The dimensions of the homomorphism spaces to indecomposable modules over the four subspace algebra

2012/07/09 by Andrzej Mróz, Mróz, Andrzej
Mathematics · #14L30 #16G60 #16G70 #68Q99 #FOS: Mathematics #Representation Theory (math.RT) #Rings and Algebras (math.RA) #math.RA #math.RT #msc:14L30 #msc:16G60 #msc:16G70 #msc:68Q99

paper · pdf · doi:10.48550/arxiv.1207.2081

arxiv created 2012/07/09 · arxiv updated 2012/07/10

Abstract

This is the addendum to the paper "On the Multiplicity Problem and the Isomorphism Problem for the Four Subspace Algebra" Communications in Algebra, 40:6 (2012), 2005-2036 (DOI: 10.1080/00927872.2011.570830). We give here the full proof of Proposition 3.3, describing the formulas for the dimensions of the homomorphism spaces to indecomposable modules over the four subspace algebra Λ. The reader can also find here the full description of indecomposable Λ-modules.

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