Results 91 to 100 of about 73,865 (284)
Compact Manifolds With Unbounded Nilpotent Fundamental Groups and Positive Ricci Curvature
Communications on Pure and Applied Mathematics, EarlyView.ABSTRACT It follows from the work of Kapovitch and Wilking that a closed manifold with nonnegative Ricci curvature has a uniformly almost nilpotent fundamental group. Leftover questions and conjectures, have asked if in this context the fundamental group is actually uniformly almost abelian. The main goal of this work is to construct examples (Mk9,gk)$(
Elia Bruè, Aaron Naber, Daniele Semola
wiley +1 more source
Hilbert's Basis Theorem for Poisson Ore Extensions
Mathematische Nachrichten, EarlyView.ABSTRACT We prove an analogue of Hilbert's basis theorem for Poisson Ore extensions and Poisson Laurent Ore extensions. We also obtain corresponding results for iterated Poisson Ore extensions and iterated Poisson Laurent Ore extensions associated to commuting Poisson‐pairs.
Per Bäck +3 more
wiley +1 more source
International Journal of Mathematics and Mathematical Sciences, 1996 Let R be a ring, and let N and C denote the set of nilpotents and the center of R, respectively. R is called generalized periodic if for every x∈R\(N⋃C), there exist distinct positive integers m, n of opposite parity such that xn−xm∈N⋂C.
Howard E. Bell, Adil Yaqub
doaj +1 more source
Non-commutativity and non-associativity of the doubled string in non-geometric backgrounds [PDF]
Journal of High Energy Physics, 2014 We use a T-duality invariant action to investigate the behaviour of a string in non-geometric backgrounds, where there is a non-trivial global O(D, D) patching or monodromy.
Chris D. A. Blair
semanticscholar +1 more source
A Quasi-Commutative Ring That is Not Neo-Commutative [PDF]
Proceedings of the American Mathematical Society, 1994 An example of a ring that is quasi-commutative but not neo-commutative is given.
openaire +1 more source
Grothendieck and ℓ∞$\ell _\infty$‐Grothendieck Subspaces of ℓ∞$\ell _\infty$
Mathematische Nachrichten, EarlyView.ABSTRACT Let c=2ℵ0$\mathfrak {c}=2^{\aleph _0}$. We prove that ℓ∞$\ell _\infty$ contains 2c$2^{\mathfrak {c}}$ pairwise non‐isomorphic non‐reflexive Grothendieck subspaces. They may all be chosen to contain the canonical copy of c0$c_0$ and to have an infinite‐dimensional reflexive quotient. This is optimal and answers Problem 24 of González and Kania [
Manuel González, Tomasz Kania
wiley +1 more source
Some metric characterizations of commutativity in C*-algebras [PDF]
Surveys in Mathematics and its ApplicationsWe study Le Page's theorem in the context of C*-algebras and obtain several characterizations of commutativity and centrality implied by identities or inequalities satisfied by the norm.
Florin Pop
doaj
On commutativity of rings with generalized derivations
, 2016 Let R be a prime ring, extended centroid C, Utumi quotient ring U, and m, n ≥ 1 are fixed positive integers, F a generalized derivation associated with a nonzero derivation d of R. We study the case when one of the following holds: (i) F ( x ) ∘ m d ( y )
N. Rehman, M. Raza, Tarannum Bano
semanticscholar +1 more source
Non-commutativity and Local Indistinguishability of Quantum States [PDF]
Scientific Reports, 2014 We study the local indistinguishability problem of quantum states. By introducing an easily calculated quantity, non-commutativity, we present an criterion which is both necessary and sufficient for the local indistinguishability of a complete set of ...
Teng Ma +3 more
semanticscholar +1 more source
Graded Differential Polynomial Rings
Mathematische Nachrichten, EarlyView.ABSTRACT We study differential polynomial rings R[t;δ]$R[t;\delta]$ over Γ$\Gamma$‐graded rings, where Γ$\Gamma$ is an arbitrary group. We show that R[t;δ]$R[t;\delta]$ admits a Γ$\Gamma$‐grading compatible with that of R$R$ if and only if δ$\delta$ is a γ$\gamma$‐derivation for some γ∈CΓ(ΓR)$\gamma \in C_\Gamma (\Gamma _R)$, and that this grading is ...
Yassine Ait Mohamed
wiley +1 more source