Toward Abhyankar's Inertia Conjecture for PSL_2(\ell)
arXiv:1010.2819
Abstract
For \ell \neq p odd primes, we examine PSL_2(\ell)-covers of the projective line branched at one point over an algebraically closed field of characteristic p, where PSL_2(\ell) has order divisible by p. We show that such covers can be realized with a large variety of inertia groups. Furthermore, for each inertia group realized, we can realize all "sufficiently large" higher ramification filtrations.
Final version, now 12 pages