Results 21 to 30 of about 498 (210)
mSphere, 2021 Shannon’s entropy is a popular alpha diversity metric because it estimates both richness and evenness in a single equation. However, since its value is dependent on both those parameters, there is theoretically an infinite number of richness/evenness ...
Jeff Gauthier, Nicolas Derome
doaj +1 more source
Infinite symmetric ergodic index and related examples in infinite measure [PDF]
Studia Mathematica, 2018 We define an infinite measure-preserving transformation to have infinite symmetric ergodic index if all finite Cartesian products of the transformation and its inverse are ergodic, and show that infinite symmetric ergodic index does not imply that all products of powers are conservative, so does not imply power weak mixing.
Loh, Isaac +2 more
openaire +2 more sources
Nonplanarity of Iterated Line Graphs
Journal of Mathematics, 2020 The 1-crossing index of a graph G is the smallest integer k such that the kth iterated line graph of G has crossing number greater than 1. In this paper, we show that the 1-crossing index of a graph is either infinite or it is at most 5.
Jing Wang
doaj +1 more source
Infinite index subalgebras of depth two [PDF]
Proceedings of the American Mathematical Society, 2008 An algebra extension A | B
openaire +2 more sources
The Canonical Endomorphism for Infinite Index Inclusions
Zeitschrift für Analysis und ihre Anwendungen, 1999 We give purely algebraic characterisations of the canonical endomorphism in in-teresting infinite index cases, continuing previous works of Longo and the authors. We apply these results when compact and discrete (but not necessarily finite-dimensional) Woronowicz algebras act alternately on the factors in the various levels of Jones’ tower.
Fidaleo Francesco, Isola Tommaso
openaire +4 more sources
A degree theory for a class of perturbed Fredholm maps
Fixed Point Theory and Applications, 2005 We define a notion of degree for a class of perturbations of nonlinear Fredholm maps of index zero between infinite-dimensional real Banach spaces. Our notion extends the degree introduced by Nussbaum for locally α-contractive perturbations of the ...
Massimo Furi +2 more
doaj +2 more sources
The Index Problem for Infinite Symmetric Groups [PDF]
Proceedings of the American Mathematical Society, 1964 Let M be an infinite set with cardinal X, S(X, Y) = o-: ois a permutation on M such that I spt oj I d has no subgroups of index less than or equal Z. In this paper, the following generalization of these results is proven.
openaire +1 more source
On Groups with Extreme Centralizers and Normalizers [PDF]
Advances in Group Theory and Applications, 2016 An FCI-group is a group in which every non-normal cyclic subgroup has finite index in its centralizer and an FNI-group is one in which every non-normal subgroup has finite index in its normalizer.
Derek J.S. Robinson
doaj +1 more source
The classification of symmetry protected topological phases of one-dimensional fermion systems
Forum of Mathematics, Sigma, 2021 We introduce an index for symmetry-protected topological (SPT) phases of infinite fermionic chains with an on-site symmetry given by a finite group G. This index takes values in $\mathbb {Z}_2 \times H^1(G,\mathbb {Z}_2) \times H^2(G, U(1)_{\mathfrak {p}
Chris Bourne, Yoshiko Ogata
doaj +1 more source
A Planar Calculus for Infinite Index Subfactors [PDF]
Communications in Mathematical Physics, 2012 We develop an analog of Jones' planar calculus for II_1-factor bimodules with arbitrary left and right von Neumann dimension. We generalize to bimodules Burns' results on rotations and extremality for infinite index subfactors. These results are obtained without Jones' basic construction and the resulting Jones projections.
openaire +2 more sources