Isoperimetric Functions of Amalgamations of Nilpotent Groups
نویسنده
چکیده
We consider amalgamations of nitely generated nilpotent groups of class c. We show that doubles satisfy a polynomial isoperimetric inequality of degree 2c. Generalising doubles we introduce non-twisted amalgamations and show that they satisfy a polynomial isoperimetric inequality as well. We give a su cient condition for amalgamations along abelian subgroups to be non-twisted and thereby to satisfy a polynomial isoperimetric inequality. We conclude by giving an example of a twisted amalgamation along an abelian subgroup having an exponential isoperimetric function.
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