2014/08/17 by Bhatnagar, Anupam
#14L30 #Algebraic Geometry (math.AG) #Dynamical Systems (math.DS) #FOS: Mathematics
paper · doi:10.48550/arxiv.1408.3846
A rational map ϕ: ℙ1 → ℙ1 along with an ordered list of fixed and critical points is called a totally marked rational map. The space of totally marked degree two rational maps, Rattm2 can be parametrized by an affine open subset of (ℙ1)5. We consider the natural action of SL2 on Rattm2 induced from the action of SL2 on (ℙ1)5 and prove that the quotient space Rattm2/SL2 exists as a scheme. The quotient is isomorphic to a Del Pezzo surface with the isomorphism being defined over ℤ[1/2].