Sigma Invariants of Direct Products of Groups
نویسنده
چکیده
The Product Conjecture for the homological Bieri-Neumann-StrebelRenz invariants is proved over a field. Under certain hypotheses the Product Conjecture is shown to also hold over Z, even though D. Schütz has recently shown that the Conjecture is false in general over Z. Our version over Z is applied in a joint paper with D. Kochloukova [5] to show that for all n Thompson’s group F contains subgroups of type Fn which are not of type FPn+1.
منابع مشابه
New Algorithm For Computing Secondary Invariants of Invariant Rings of Monomial Groups
In this paper, a new algorithm for computing secondary invariants of invariant rings of monomial groups is presented. The main idea is to compute simultaneously a truncated SAGBI-G basis and the standard invariants of the ideal generated by the set of primary invariants. The advantage of the presented algorithm lies in the fact that it is well-suited to complexity analysis and very easy to i...
متن کاملThe Sigma Invariants of the Lamplighter Groups
We compute the Bieri-Neumann-Strebel-Renz geometric invariants, Σn, of the lamplighter groups Lm by using the Diestel-Leader graph DL(m,m) to represent the Cayley graph of Lm.
متن کاملSemi-direct Products of Lie Algebras, Their Invariants and Representations
Introduction 1 1. Preliminaries 6 2. Generic stabilisers (centralisers) for the adjoint representation 9 3. Generic stabilisers for the coadjoint representation 10 4. Semi-direct products of Lie algebras and modules of covariants 12 5. Generic stabilisers and rational invariants for semi-direct products 14 6. Reductive semi-direct products and their polynomial invariants 21 7. Takiff Lie algebr...
متن کاملQuantitative Assessment of Analytical Phase Quality of Clinical Biochemistry Parameters Using Sigma Metrics
Background and Aims: Six sigma is the latest version of total quality management. It is quantitative goal for process performance. With increasing demands for improved accuracy and reliability of the results, Six Sigma is gaining increased visibility in the clinical laboratory process outcomes. The aim of study was to evaluate the quality of analytical phase performance in a clinical biochemist...
متن کاملMistake Proofing Cam Mechanism Through Six-sigma Process: Case Study on Clothes Printing Machines
Controlling the occurrence of defects is a major challenge for manufacturing organizations that are seeking to enhance their competitive position in today’s global market. This paper considers the process of screen-printing T-shirts using hydraulic and pneumatic printing machines. Several defects in the output of this printing process have been observed, especially with multi colors printing as...
متن کامل