C stability and Ω - stability conjectures for flows
نویسندگان
چکیده
There is a gap in the proof of Lemma VII.4 in [1]. We present an alternative proof of Theorem B (C 1 Ω-stable vector fields satisfy Axiom A) in [1]. The novel and essential part in the proof of the stability and Ω-stability conjectures for flows is the connecting lemma introduced in [1]. A mistake in the proof of the last conjecture was pointed out to me by Toyoshiba [5], who later also provided an independent proof of it, again based on the connecting lemma and previous arguments by Mañé and Palis. The crucial step to the proof of Theorem B is the separation of singu-larities from periodic orbits ([1, Corollary III]) by the C 1 connecting lemma ([1, Theorem A]). After the separation, the proof proceeds based on Mañé's theorems used in [3] and we still rely on Palis's argument in [4], proving first the density of Axiom A diffeomorphisms in the set of C 1 Ω-stable ones to then show that every C 1 Ω-stable diffeomorphism satisfies Axiom A. Let G 1 Ω (M) be the set of C 1 Ω-stable vector fields on a compact smooth boundaryless manifold M with the C 1 topology and X ∈ G 1 Ω (M). As in [1], we prove the hyperbolicity of Per(X) (= Ω(X) − Sing(X)) by induction. In fact, we prove that P j (X) is hyperbolic assuming that j−1 i=0 P i (X) is hyperbolic for some 1 ≤ j ≤ dimM − 1, where P i (X) is the closure of the set of periodic points with index i (dimension of the stable subspace), which is enough to conclude that X satisfies Axiom A. For a dense subset of G 1 Ω (M), we can use the statement of [1, Lemma VII.4] by an already classic argument on set-valued functions of C 1 vector fields. In fact, there is a residual subset of the set of C 1 vector fields (therefore of G 1 Ω (M)) in which the closure of the set of hyperbolic periodic points of saddle type moves continuously with respect to vector fields (see for instance the proof of [1, Corollary II] for this kind of argument). Therefore, as proved in [1], we get the density of Axiom A vector fields in G 1 Ω (M). Then, by Ω-conjugacy, we see that Ω(X) can be decomposed into a finite union of disjoint …
منابع مشابه
Foreign Trade and International Financial Flows: Implications for Economic Stability in the Selected ECOWAS Countries
T his study investigates the effects of extra-ECOWAS merchandise trade and investment flows on the transmission of business cycles in the selected ECOWAS between 1985 and 2014. The study finds that total trade and foreign direct investment (FDI) significantly influence the transmission of business cycles with elasticities of 1.1 and 0.7, respectively in the long run. There are little vari...
متن کاملThe effect of boundary conditions on the accuracy and stability of the numerical solution of fluid flows by Lattice-Boltzmann method
The aim of this study is to investigate the effect of boundary conditions on the accuracy and stability of the numerical solution of fluid flows in the context of single relaxation time Lattice Boltzmann method (SRT-LBM). The fluid flows are simulated using regularized, no-slip, Zou-He and bounce back boundary conditions for straight surfaces in a lid driven cavity and the two-dimensional flow ...
متن کاملBirational Stability of the Cotangent Bundle
We introduce a birational invariant κ++(X |∆) ≥ κ(X |∆) for orbifold pairs (X |∆) by considering the ∆-saturated Kodaira dimensions of rank-one coherent subsheaves of Ω X . The difference between these two invariants measures the birational unstability of Ω(X |∆). Assuming conjectures of the LMMP, we obtain a simple geometric description of the invariant κ++(X |∆), as the Kodaira dimension of t...
متن کاملDynamics of higher order rational difference equation $x_{n+1}=(alpha+beta x_{n})/(A + Bx_{n}+ Cx_{n-k})$
The main goal of this paper is to investigate the periodic character, invariant intervals, oscillation and global stability and other new results of all positive solutions of the equation$$x_{n+1}=frac{alpha+beta x_{n}}{A + Bx_{n}+ Cx_{n-k}},~~ n=0,1,2,ldots,$$where the parameters $alpha$, $beta$, $A$, $B$ and $C$ are positive, and the initial conditions $x_{-k},x_{-k+1},ldots,x_{-1},x_{0}$ are...
متن کاملEvaluation of Roe s Method with Different Limiters in Supersonic 2-D and Axisymmetric Flows
2-D and axisymmetric Navier-Stokes equations are solved using Reiman-Roe solver with different limiters for second-order accurate schemes. The results were obtained for supersonic viscous flows over semi-infinite axisymmetric and 2-D bodies. The free stream Mach numbers were 7.78 and 16.34. The stability of Roe method with different limiters and entropy conditions were considered. The results s...
متن کامل