Uniformly bounded orthonormal sections of positive line bundles on complex manifolds

Abstract

We show the existence of uniformly bounded sequences of increasing numbers of orthonormal sections of powers $L^k$ of a positive holomorphic line bundle $L$ on a compact K\"ahler manifold $M$. In particular, we construct for each positive integer $k$, orthonormal sections $s^k_1,\dots,s^k_{n_k}$ in $H^0(M,L^k)$, $n_k\ge\beta\dim H^0(M,L^k)$, such that $\{s^k_j\}$ is a uniformly bounded family, where $\beta$ is an explicit positive constant depending only on the dimension of $M$. For $m=1$, we can take $\beta=.99564$.