Fixed Subgroups are not Compressed in Direct Products of Surface Groups

Abstract

By constructing counterexamples, the authors show that the fixed subgroups are not compressed in direct products of free and surface groups, and hence negate a conjecture in [Zhang, Q., Ventura, E. and J. Wu, Fixed subgroups are compressed in surface groups, Internat. J. Algebra Comput., 25, 2015, 865–887].

Keywords

Fixed subgroup / Free group / Surface group / Direct product / Inertia / Compression / 20F65 / 20F34 / 57M07

References

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