From: guyeux Date: Fri, 1 Jun 2012 12:33:47 +0000 (+0200) Subject: Pouet X-Git-Url: https://bilbo.iut-bm.univ-fcomte.fr/and/gitweb/review_prng.git/commitdiff_plain/88947af28fe7e7f5b1dd35d21d71b2f69130b798?ds=sidebyside Pouet --- diff --git a/mabase.bib b/mabase.bib index 0033443..d5e366c 100644 --- a/mabase.bib +++ b/mabase.bib @@ -14,6 +14,25 @@ timestamp = {2009.06.29} } + +@INCOLLECTION{gb11:bc, + author = {Guyeux, Christophe and Bahi, Jacques}, + title = {A Topological Study of Chaotic Iterations. Application to Hash Functions}, + booktitle = {CIPS, Computational Intelligence for Privacy and Security}, + publisher = {Springer}, + year = {2012}, + volume = {394}, + series = {Studies in Computational Intelligence}, + pages = {51--73}, + note = {Revised and extended journal version of an IJCNN best paper}, + classement = {OS}, + doi = {10.1007/978-3-642-25237-2_5}, + domainehal = {INFO:INFO_DC, INFO:INFO_CR, INFO:INFO_MO}, + equipe = {and}, + inhal = {no}, + url = {http://dx.doi.org/10.1007/978-3-642-25237-2_5} +} + @INPROCEEDINGS{BattiatoCGG99, author = {Sebastiano Battiato and Dario Catalano and Giovanni Gallo and Rosario Gennaro}, diff --git a/review_prng.tex b/review_prng.tex index aa5ebf2..0cdeb04 100644 --- a/review_prng.tex +++ b/review_prng.tex @@ -232,43 +232,36 @@ With all this material, the study of chaotic iterations as a discrete dynamical system has then be realized. This study is summarized in the next section. -% \frame{ -% \frametitle{\'Etude de $(\mathcal{X},d)$} -% \begin{block}{Propriétés de $(\mathcal{X},d)$} -% \begin{itemize} -% \item $\mathcal{X}$ est infini indénombrable -% \vspace{0.15cm} -% \item $(\mathcal{X},d)$ est un espace métrique compact, complet et parfait -% \end{itemize} -% \end{block} -% -% \vspace{0.5cm} -% -% \begin{block}{\'Etude de $G_{f_0}$} -% $G_{f_0}$ est surjective, mais pas injective \vspace{0.3cm}\newline $\Rightarrow (\mathcal{X},G_{f_0})$ pas réversible. -% \end{block} - -% } +\subsection{Topological Properties of Chaotic Iterations} +The topological space on which chaotic iterations are defined has +firstly been investigated, leading to the following result~\cite{gb11:bc,GuyeuxThese10}: +\begin{proposition} +$\mathcal{X}$ is an infinitely countable metric space, being both +compact, complete, and perfect (each point is an accumulation point). +\end{proposition} +These properties are required in some topological specific +formalization of a chaotic dynamical system, justifying their +proofs. +Concerning $G_{f_0}$, it has been stated that~\cite{GuyeuxThese10}. +\begin{proposition} +$G_{f_0}$ is surjective, but not injective, and so the dynamical system $(\mathcal{X},G_{f_0})$ is not reversible. -%%\frame{ -%% \frametitle{Etude des périodes} -%% \begin{block}{Multiplicité des périodes ?} -%% Soit $f_0:\mathds{B}^\mathsf{N} \rightarrow \mathds{B}^\mathsf{N}$ la négation vectorielle. -%% \begin{itemize} -%% \item $\forall k \in \mathds{N}, Per_{2k+1}(G_{f_0}) = \varnothing, card\left(Per_{2k+2}(G_{f_0})\right)>0$ \vspace{0.3cm} \linebreak $\Rightarrow G_{f_0}$ pas chaotique sur $\mathcal{X}$ -%% \item Cependant : -%% \begin{itemize} -%% \item Il y a chaos sur $\mathcal{X}^G = \mathcal{P}\left(\llbracket 1,\mathsf{N}\rrbracket\right)^\mathds{N}\times \mathds{B}^\mathsf{N}$. -%% \item $G_{f_0}$ possède plus de $n^2$ points périodiques de période $2n$. -%% \end{itemize} -%% \end{itemize} -%% \end{block} -%% \uncover<2->{ -%% Cette multiplicité des périodes n'est pas le désordre complet... -%% } -%%} +Furthermore, if we denote by $Per_k(f)$ the set of periodic points +of period $k$ for $f$, we have + $\forall k \in \mathds{N}, Per_{2k+1}(G_{f_0}) = \varnothing, card\left(Per_{2k+2}(G_{f_0})\right)>0$. +\end{proposition} + +So $\Rightarrow G_{f_0}$ does not present the existence of points of any period referred as chaos in the article of Li and Yorke~\cite{Li75}. +However~\cite{GuyeuxThese10}: + \begin{itemize} + \item This kind of disorder can be stated on $\mathcal{X}^G = \mathcal{P}\left(\llbracket 1,\mathsf{N}\rrbracket\right)^\mathds{N}\times \mathds{B}^\mathsf{N}$. + \item $G_{f_0}$ possesses more than $n^2$ points of period $2n$. + \end{itemize} +Additionally, this existence of points of any period has been rejected +by the community to the benefit of more recent notions of chaos, as +they are detailed in the following paragraphs.