bio | website | front.math.ucdavis.edu/… |
---|---|---|
location | Cornell | |
age | 44 | |
visits | member for | 4 years, 10 months |
seen | 16 mins ago | |
stats | profile views | 9,652 |
Math professor at Cornell,
PhD 1996
Aug 17 |
awarded | Nice Answer |
Aug 13 |
comment |
A special Lie subalgebra
I presume $add(x)$ means $ad(x)$? |
Aug 11 |
answered | “Mathematics talk” for five year olds |
Aug 11 |
comment |
A question on non-archimedian Fourier transform
I would ordinarily think of a map $\mathcal S\to \mathcal S^0$, but you're regarding $\mathcal S^0$ as a subspace of $\mathcal S$. Is this by taking functions on $M(n)$ supported inside $GL(n)$, or is it by using the inner product somehow? |
Aug 11 |
awarded | Nice Answer |
Aug 11 |
revised |
Quotients by the additive group $\mathbb G_a$
added 31 characters in body |
Aug 10 |
comment |
Quotients by the additive group $\mathbb G_a$
Fixed. $\ \ \ \ \ \ \ \ $ |
Aug 10 |
revised |
Quotients by the additive group $\mathbb G_a$
edited body |
Aug 10 |
comment |
The target of a finite morphism $f$ is a dense open in $S$, can you extend $f$ to have target $S$?
A little more concretely: consider the sheaf of functions on $X$ that are integral over the subring of functions pulled back from $S$. Does the global $Spec$ of this sheaf of subrings give a $Y$? |
Aug 9 |
answered | Quotients by the additive group $\mathbb G_a$ |
Aug 9 |
revised |
Quotients by the additive group $\mathbb G_a$
fixed ldots |
Aug 6 |
comment |
When is $(q^k-1)/(q-1)$ a perfect square?
Finite projective space, not plane, I would say. |
Jul 31 |
comment |
Isomorphic Dual and Conjugate Representations of a Lie Algebra
Check it once and for all for the Lie algebra $End(V)$ itself. I'm voting to close as not research-level. |
Jul 29 |
comment |
Poisson ideals vs. ideals generated by Poisson central elements
Okay, so the group-action analogue is that a $G$-invariant subvariety may fail to be the intersection of a number of $G$-invariant hypersurfaces. |
Jul 29 |
answered | Horn's inequalities for n matrices |
Jul 29 |
accepted | Poisson ideals vs. ideals generated by Poisson central elements |
Jul 29 |
asked | Poisson ideals vs. ideals generated by Poisson central elements |
Jul 27 |
comment |
Are shortest halving curves simple closed geodesics?
I think this calculus of variations perspective makes clear that the more natural question is about curves with a fixed area to one side, where the area on the other side may be different (and even infinite). |
Jul 25 |
comment |
Why do Lie algebras pop up, from a categorical point of view?
The derivations of an algebra form a Lie algebra. |
Jul 24 |
comment |
Theorems for nothing (and the proofs for free)
Finite division rings commute. |