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

Ibrahim Assem, Juan Carlos Bustamante, Diane Castonguay, Cristian Novoa


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.

Palabras clave

Fundamental groups ; Bound quivers ; Presentations of algebras.

Texto completo:



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DOI: http://dx.doi.org/10.4067/S0716-09172005000100007

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