activity
20242026
collaborators

5 papers

math.AG2026

Characterization of distinguished matrices of isolated hypersurface singularities through their spectral numbers

Sven Balnojan, Claus Hertling

Isolated hypersurface singularities come equipped with distinguished bases of their Milnor lattices and with upper triangular integral matrices, which are called here distinguished…

math.RA2026

Conjugacy classes of regular integer matrices

Claus Hertling, Khadija Larabi

This paper is devoted to the theory of -conjugacy classes of regular integer matrices. Such a matrix is -conjugate to the companio…

math.RA2026

Semigroups from full lattices in commutative -algebras

Claus Hertling, Khadija Larabi

The full lattices in a finite dimensional commutative -algebra form a commutative semigroup. In the case of an algebraic number field the top part of a certain quotien…

math.NT2025

Odd vanishing cycles in cyclotomic fields

Claus Hertling, Khadija Larabi

A cusp of a Hecke group has two natural lifts to the ring of integers of a cyclotomic field. These lifts are called here odd vanishing cycles. All lifts of all cusps together…

math.AG2024

Unimodular bilinear lattices, automorphism groups, vanishing cycles, monodromy groups, distinguished bases, braid group actions and moduli spaces from upper triangular matrices

Claus Hertling, Khadija Larabi

This monograph starts with an upper triangular matrix with integer entries and 1's on the diagonal. It develops from this a spectrum of structures, which appear in different contex…