3,821 reputation
1427
bio website math.cornell.edu/m/People/…
location Cornell University
age 24
visits member for 1 year, 3 months
seen yesterday

Grad student at Cornell.


Sep
1
reviewed Approve suggested edit on Is $\mathbb N$ dense in $\mathbb R$?
Sep
1
revised What is the use of scheme theory?
added 245 characters in body
Sep
1
revised What is the use of scheme theory?
added 184 characters in body
Sep
1
answered What is the use of scheme theory?
Aug
18
answered Showing $U\otimes (V\oplus W) \cong U\otimes V \oplus U\otimes W $
Aug
17
answered Standard Notation For The Set of All the Morphisms Of A Category
Aug
17
revised Use the universal cover to prove $\gamma * \gamma$ is nullhomotopic if $\gamma$ is a loop in the projective plane
added 52 characters in body
Aug
17
answered Use the universal cover to prove $\gamma * \gamma$ is nullhomotopic if $\gamma$ is a loop in the projective plane
Aug
13
reviewed No Action Needed Pre- calculus and calculus practice questions
Aug
13
awarded  Custodian
Aug
13
reviewed Close A continuous function on the real line such that the preimage of every point is either empty of has exactly 3 points
Aug
13
reviewed Close Calculation, disc in $\mathbb{C}$
Aug
13
revised Nil radical of an ideal on a commutative ring
added 6 characters in body
Aug
13
comment Nil radical of an ideal on a commutative ring
Yes, I mean that $ab\notin N(J)$. Sorry, it was just a typo.
Aug
13
answered Nil radical of an ideal on a commutative ring
Aug
12
comment Showing the Weyl algebra is simple.
It's not very advanced. This is (more or less) what you would do anyways. But it is much more clear (to me) what is going on when I am thinking of this as differential operators)
Aug
12
comment Reference request: About some important result in a book of Lefschetz.
Why do you need the main results of necessarily this book? What are the results you are looking for?
Aug
12
revised Showing the Weyl algebra is simple.
added 7 characters in body
Aug
12
answered Showing the Weyl algebra is simple.
Aug
5
comment Root space question
No, roots don't have the same value for all elements of the Cartan! By definition, an element $g\neq 0$ is in $\mathfrak{g}_\alpha$ iff $[h,g]=\alpha(h)g$. Consider example of $sl_2$. Then Cartan is $1$-dimensional, it's spanned by the diagonal matrices $diag(a,-a)$. Then if you take this $h=diag(a,-a)\in\mathfrak{h}$ and compute $[h,g]$ for $g=\begin{pmatrix}0 & 1\\ 0 & 0\end{pmatrix}$, you will get $[h,g]=a\cdot g$. This means that there is a root $\alpha$ sending $h=diag(a,-a)$ to $a$. Sure this value is different for different $a$!