Abstract

Let R be the pullback of two surjective homomorphisms of algebras A → B and C → B. Here we consider a particular class, the so-called linearly oriented pullback, where the injective and projective R-modules can be determined by those ones over A and C. For this class of pullbacks, we study the relationship between the left and the right parts of the category of modules (see Happel et al. 13) over the involved algebras in order to find relationships between some classes of these algebras.

中文翻译：

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关于线性定向的拉回和代数类

摘要

令R为代数A → B和C → B的两个射影同态的回拉。在这里，我们考虑一类特殊的东西，即所谓的线性定向回拉，其中射入和射出的R模可以由A和C上的那些确定。对于此类回调，我们研究了所涉及代数上模块类别的左部分和右部分之间的关系（请参阅Happel等人13），以找到这些代数的某些类之间的关系。