TY - JOUR
T1 - On the category of weak Cayley table morphisms between groups
AU - Johnson, K. W.
AU - Smith, J. D.H.
N1 - Copyright:
Copyright 2007 Elsevier B.V., All rights reserved.
PY - 2007/3
Y1 - 2007/3
N2 - Weak Cayley table functions between groups are generalized conjugacy-preserving homomorphisms, under which products of images are conjugate to images of products. There is a weak Cayley table bijection between two groups iff they have the same 2-characters. In this paper, weak Cayley table functions are augmented to include the specific conjugating elements, leading to the concept of a weak (Cayley table) morphism. If the conjugating elements are chosen subject to a crossed-product condition, then the weak morphisms between groups form a category. The forgetful functor to this category from the category of group homomorphisms is shown to possess a left adjoint. Two weak morphisms are said to be homotopic if they project to the same weak Cayley table function. As a first step in the analysis of the category of weak morphisms, the group of units of the monoid of weak morphisms homotopic to the identity automorphism of a group is described.
AB - Weak Cayley table functions between groups are generalized conjugacy-preserving homomorphisms, under which products of images are conjugate to images of products. There is a weak Cayley table bijection between two groups iff they have the same 2-characters. In this paper, weak Cayley table functions are augmented to include the specific conjugating elements, leading to the concept of a weak (Cayley table) morphism. If the conjugating elements are chosen subject to a crossed-product condition, then the weak morphisms between groups form a category. The forgetful functor to this category from the category of group homomorphisms is shown to possess a left adjoint. Two weak morphisms are said to be homotopic if they project to the same weak Cayley table function. As a first step in the analysis of the category of weak morphisms, the group of units of the monoid of weak morphisms homotopic to the identity automorphism of a group is described.
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U2 - 10.1007/s00029-007-0032-x
DO - 10.1007/s00029-007-0032-x
M3 - Article
AN - SCOPUS:34249097748
SN - 1022-1824
VL - 13
SP - 57
EP - 67
JO - Selecta Mathematica, New Series
JF - Selecta Mathematica, New Series
IS - 1
ER -