Let $ S $ be a commutative Noetherian ring and $ \mathfrak{a} $ a proper ideal of $ S $. We give several bounds of $ \mathfrak{a} $-depth of $ S $-complexes and $ S $-modules, investigate the behavior of $ \mathfrak{a} $-depth and $ \mathfrak{a} $-Cohen-Macaulay modules under tensor product with a faithfully flat $ S $-module. Furthermore, we establish the Foxby equivalence of $ \mathfrak{a} $-Cohen-Macaulay $ S $-modules.
Citation: Pengju Ma, Yanjie Li. $ \mathfrak{a} $-Depth and $ \mathfrak{a} $-Cohen-Macaulay modules[J]. Electronic Research Archive, 2026, 34(2): 1195-1208. doi: 10.3934/era.2026055
Let $ S $ be a commutative Noetherian ring and $ \mathfrak{a} $ a proper ideal of $ S $. We give several bounds of $ \mathfrak{a} $-depth of $ S $-complexes and $ S $-modules, investigate the behavior of $ \mathfrak{a} $-depth and $ \mathfrak{a} $-Cohen-Macaulay modules under tensor product with a faithfully flat $ S $-module. Furthermore, we establish the Foxby equivalence of $ \mathfrak{a} $-Cohen-Macaulay $ S $-modules.
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