منابع مشابه
Finite groups have even more centralizers
For a finite group $G$, let $Cent(G)$ denote the set of centralizers of single elements of $G$. In this note we prove that if $|G|leq frac{3}{2}|Cent(G)|$ and $G$ is 2-nilpotent, then $Gcong S_3, D_{10}$ or $S_3times S_3$. This result gives a partial and positive answer to a conjecture raised by A. R. Ashrafi [On finite groups with a given number of centralizers, Algebra Collo...
متن کاملNatural bundles over smooth etendues
On the occasion of the 25th anniversary of the Halifax category years, where I had the privilege of participating, I would like to dedicate this talk to The Internationalists. The content of the talk is meant as a contribution to the program of investigating the differential geometry of smooth etendues by category theoretic (and groupoid theoretic) means. It represents reflections based on long...
متن کاملVector Bundles on Hirzebruch Surfaces Whose Twists by a Non-ample Line Bundle Have Natural Cohomology
Here we study vector bundles E on the Hirzebruch surface Fe such that their twists by a spanned, but not ample, line bundle M = OFe(h + ef) have natural cohomology, i.e. h(Fe, E(tM)) > 0 implies h(Fe, E(tM)) = 0.
متن کاملFinite Size Polyelectrolyte Bundles at Thermodynamic Equilibrium
We present the results of extensive computer simulations performed on solutions of monodisperse charged rod-like polyelectrolytes in the presence of trivalent counterions. To overcome energy barriers we used a combination of parallel tempering and hybrid Monte Carlo techniques. Our results show that for small values of the electrostatic interaction the solution mostly consists of dispersed sing...
متن کاملFinite Dimensional Subbundles of Loop Bundles
In this paper we consider vector bundles with fibre a loop space and structure group a loop group. We determine necessary and sufficient conditions for the structure group to reduce to the group of constant loops in terms of the existence of certain finite dimensional subbundles of the original vector bundle. Primary MSC Classification (2000): 58D15, 58B25
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
ژورنال
عنوان ژورنال: Topology
سال: 1977
ISSN: 0040-9383
DOI: 10.1016/0040-9383(77)90008-8