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I-automorphism
From Groupprops
This article defines a property that can be evaluated for an automorphism of an algebra in a variety of algebras. The evaluation of that property depends on the ambient variety, and not just on the automorphism or the algebra.
View all such properties
Contents |
Definition
Suppose
is a variety of algebras, and A is an algebra in
. An I-automorphism of A is an automorphism that can be expressed as:
where
are fixed, and
is a word in terms of the operations of the algebra,with the property that for any algebra B of
, and any choice of values
, the map:
gives an automorphism of B.
In other words
is guaranteed to give an automorphism.
Particular cases
For groups
In the variety of groups, the I-automorphisms are precisely the inner automorphisms: the automorphisms of the form
. For full proof, refer: Inner automorphisms are I-automorphisms in variety of groups
Relation with other properties
Weaker properties
| Stronger than | Formula automorphism +, and Variety-extensible automorphism + |

