FenchelNielsenZomorrodian.Discrete.FiniteIndex

5 sections | 5 files | 18 declarations

This module develops Fenchel--Nielsen--Zomorrodian presentation reductions, period relations, reindexings, and quotient maps.

Definitions

1 files | 5 declarations | 2 Theorem | 3 Definition

The predicate records that the quotient attached to the subgroup has derived length at most the given bound.

1 files | 3 declarations | 3 Theorem

The comap of a finite-index subgroup along a homomorphism has finite index.

1 files | 2 declarations | 2 Theorem

Torsion-freeness passes to subgroups.

1 files | 6 declarations | 4 Theorem | 1 Definition | 1 Structure

Data for a smooth quotient of a Fenchel--Nielsen--Zomorrodian group.

1 files | 2 declarations | 1 Theorem | 1 Abbreviation

The finite solvable smooth quotient data package records the quotient map and its derived-length control.