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Exemplu

Pentru (4.3.40) avem: $ M_1^{(E)}=M_1$, dar pentru $ n>1$, $ M_n^{(E)}\neq M_n$. Entropiile (4.4.48) si (4.4.49) devin:

$\displaystyle S^{(O)}=1-\sum\limits_{k\in \mathbb{Z}}\sum\limits_{m\in \mathbb{Z}}[\rho
_{k,k+2m}\cdot \rho _{k+2m,k}\cdot \exp (-2\frac{m^2}{\sigma ^2})+
$

$\displaystyle +(\frac{\Psi _{1/2}(\sigma )}{\Psi _0(\sigma )})^2\rho _{k,k+2m+1}\cdot \rho
_{k+2m+1,k}\cdot \exp (-2\frac{(m+\frac 12)^2}{\sigma ^2})]
$

$\displaystyle S^{(E)}=1-\sum\limits_{k\in \mathbb{Z}}\sum\limits_{m\in \mathbb{Z}}[\rho
_{k,k}\cdot \rho _{k+2m,k+2m}\cdot \exp (-2\frac{m^2}{\sigma ^2})+
$

$\displaystyle +(\frac{\Psi _{1/2}(\sigma )}{\Psi _0(\sigma )})^2\rho _{k,k}\cdot \rho
_{k+2m+1,k+2m+1}\cdot \exp (-2\frac{(m+\frac 12)^2}{\sigma ^2})]
$

Pentru o stare initiala de tip fuzzy:

$\displaystyle \widehat{\rho }=\widehat{\mathcal{F}}_d^{(\alpha )}\vert a\rangle...
...ehat{\mathcal{F}}_d^{(\alpha )+}\quad a\in \mathbb{Z},\alpha \in \mathbb{R}_{+}$ (4.4.50)

(4.4.48) si (4.4.49) sunt egale:

$\displaystyle S^{(O)}=S^{(E)}=1-\sum\limits_{n,k\in \mathbb{Z}}(\sum\limits_{m\...
...ga _{mn}^{(\sigma )}}})^2{
\omega _{n,a}^{(\alpha )}\omega _{k,a}^{(\alpha )}}
$

care pentru (4.3.40) este:
    $\displaystyle 1-\frac 1{\left( \Psi _0(\alpha )\right) ^2}[\Psi _0(\frac \alpha 2)\Psi
_0(\frac{\alpha \cdot \sigma }{\sqrt{2\cdot (\alpha ^2+2\sigma ^2)}})+$  
    $\displaystyle +(\frac{\Psi _{1/2}(\sigma )}{\Psi _0(\sigma )})^2\Psi _{1/2}(\fr...
...Psi _{1/2}(\frac{\alpha \cdot \sigma }{\sqrt{2\cdot (\alpha ^2+2\sigma ^2)
}})]$  

Utilizand aproximatiile de la (4.3.41), pentru o pozitie initiala exacta $ (\alpha <0.2)$, rezultatul este independent de parametrul de fuzzificare $ \sigma $, $ S=0$ (starea ramane aproape pura), in timp ce pentru $ \alpha >1.6$ (pozitie initiala fuzzy), rezultatul este $ 1-\frac \alpha {
\sqrt{\pi }}$ pentru masuratori exacte $ (\sigma <0.2)$ si $ 1-\frac \sigma {
\sqrt{2\cdot (\alpha ^2+2\sigma ^2)}}$ pentru masuratori non-exacte (daca $ \alpha \ll \sigma $ aceasta atinge valoarea maxima pentru (4.4.47), $ S=\frac 12$)



root 2002-11-18