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The first Hochschild (co)homology when adding arrows to a bound quiver algebra. (English) Zbl 1423.18051

The first Hochschild cohomology vector space \(HH^1(B)\) of an algebra \(B\) over a field \(k\) is isomorphic to the quotient of the \(k\)-derivations of the algebra by the inner ones. For a bound quiver algebra \(B = kQ/I\), given some hypotheses on \(I\), J. A. de la Peña and M. Saorín [Manuscr. Math. 104, No. 4, 431–442 (2001; Zbl 0985.16008)] obtained formulas computing the dimension of \(HH^1(B)\).
The authors study the change in both the Hochschild cohomology and Hochschild homology of an algebra given by quiver and relations, when arrows to the quiver are added. A main tool for the work is relative cohomology as defined by G. Hochschild [Trans. Am. Math. Soc. 82, 246–269 (1956; Zbl 0070.26903)] and used for instance by M. Auslander and Ø. Solberg [Commun. Algebra 21, No. 9, 2995–3031 (1993; Zbl 0792.16017)] in the context of representation theory. For this purpose they show that there exists a short exact sequence which relates the first cohomology vector spaces of the algebras to the first relative cohomology.
The first Hochschild homologies are isomorphic when adding new arrows. As a by-product of the presented formula, a new computation of the dimension of \(HH^1(kQ)\) for a quiver \(Q\) without cycles is obtained.

MSC:

18G25 Relative homological algebra, projective classes (category-theoretic aspects)
16E30 Homological functors on modules (Tor, Ext, etc.) in associative algebras
16E40 (Co)homology of rings and associative algebras (e.g., Hochschild, cyclic, dihedral, etc.)
18G15 Ext and Tor, generalizations, Künneth formula (category-theoretic aspects)

References:

[1] Artenstein, D.; Lanzilotta, M.; Solotar, A., Algebr. Represent. Theory, 1-36 (2019)
[2] Assem, I.; Bustamante, J. C.; Igusa, K.; Schiffler, R., The first Hochschild cohomology group of a cluster tilted algebra revisited, Internat. J. Algebra Comput., 23, 729-744 (2013) · Zbl 1279.16008
[3] Assem, I.; Redondo, M. J., The first Hochschild cohomology group of a Schurian cluster-tilted algebra, Manuscripta Math., 128, 373-388 (2009) · Zbl 1211.16007
[4] Assem, I.; Redondo, M. J.; Schiffler, R., On the first Hochschild cohomology group of a cluster-tilted algebra, Algebr. Represent. Theory, 18, 1547-1576 (2015) · Zbl 1360.16007
[5] Assem, I.; Simson, D.; Skowroński, A., Elements of the Representation Theory of Associative Algebras, vol. 1. Techniques of Representation Theory, London Mathematical Society Student Texts, vol. 65 (2006), Cambridge University Press: Cambridge University Press Cambridge · Zbl 1092.16001
[6] Auslander, M.; Solberg, Ø., Relative homology and representation theory. I. Relative homology and homologically finite subcategories, Comm. Algebra, 21, 2995-3031 (1993) · Zbl 0792.16017
[7] Buchweitz, R.-O.; Liu, S., Hochschild cohomology and representation-finite algebras, Proc. Lond. Math. Soc., 88, 355-380 (2004) · Zbl 1061.16016
[8] Cartan, H.; Eilenberg, S., Homological Algebra (1956), Princeton University Press: Princeton University Press Princeton, N. J. · Zbl 0075.24305
[9] Cibils, C., On \(H^1\) of finite dimensional algebras, (Colloquium on Homology and Representation Theory. Colloquium on Homology and Representation Theory, Vaquerías, 1998. Colloquium on Homology and Representation Theory. Colloquium on Homology and Representation Theory, Vaquerías, 1998, Bol. Acad. Nac. Cienc. (Córdoba), vol. 65 (2000)), 73-80 · Zbl 1009.16009
[10] Cibils, C.; Saorín, M., The first cohomology group of an algebra with coefficients in a bimodule, J. Algebra, 237, 121-141 (2001) · Zbl 0992.16009
[11] Cibils, C.; Marcos, E.; Redondo, M. J.; Solotar, A., Cohomology of split algebras and of trivial extensions, Glasg. Math. J., 45, 21-40 (2003) · Zbl 1052.16007
[12] Cibils, C.; Redondo, M. J.; Saorín, M., The first cohomology group of the trivial extension of a monomial algebra, J. Algebra Appl., 3, 143-159 (2004) · Zbl 1062.16013
[13] Cibils, C.; Lanzilotta, M.; Marcos, E. N.; Solotar, A., Adding or deleting arrows of a bound quiver algebra and Hochschild (co)homology · Zbl 1457.18014
[14] de la Peña, J. A.; Saorín, M., On the first Hochschild cohomology group of an algebra, Manuscripta Math., 104, 431-442 (2001) · Zbl 0985.16008
[15] Gabriel, P., Indecomposable representations. II, (Symposia Mathematica, vol. XI. Convegno di Algebra Commutativa. Symposia Mathematica, vol. XI. Convegno di Algebra Commutativa, INDAM, Rome, 1971 (1973), Academic Press: Academic Press London) · Zbl 0276.16001
[16] Gabriel, P., Auslander-Reiten sequences and representation-finite algebras, (Representation Theory, I. Representation Theory, I, Proc. Workshop, Carleton Univ., Ottawa, Ont., 1979. Representation Theory, I. Representation Theory, I, Proc. Workshop, Carleton Univ., Ottawa, Ont., 1979, Lecture Notes in Math., vol. 831 (1980), Springer: Springer Berlin) · Zbl 0445.16023
[17] Gatica, M. A.; Lanzilotta, M., Hochschild cohomology of a generalisation of canonical algebras, São Paulo J. Math. Sci., 4, 251-271 (2010) · Zbl 1243.16006
[18] Gerstenhaber, M., On the deformation of rings and algebras, Ann. of Math., 79, 59-103 (1964) · Zbl 0123.03101
[19] Green, E. L.; Psaroudakis, C.; Solberg, Ø., Reduction techniques for the finitistic dimension · Zbl 1496.16009
[20] Happel, D., Hochschild cohomology of finite dimensional algebras, (Séminaire d’Algèbre Paul Dubreil et Marie-Paul Malliavin, 39ème Année. Séminaire d’Algèbre Paul Dubreil et Marie-Paul Malliavin, 39ème Année, Paris, 1987/1988. Séminaire d’Algèbre Paul Dubreil et Marie-Paul Malliavin, 39ème Année. Séminaire d’Algèbre Paul Dubreil et Marie-Paul Malliavin, 39ème Année, Paris, 1987/1988, Lecture Notes in Math., vol. 1404 (1989), Springer: Springer Berlin), 108-126
[21] Hochschild, G., Relative homological algebra, Trans. Amer. Math. Soc., 82, 246-269 (1956) · Zbl 0070.26903
[22] Kaygun, A., Jacobi-Zariski exact sequence for Hochschild homology and cyclic (co)homology, Homology, Homotopy Appl., 14, 65-78 (2012) · Zbl 1259.19003
[23] Kaygun, A., Erratum to Jacobi-Zariski exact sequence for Hochschild homology and cyclic (co)homology, Homology, Homotopy Appl., 21, 2 (2019), in press, preprint · Zbl 1432.19002
[24] Keller, B., Hochschild cohomology and derived Picard groups, J. Pure Appl. Algebra, 190, 177-196 (2004) · Zbl 1060.16010
[25] Launois, S.; Lenagan, T. H., The first Hochschild cohomology group of quantum matrices and the quantum special linear group, J. Noncommut. Geom., 1, 281-309 (2007) · Zbl 1137.16015
[26] Le Meur, P., On maximal diagonalizable Lie subalgebras of the first Hochschild cohomology, Comm. Algebra, 38, 1325-1340 (2010) · Zbl 1238.16006
[27] Le Meur, P., Galois coverings of weakly shod algebras, Comm. Algebra, 38, 1291-1318 (2010) · Zbl 1243.16011
[28] Ringel, M., Tame Algebras and Integral Quadratic Forms, Lecture Notes in Mathematics, vol. 1099 (1984), Springer-Verlag: Springer-Verlag Berlin · Zbl 0546.16013
[29] Schiffler, R., Quiver Representations, CMS Books in Mathematics/Ouvrages de Mathématiques de la SMC (2014), Springer: Springer Cham · Zbl 1310.16015
[30] Solberg, Ø., Going relative with Maurice – a survey, (Surveys in Representation Theory of Algebras. Surveys in Representation Theory of Algebras, Contemp. Math., vol. 716 (2018), Amer. Math. Soc.: Amer. Math. Soc. Providence, RI), 155-172 · Zbl 1422.16026
[31] Strametz, C., The Lie algebra structure on the first Hochschild cohomology group of a monomial algebra, J. Algebra Appl., 5, 245-270 (2006) · Zbl 1163.16300
[32] Taillefer, R., First Hochschild cohomology group and stable equivalence classification of Morita type of some tame symmetric algebras, Homology, Homotopy Appl., 21, 19-48 (2019) · Zbl 1433.16006
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