Inversion of adjunction for quotient singularities II: Non-linear actions

TL;DR

This paper extends the inversion of adjunction formula to non-linear group actions on quotient singularities and demonstrates the semi-continuity of minimal log discrepancies for hyperquotient singularities.

Contribution

It generalizes previous results to non-linear actions, providing a more comprehensive understanding of quotient singularities and their invariants.

Findings

Proved the inversion of adjunction formula for non-linear quotient singularities.

Established semi-continuity of minimal log discrepancies for hyperquotient singularities.

Extended previous linear action results to non-linear group actions.

Abstract

We prove the precise inversion of adjunction formula for quotient singularities. As an application, we prove the semi-continuity of minimal log discrepancies for hyperquotient singularities. This paper is a continuation of arXiv:2011.07300, and we generalize the previous results to non-linear group actions.