0 On our paper ‘ Almost Free Splitter ’ , a correction
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چکیده
Let R be a subring of Q and recall from [3] that an R-module G is a splitter if ExtR(G,G) = 0. We correct the statement of Main Theorem 1.5 in [3]. Assuming CH any א1-free splitter of cardinality א1 is free over its nucleus as shown in [3]. Generally these modules are very close to being free as explained below. This change follows from [3] and is due to an incomplete proof (noticed thanks to Paul Eklof) in [3, first section on p. 207]. Assuming the negation of CH, in [6] it will be shown that under Martin’s axiom these splitters are free indeed. However there are models of set theory having non-free א1-free splitter of cardinality א1.
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تاریخ انتشار 2000