Results 11 to 20 of about 5,659,086 (164)
Groups with minimax commutator subgroup [PDF]
International Journal of Group Theory, 2014 A result of Dixon, Evans and Smith shows that if $G$ is a locally (soluble-by-finite) group whose proper subgroups are (finite rank)-by-abelian, then $G$ itself has this property, i.e. the commutator subgroup of~$G$ has finite rank.
Francesco de Giovanni, Trombetti
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On groups with many normal subgroups [PDF]
International Journal of Group Theory, 2023 The structure of groups which are rich in normal subgroups has been investigated by several authors. Here, we prove that if a radical group G has normal deviation, which means that the set of its non-normal subgroups satisfies a very weak chain condition,
Alessio Russo, Mario Viscusi
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Groups whose Proper Subgroups of Infinite Rank are Minimax-by-Nilpotent or Nilpotent-by-Minimax [PDF]
Advances in Group Theory and Applications, 2020 Let M denote the class of of soluble-by-finite minimax groups, and N the class of nilpotent groups. The main result states that if G is a group of infinite rank whose proper subgroups of infinite rank are MN-groups, then G is either in MN or it is a ...
Amel Zitouni
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Robust optimization of catheter positions and dwell times for HDR prostate brachytherapy. [PDF]
Med PhysAbstract Background HDR prostate brachytherapy plans are sensitive to catheter placement uncertainty, as discrepancies between planned and delivered catheter positions can degrade target coverage and increase organ at risk dose. Current inverse planning methods optimize dwell times for a fixed implant geometry and do not account for geometric ...
Schulz JB +3 more
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On some commutative invariants of modules over minimax nilpotent groups
Доповiдi Нацiональної академiї наук України, 2022 In the paper we introduce a finite system of invariants for modules over minimax nilpotent groups which consists of classes of equivalent prime ideals of the group algebra of an Abelian minimax group. In particuly, introduced system of invariants allows
A.V. Tushev
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On invariant ideals in group rings of torsion-free minimax nilpotent groups
Researches in Mathematics, 2023 Let $k$ be a field and let $N$ be a nilpotent minimax torsion-free group acted by a solvable group of operators $G$ of finite rank. In the presented paper we study properties of some types of $G$-invariant ideals of the group ring $kN$.
A.V. Tushev
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Groups with Finitely Many Isomorphism Classes of Non-Normal Subgroups [PDF]
Advances in Group Theory and Applications, 2020 We study groups in which the non-normal subgroups fall into finitely many isomorphism classes. We prove that a locally generalized radical group with this property is abelian-by-finite and minimax.
Leonid A. Kurdachenko +2 more
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On the structure of groups admitting faithful modules with certain conditions of primitivity
Researches in Mathematics, 2023 In the paper we study structure of soluble-by-finite groups of finite torsion-free rank which admit faithful modules with conditions of primitivity. In particular, we prove that under some additional conditions if an infinite finitely generated linear ...
A.V. Tushev
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Groups with soluble minimax conjugate classes of subgroups [PDF]
Iranian Journal of Numerical Analysis and Optimization, 2008 A classical result of Neumann characterizes the groups in which each subgroup has finitely many conjugates only as central-by-finite groups. If X is a class of groups, a group G is said to have X-conjugate classes of subgroups if G/coreG(NG(H)) 2 X for ...
Francesco Russo
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Existence of solutions to steady Navier-Stokes equations via a minimax approach
Electronic Journal of Differential Equations, 2023 Our objective in this paper is to develop and utilize a minimax principle for proving the existence of symmetric solutions for the stationary Navier-Stokes equations.
Amin Fereidooni +2 more
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