bio  website  iazd.unihannover.de/… 

location  Hanover, Germany  
age  29  
visits  member for  4 years, 11 months 
seen  1 hour ago  
stats  profile views  2,376 
I am a postdoc at the Leibniz UniversitÃ¤t Hannover. I specialise in arithmetic geometry, algebraic number theory and analytic number theory.
8h

asked  Relative Picard functor for the Zariski topology 
Mar 23 
revised 
Twists of projective automorphisms
deleted 9 characters in body 
Mar 20 
comment 
Twists of projective automorphisms
I mean those $\sigma \in \mathrm{Aut} X$ such that $\sigma^*L \cong L$. Certainly I want $\mathrm{Aut}(\mathbb{P}^n, \mathcal{O}(1) )$ to be $\mathrm{PGL}_{n+1}$. 
Mar 20 
asked  Twists of projective automorphisms 
Mar 17 
revised 
Obstruction and rational points on curves
added 23 characters in body 
Mar 17 
answered  Obstruction and rational points on curves 
Mar 16 
comment 
Number of solutions of arithmetic function's equation
There is no asymptotic formula for $\omega(x)$; instead one knows that its maximal order is equal to what you claim. Anyway, one easily sees using the PNT that $2\pi(x)  \pi(2x) \sim 2 (\log 2) x/(\log x)^2$, which proves that there are only finitely many such $x$ satisfying your equation. 
Mar 16 
comment 
zeta function of abelian varieties and the exterior algebra
math.stackexchange.com/questions/137951/… 
Mar 11 
comment 
Unramified extensions of a given degree
If $K$ is a local field, then there exists a unique unramified extension of each degree. See Serre's book on local fields. 
Mar 6 
comment 
Variety acquiring rational point over any quadratic extension
For some classes of varieties one can prove that this cannot happen. For example, if a smooth cubic hypersurface over $\mathbb{Q}$ has a point over a single quadratic extension of $\mathbb{Q}$, then it already has a point over $\mathbb{Q}$. 
Mar 4 
comment 
A reference for $\mathbb{A}^1_R$ being a coarse moduli space of the stack of elliptic curves
I don't have it with me, so I'm not sure if it's in there, but have you tried looking in Katz, Mazur  Arithmetic Moduli of Elliptic Curves ? 
Feb 18 
comment 
Automorphisms of generic complete intersections
Thanks for the answer, but I think you have misunderstood the problem. I'm ultimately trying to show that $\sigma^*$ can't be the identity when $\sigma$ is nontrivial. So I have no idea how to handle this first case! The second case you mention is fine for me. 
Feb 18 
revised 
Automorphisms of generic complete intersections
deleted 1 character in body 
Feb 11 
comment 
automorphism group of a function field
Have you looked at what happens for $\mathbb{F}_2(t)$? 
Feb 10 
revised 
Automorphisms of generic complete intersections
added 2 characters in body 
Feb 8 
comment 
Automorphisms of generic complete intersections
Are you referring to the case of quartic surfaces? I have avoided these by assuming that $n \geq 3$ (my $n$ is the dimension of $X$, not the dimension of the ambient projective space). 
Feb 8 
asked  Automorphisms of generic complete intersections 
Feb 4 
comment 
Is there a Poisson Summation formula for imprimitive Dirichlet characters?
It would help greatly if you stated which version of the Poisson summation formula for primitive characters you are referring to. 
Jan 29 
revised 
Automorphisms of ideals of $\mathbb{C}[t]$
edited tags 
Jan 29 
comment 
cohomological obstructions and rational points
There are other obstructions than the BrauerManin obstruction, such as the étale BrauerManin obstruction, which is in general a finer obstruction. 