A-infinity Structure on Ext-algebras
نویسنده
چکیده
Let A be a connected graded algebra and let E denote its Extalgebra L i Ext i A(kA, kA). There is a natural A∞-structure on E, and we prove that this structure is mainly determined by the relations of A. In particular, the coefficients of the A∞-products mn restricted to the tensor powers of ExtA(kA, kA) give the coefficients of the relations of A. We also relate the mn’s to Massey products.
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