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arXiv · 2112.09643

Weak diamond, weak projectivity, and transfinite extensions of simple artinian rings

Jan Trlifaj
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Abstract

We apply set-theoretic methods to study projective modules and their generalizations over transfinite extensions of simple artinian rings R. When R is hereditary and of cardinality at most $2^\omega$, we prove that the Weak Diamond and CH imply that projectivity of an arbitrary module can be tested at the layer epimorphisms of R.

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Jan Trlifaj. 2021-12-17. Weak diamond, weak projectivity, and transfinite extensions of simple artinian rings. https://arxiv.org/abs/2112.09643

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