Problems / algebra
algebra / Birational geometry; pluricanonical systems
The effective Iitaka fibration conjecture
Theorem 1.1: for each d≥1 there is m(d)>0 such that, over every algebraically closed field of characteristic zero, ∣m(d)KX∣ is nonempty and its section ratios generate the Iitaka function field for every smooth integral projective d-fold with κ(X)≥0; every multiple of m(d) works too. Theorem 1.2 gives a uniform a(d,Φ) with a(KX+B)∼0 for projective lc pairs with KX+B∼Q0 and coefficients in a DCC set Φ. The bound m(d) is existential; no explicit value is given.