New paper accepted by Journal of Algebra

New paper by Evgeny Khukhro (Univ. of Lincoln) and Wolfgang Moens† (University of Vienna) “Fitting height of finite groups admitting a fixed-point-free automorphism satisfying an additional polynomial identity” has been accepted for publication in Journal of Algebra.

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†The second author died in May 2022.

Abstract: Let $f(x)$ be a non-zero polynomial with integer coefficients. An automorphism $\varphi$ of a group $G$ is said to satisfy the elementary abelian identity $f(x)$ if the linear transformation induced by $\varphi$ on every characteristic elementary abelian section of $G$ is annihilated by $f(x)$ . We prove that if a finite (soluble) group $G$ admits a fixed-point-free automorphism $\varphi$ satisfying an elementary abelian identity $f(x)$ , where $f(x)$ is a primitive polynomial, then the Fitting height of $G$ is bounded in terms of $\deg(f(x))$ . We also prove that if $f(x)$ is any non-zero polynomial and $G$ is a $\sigma'$ -group for a finite set of primes $\sigma=\sigma(f(x))$ depending only on $f(x)$ , then the Fitting height of $G$ is bounded in terms of the number irr $(f(x))$ of different irreducible factors in the decomposition of $f(x)$ . These bounds for the Fitting height are stronger than the well-known bounds in terms of the composition length $\alpha (|\varphi|)$ of $\langle\varphi\rangle$ when $\deg f(x)$ or irr $(f(x))$ is small in comparison with $\alpha (|\varphi|)$ .