A-classification of map-germs via $_V$K-equivalence

Kevin Houston; Roberta Wik Atique

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arXiv · 1302.1104

A-classification of map-germs via $_V$K-equivalence

Kevin Houston·Roberta Wik Atique

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Abstract

The classification of map-germs up to the natural right-left equivalence (also known as A-equivalence) is often complicated. Certainly it is more complicated than K-equivalence which is extremely easy to work with because the associated tangent spaces are not 'mixed' modules as they are in the A-equivalence case. In this paper we use a version of K-equivalence, denoted $_V$K-equivalence, that is defined using K-equivalences that preserve a variety in the source of maps to classify maps up to A-equivalence. This is possible through making clear the connection between the two equivalences - previous work by Damon mostly focussed on the relation between the codimensions associated to the maps. To demonstrate the power and efficiency of the method we give a classification of certain A$_e$-codimension 2 maps from $n$-space to $n+1$-space. The proof using $_V$K-equivalence is considerably shorter - by a wide margin - than one using A-equivalence directly.

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Kevin Houston, Roberta Wik Atique. 2013-02-05. A-classification of map-germs via $_V$K-equivalence. https://arxiv.org/abs/1302.1104

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