Abstract
We study Morita rings \(\Lambda _{(\phi ,\psi )}=\left (\begin {array}{cc}A &_{A}N_{B} \\ _{B}M_{A} & B \end {array}\right )\) in the context of Artin algebras from various perspectives. First we study covariantly finite, contravariantly finite, and functorially finite subcategories of the module category of a Morita ring when the bimodule homomorphisms \(\phi \) and \(\psi \) are zero. Further we give bounds for the global dimension of a Morita ring \(\Lambda _{(0,0)}\), as an Artin algebra, in terms of the global dimensions of A and B in the case when both \(\phi \) and \(\psi \) are zero. We illustrate our bounds with some examples. Finally we investigate when a Morita ring is a Gorenstein Artin algebra and then we determine all the Gorenstein-projective modules over the Morita ring \(\Lambda _{\phi ,\psi }\) in case \(A=N=M=B\) and A an Artin algebra.
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Presented by Jon F. Carlson.
The second author has been co-financed by the European Union (European Social Fund - ESF) and Greek national funds through the Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) - Research Funding Program: Heracleitus II. Investing in knowledge society through the European Social Fund.
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Green, E.L., Psaroudakis, C. On Artin Algebras Arising from Morita Contexts. Algebr Represent Theor 17, 1485–1525 (2014). https://doi.org/10.1007/s10468-013-9457-4
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DOI: https://doi.org/10.1007/s10468-013-9457-4
Keywords
- Morita rings
- Functorially finite subcategories
- Global dimension
- Gorenstein Artin algebras
- Gorenstein-projective modules