $BE =BC$
Oct
20
comment Infinite group not isomorphic to proper subgroup
@Krijn yes, co-Hopfian - my mistake.
Oct
20
comment Infinite group not isomorphic to proper subgroup
Such a group is called Hopfian, see en.wikipedia.org/wiki/Hopfian_group
Oct
20
reviewed Approve suggested edit on Integral of rational function with higher degree in numerator
Oct
17
reviewed Approve suggested edit on An open connected subset of compact metric connected and locally connected space, is path connected
Oct
17
reviewed Approve suggested edit on alternative solution for $\dim R[T]\geq\dim R+1$.
Oct
16
comment Lie algebras and the Killing form.
That isn't the sense in which "dual basis" is being used here. By the "dual basis" to the $x_i$ wrt $K$ they literally mean a basis $y_i$ of $g$ such that $K(x_i,y_j)=\delta_{ij}$. It's not necessary to think about the dual space at all, although as other people pointed out there is a connection.
Oct
16
comment Two Dimensional Lie Algebra
The book is by Karin Erdmann and Mark Wildon.
Oct
13
reviewed Approve suggested edit on Direct computation of hyperboloid-line intersection in 3d
Oct
10
reviewed Approve suggested edit on vector field distance
Oct
10
reviewed Approve suggested edit on Showing “$30$ divides $n^5-n$ for all $n\in\Bbb N$” using induction
Oct
9
reviewed Approve suggested edit on Calculating invariant for T shape tetrominos on rectangular board
Oct
9
reviewed Approve suggested edit on Each of two circles of equal radii with centres at A and B are pass through the center of another.
Oct
7
reviewed Approve suggested edit on commutant of a c* cubalgebra of B(H)
Oct
7
reviewed Approve suggested edit on pointwise $\implies$ uniform? (Dini's theorem)
Oct
5
comment Tensoring $k[x] \otimes_k k[y]$
$y\otimes x \notin k[x]\otimes k[y]!$
Oct
4
reviewed Reject suggested edit on circles and grid points
Oct
4
comment Déterminer l'équation de la tangente à la courbe C, parallèle à la droite d
@ClaudeLeibovici since not everyone can write English, and since there are a large number of MSE users willing to translate non-English questions, I think (as the top-voted post on my link suggested) we ought to welcome translateable non-English posts.