ScalingStacks

Remark 2.3 . [00PL]

Original official author HTML, exact retained edition. Historical TeX conversion verdicts remain unchanged. Cited-edition alignment and mathematical self-containment are not assessed.

Complete original source context · Original author HTML

Remark 2.3.

Assuming an L1L^{1}-bound on ϕ\phi, then we can take a suitable cutoff function χ\chi, and via integration by parts,

∫B1−1​∂∂¯​ϕ∧ωEn−1≤∫B2χ​−1​∂∂¯​ϕ∧ωEn−1=∫B2ϕ​−1​∂∂¯​χ∧ωEn−1≤‖χ‖C2​‖ϕ‖L1≤C.\int_{B_{1}}\sqrt{-1}\partial\bar{\partial}\phi\wedge\omega_{E}^{n-1}\leq\int_{B_{2}}\chi\sqrt{-1}\partial\bar{\partial}\phi\wedge\omega_{E}^{n-1}=\int_{B_{2}}\phi\sqrt{-1}\partial\bar{\partial}\chi\wedge\omega_{E}^{n-1}\leq\left\lVert\chi\right\rVert_{C^{2}}\left\lVert\phi\right\rVert_{L^{1}}\leq C.

This simple idea is a basic version of the Chern-Levine inequality, which is another fundamental reason why psh functions are much more regular than the subharmonic functions in general dimensions.

Original mathematics by the credited authors. Source-backed reader collection; mathematical self-containment is not assessed.