Cancellation properties in ideal systems: A classification of $\boldsymbol{e.a.b.}$ semistar operations

Marco Fontana; K. Alan Loper

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arXiv · 0905.0217

Cancellation properties in ideal systems: A classification of $\boldsymbol{e.a.b.}$ semistar operations

Marco Fontana·K. Alan Loper

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Abstract

We give a classification of {\texttt{e.a.b.}} semistar (and star) operations by defining four different (successively smaller) distinguished classes. Then, using a standard notion of equivalence of semistar (and star) operations to partition the collection of all {\texttt{e.a.b.}} semistar (or star) operations, we show that there is exactly one operation of finite type in each equivalence class and that this operation has a range of nice properties. We give examples to demonstrate that the four classes of {\texttt{e.a.b.}} semistar (or star) operations we defined can all be distinct. In particular, we solve the open problem of showing that {\texttt{a.b.}} is really a stronger condition than {\texttt{e.a.b.}}

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BibTeX RIS

Marco Fontana, K. Alan Loper. 2009-05-02. Cancellation properties in ideal systems: A classification of $\boldsymbol{e.a.b.}$ semistar operations. https://arxiv.org/abs/0905.0217

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