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Pentru operatorul pozitie $ \widehat{x}=\int\limits_{\Bbb{R}}x\cdot \widehat{E
}_{(x)}(dx)$ se pot obtine rezultate similare celor de mai sus$ .$ Pentru operatorul canonic conjugat: $ \widehat{k}=\int\limits_{\Bbb{R}}k\cdot
\widehat{E}_{(k)}(dk)$ obtinem:

$\displaystyle M_1^{(O)}(\widehat{E}_{(k)})=Tr(\widehat{\rho }_{post}^{(c)}\int\limits_{
\Bbb{R}}k\cdot \widehat{E}_{(k)}(dk))=
$


  $\displaystyle =$ $\displaystyle Tr(\int\limits_{\Bbb{R}}dx\widehat{\mathcal{A}}_x\widehat{\rho }\widehat{
\mathcal{A}}_x^{+}\int\limits_{\Bbb{R}}k\cdot \widehat{E}_{(k)}(dk))=$ (4.4.51)
  $\displaystyle =$ $\displaystyle i\int\limits_{\Bbb{R}}dy[(\frac{\partial \rho }{\partial y^{\prim...
...mits_{\Bbb{R}}dx(\frac{
\partial f}{\partial x^{\prime }})_{(x^{\prime }=x-y)}]$  


$\displaystyle M_1^{(E)}(\widehat{E}_{(k)})$ $\displaystyle =$ $\displaystyle Tr(\widehat{\rho }_{post}^{(E,c)}\int
\limits_{\Bbb{R}}k\cdot \widehat{E}_{(k)}(dk))=$  
  $\displaystyle =$ $\displaystyle Tr(\int\limits_{\Bbb{R}}dx\widehat{\mathcal{A}}_x^{(E)}\widehat{\...
...idehat{\mathcal{A}}_x^{(E)}\int\limits_{\Bbb{R}}k\cdot \widehat{E}
_{(k)}(dk))=$ (4.4.52)
  $\displaystyle =$ $\displaystyle -\frac i2\int\limits_{\Bbb{R}}dy\cdot \rho (y,y)\int\limits_{\Bbb{R}}dx(
\frac{\partial f}{\partial x^{\prime }})_{(x^{\prime }=x-y)}$  

Diferenta dintre (4.4.51) si (4.4.52) este data de termenul $ i\int\limits_{\Bbb{R}}(\frac{\partial \rho }{\partial y^{\prime }}
)_{(y,y^{\prime }=y)}dy$, care este un termen de memorie pentru coerenta cuantica a starii initiale (inainte de masuratoarea fuzzy a pozitiei), care, totusi, nu depinde de parametrii de fuzzificare.



root 2002-11-18