A note on the fundamental group of a one-point extension

Authors

  • Ibrahim Assem Université de Sherbrooke.
  • Juan Carlos Bustamante Université de Sherbrooke.
  • Diane Castonguay Universidade Federal de Goiás.
  • Cristian Novoa Bustos Universidade Católica de Goiás.

DOI:

https://doi.org/10.4067/S0716-09172005000100007

Keywords:

Fundamental groups, Bound quivers, Presentations of algebras.

Abstract

In this note, we consider an algebra A which is a one-point extension of another algebra B and we study the morphism of fundamental groups induced by the inclusion of (the bound quiver of ) B into (that of ) A. Our main result says that the cokernel of this morphism is a free group and we prove some consequences from this fact.

Author Biographies

Ibrahim Assem, Université de Sherbrooke.

Département de Mathématiques.

Juan Carlos Bustamante, Université de Sherbrooke.

Département de Mathématiques.

Diane Castonguay, Universidade Federal de Goiás.

Instituto de Informática.

Cristian Novoa Bustos, Universidade Católica de Goiás.

Departameto de Matemática e Física.

References

[1] I. Assem, D. Castonguay, E. N. Marcos, and S. Trepode. Schurian strongly simply connected algebras and multiplicative bases. J. Algebra, 283 : pp. 161—189, (2005).

[2] I. Assem and J.A. de la Peña. The fundamental groups of a triangular algebra. Comm. Algebra, 24 (1) : pp. 187—208, (1996).

[3] K. Bongartz and P. Gabriel. Covering spaces in representation theory. Invent. Math, 65 (3) : pp. 331—378, (1981)-(1982).

[4] M. J. Bardzell and E. N. Marcos. H1(?) and presentations of finite dimensional algebras. Number 224 in Lecture Notes in Pure and Applied Mathematics, pages 31—38. Marcel Dekker, (2001).

[5] J. C. Bustamante. On the fundamental group of a schurian algebra. Comm. Algebra, 30 (11) : pp. 5305—5327, (2002).

[6] J. C. Bustamante. The classifying space of a bound quiver. J. Algebra, 277 : pp. 431—455, (2004).

[7] R. Martínez-Villa and J.A. de la Peña. The universal cover of a quiver with relations. J. Pure Appl. Algebra, 30 : pp. 873—887, (1983).

[8] A. Skowronski. Simply connected algebras and Hochschild cohomologies. In Proceedings of the sixth international conference on representation of algebras, number 14 in Ottawa-Carleton Math. Lecture Notes Ser., pp. 431—448, Ottawa, ON, (1992).

Published

2017-04-20

How to Cite

[1]
I. Assem, J. C. Bustamante, D. Castonguay, and C. Novoa Bustos, “A note on the fundamental group of a one-point extension”, Proyecciones (Antofagasta, On line), vol. 24, no. 1, pp. 79-87, Apr. 2017.

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