Alexander Braverman

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Aug
18
accepted FIltrations on a vector bundle on a curve
Aug
18
comment FIltrations on a vector bundle on a curve
Thanks! This was exactly the reference I was looking for.
Aug
17
comment FIltrations on a vector bundle on a curve
No, the point is that if $E$ has rank 2 then the claim is that we can find a line subbundle $E_1$ of $E$ such that $deg(E_1)-deg(E/E_1)$ is not too small (I think you can always make it smaller than $g$ in this case) -- this is true even when the degree of $E$ is very negative.
Aug
17
revised FIltrations on a vector bundle on a curve
added 19 characters in body
Aug
16
comment FIltrations on a vector bundle on a curve
Yes, if you wish (otherwise the question is empty)
Aug
16
comment FIltrations on a vector bundle on a curve
Well, it has something to do with Harder-Narasimhan, but it is not quite that. For example, if $n=2$ then the statement is that any rank 2 bundle has a line sub-bundle whose degree is not too small.
Aug
16
asked FIltrations on a vector bundle on a curve
Aug
16
accepted A question on non-archimedian Fourier transform
Aug
16
answered A question on non-archimedian Fourier transform
Aug
14
comment Quasi-affineness of the base of a $\mathbb{G}_a$-torsor
Actually, I suspect that the answer might be yes, if you assume that $Y$ is separated.
Aug
14
comment A question on non-archimedian Fourier transform
By nilcone he actually means degenerate matrices, but there is one point in his proof that I don't understand.
Aug
14
comment A question on non-archimedian Fourier transform
Actually I don't understand why the center of $Mp(2)$ acts non-trivially in this representation.
Aug
14
comment A question on non-archimedian Fourier transform
OK, I agree (about the invariance of the condition - I just made a stupid computational mistake). Well, in this case we seem to have a contradition in mathematics, since I also don't see any flaw in Roman's argument (which shows that such a distribution can't exist...).
Aug
14
comment A question on non-archimedian Fourier transform
Actually, I think that the equation $\psi(AXB)=|\det(A)\det(B)|^{-1}\psi(X)$ is not invariant under the Fourier transform. Am I wrong?
Aug
14
comment A question on non-archimedian Fourier transform
Below Semyon claims that there is a distribution on degenerate matrices whose FT is concentrated there as well, but so far I don't understand all the details.
Aug
14
comment A question on non-archimedian Fourier transform
Yes, sure, I got confused too about something. Semyon, why is this distribution unique?
Aug
14
comment A question on non-archimedian Fourier transform
I didn't understand the last argument - on what space does the group Mp(2) act?
Aug
12
comment A question on non-archimedian Fourier transform
Semyon, I need compacts support but in the non-archimedian case there should be no difference. Let me try to understand your distribution.
Aug
12
revised A question on non-archimedian Fourier transform
added 121 characters in body
Aug
12
comment A question on non-archimedian Fourier transform
No, there is only a map from $\mathcal S^0$ to $\mathcal S$ (since both are spaces of compactly supported functions, there is no map in the opposite direction). You can think of $\mathcal S^0$ as the subspace of $\mathcal S$ consisting of functions which vanish on degenerate matrices.