Conjugate-permutable subgroup

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In mathematics, in the field of group theory, a conjugate-permutable subgroup is a subgroup that commutes with all its conjugate subgroups. The term was introduced by Tuval Foguel in 1997 [1] and arose in the context of the proof that for finite groups, every quasinormal subgroup is a subnormal subgroup.

Clearly, every quasinormal subgroup is conjugate-permutable.

In fact, it is true that for a finite group:

Conversely, every 2-subnormal subgroup (that is, a subgroup that is a normal subgroup of a normal subgroup) is conjugate-permutable.

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Tuval Shmuel Foguel is Professor of Mathematics at Adelphi University in Garden City, New York. Tuval Foguel was born in 1959 in Berkeley, California to Hava and Shaul Foguel and he is a descendant of Saul Wahl. Through his mother Hava, Professor Foguel is related to Nahum Sokolow. Professor Foguel received his B.S. in mathematics from York College, City University of New York in 1988 and his PhD in Mathematics under Michio Suzuki from the University of Illinois at Urbana–Champaign in 1992 with a focus on finite groups. He has introduced the term conjugate-permutable subgroup. In the past, Professor Foguel has also taught at the University of the West Indies, North Dakota State University, Auburn University Montgomery, and Western Carolina University.

References

  1. Foguel, Tuval (1997), "Conjugate-permutable subgroups", Journal of Algebra, 191 (1): 235–239, doi:10.1006/jabr.1996.6924, MR   1444498 .