The proximal relation and the group P

Author(s):  
David B. Ellis ◽  
Robert Ellis
Keyword(s):  
2018 ◽  
Vol 40 (6) ◽  
pp. 1715-1728
Author(s):  
TAO YU ◽  
XIAOMIN ZHOU

Let $\unicode[STIX]{x1D70B}:(X,T)\rightarrow (Y,S)$ be an extension between minimal systems; we consider its relative sensitivity. We obtain that $\unicode[STIX]{x1D70B}$ is relatively $n$-sensitive if and only if the relative $n$-regionally proximal relation contains a point whose coordinates are distinct; and the structure of $\unicode[STIX]{x1D70B}$ which is relatively $n$-sensitive but not relatively $(n+1)$-sensitive is determined. Let ${\mathcal{F}}_{t}$ be the families consisting of thick sets. We introduce notions of relative block ${\mathcal{F}}_{t}$-sensitivity and relatively strong ${\mathcal{F}}_{t}$-sensitivity. Let $\unicode[STIX]{x1D70B}:(X,T)\rightarrow (Y,S)$ be an extension between minimal systems. Then the following Auslander–Yorke type dichotomy theorems are obtained: (1) $\unicode[STIX]{x1D70B}$ is either relatively block ${\mathcal{F}}_{t}$-sensitive or $\unicode[STIX]{x1D719}:(X,T)\rightarrow (X_{\text{eq}}^{\unicode[STIX]{x1D70B}},T_{\text{eq}})$ is a proximal extension where $(X_{\text{eq}}^{\unicode[STIX]{x1D70B}},T_{\text{eq}})\rightarrow (Y,S)$ is the maximal equicontinuous factor of $\unicode[STIX]{x1D70B}$. (2) $\unicode[STIX]{x1D70B}$ is either relatively strongly ${\mathcal{F}}_{t}$-sensitive or $\unicode[STIX]{x1D719}:(X,T)\rightarrow (X_{d}^{\unicode[STIX]{x1D70B}},T_{d})$ is a proximal extension where $(X_{d}^{\unicode[STIX]{x1D70B}},T_{d})\rightarrow (Y,S)$ is the maximal distal factor of $\unicode[STIX]{x1D70B}$.


2010 ◽  
Vol 20 (09) ◽  
pp. 2925-2935 ◽  
Author(s):  
FRANCISCO BALIBREA ◽  
JUAN L. G. GUIRAO ◽  
PIOTR OPROCHA

This article is devoted to the study of invariant ε-scrambled sets. We show that every topologically mixing map with at least one fixed point contains at least one such set. Additionally we show that this condition can be weakened in the case of symbolic dynamics, e.g. mixing can be replaced by transitivity. Some relations between mixing and proximal relation are also studied.


2020 ◽  
Vol 63 (9) ◽  
pp. 1757-1776 ◽  
Author(s):  
Eli Glasner ◽  
Wen Huang ◽  
Song Shao ◽  
Xiangdong Ye

2000 ◽  
Vol 20 (3) ◽  
pp. 641-662 ◽  
Author(s):  
F BLANCHARD ◽  
B HOST ◽  
A MAASS

In a topological dynamical system $(X,T)$ the complexity function of a cover ${\cal C}$ is the minimal cardinality of a sub-cover of $\bigvee_{i=0}^n T^{-i}{\cal C}$. It is shown that equicontinuous transformations are exactly those such that any open cover has bounded complexity. Call scattering a system such that any finite cover by non-dense open sets has unbounded complexity, and call 2-scattering a system such that any such 2-set cover has unbounded complexity: then all weakly mixing systems are scattering and all 2-scattering systems are totally transitive. Conversely, any system that is not 2-scattering has covers with complexity at most $n+1$. Scattering systems are characterized topologically as those such that their cartesian product with any minimal system is transitive; they are consequently disjoint from all minimal distal systems. Finally, defining $(x,y)$, $x\ne y$, to be a complexity pair if any cover by two non-trivial closed sets separating $x$ from $y$ has unbounded complexity, we prove that 2-scattering systems are disjoint from minimal isometries; that in the invertible case the complexity relation is contained in the regionally proximal relation and, when further assuming minimality, coincides with it up to the diagonal.


2019 ◽  
Vol 8 (2) ◽  
Author(s):  
Joseph Alo Nwafor ◽  
Obinna Onwe Uchewa ◽  
Amaobi Jude Egwu ◽  
Godwin Ikechukwu Nwajagu

There was no direct relationship between its formation and the axillary artery. Hence, it may be not be readily compromised. The site of MN formation was in proximal relation to the insertion of the coracobrahialis. This is clinically important as it may give a reinforced innervation to the muscle and proprioceptive impulses to medial fibres of the brachialis muscle. Conversely, the MN may be compressed by the tendon of the coracobrahialis, affecting its sympathetic filaments to the brachial artery. Furthermore, when present, it may be severed during reconstructive surgeries around the mid arm as the medial intermuscular septum fades out above the insertion of the coracobrachialis muscle. This report highlights the presence of a significant anatomical variation of the median nerve with regards to its site of formation, roots morphology and distribution, as well as its arterial relations for proper planning of surgeries.Key Words: Median nerve, arterial relations, right upper extremity, Morphology.


1995 ◽  
Vol 347 (6) ◽  
pp. 2139-2146 ◽  
Author(s):  
Joseph Auslander ◽  
David B. Ellis ◽  
Robert Ellis
Keyword(s):  

Sign in / Sign up

Export Citation Format

Share Document