# The Dehn functions of Out(F_n) and Aut(F_n)

@article{Bridson2010TheDF,
title={The Dehn functions of Out(F\_n) and Aut(F\_n)},
author={Martin R. Bridson and Karen Vogtmann},
journal={arXiv: Group Theory},
year={2010}
}
• Published 5 November 2010
• Mathematics
• arXiv: Group Theory
For n > 2, the Dehn functions of Aut(F_n) and Out(F_n) are exponential. Hatcher and Vogtmann proved that they are at most exponential, and the complementary lower bound in the case n=3 was established by Bridson and Vogtmann. Handel and Mosher completed the proof by reducing the lower bound for n>4 to the case n=3. In this note we give a shorter, more direct proof of this last reduction.
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