Related papers: Inducing periodicity and chaos by negative feedbac…

The paper has been withdrawn by the author due to a gap in Proof of Theorem 1.1.

This paper has been withdrawn by the authors due to a likely hole in the proof.

This paper has been withdrawn by the author(s) in the light of several other works available and due to a misunderstanding in the authorships.

We withdraw this paper due to insufficient arguments in the derivation of Theorem 1. See quant-ph/0005062 for the new paper

This paper has been withdrawn by the author. The statement of the Main Theorem but is wrong in general, there have been provided counterexamples. The main theorem only holds conditionally, under the finiteness statement of theorem 2.8.

This paper has been withdrawn by the authors due to missing references to earlier work and an error in the interpretation of Figures 2 and 3. A corrected version is in preparation.

This paper has been withdrawn by the author due to a crucial error in equation.

This paper has been withdrawn by the author because there is a gap in Lemma 9.

This paper is wrong and is therefore withdrawn.

This paper has been withdrawn by the author due to a crucial error in one of equation in (3).

This paper has been withdrawn by the author. Much simpler proof of the main result was obtained which led to major changes in the presentation.

This paper had been withdrawed

This paper has been withdrawn by the author due to a crucial sign error.

This paper has been withdrawn by the authors

This paper has been withdrawn by the author due to new results to be added.

This paper has been withdrawn by the author due to an error in the computation of the central charge.

This paper has been withdrawn by the author due to rewritting and skipping crucial sign errors.

This paper has been withdrawn by the author: it was a too preliminary version.

This paper has been withdrawn by the authors due to the crucial wrong assumption following Eq. 9.

The paper has benn withdrawn because the computation of the external virial contains an error which invalidate the main result.