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facenian
Sep19-09, 08:44 PM
1. The problem statement, all variables and given/known data
Let \psi(x,y,z)=\psi(\vec{r}) be the normalized wave function of a particle.Express in terms of \psi(\vec{r}) the probability for a simultaneous measurements o X y P_z to yield :
x_1 \leq x \leq x_2
p_z \geq 0



2. Relevant equations
<\vec{p}|\vec{r}>=\frac{1}{(2\pi\hbar)^{3/2}}e^{-i\vec{p}.\vec{r}/\hbar}
<\vec{p}|\psi>=\frac{1}{(2\pi\hbar)^{3/2}}\int \psi(\vec{r}) e^{-i\vec{p}.\vec{r}/\hbar} dr^3


3. The attempt at a solution
I have reached the following result:
\int_{-\infty}^{\infty}dz\int_{-\infty}^{\infty}dy\int_{x_1}^{x_2}dx \int_{-\infty}^{\infty}dp_x\int_{-\infty}^{\infty}dp_y\int_0^{\infty}dp_z <\vec{p}|\vec{r}>\psi(\vec{r})<\psi|\vec{p}>
I need to know two things: 1) is my result correct? 2) in case it is correct, is there any other more simple or concrete answer?

elduderino
Sep20-09, 05:44 AM
Sorry, I am not answering your question. But could you explain how you arrived at the expression <\vec{p}|\vec{r}>\psi(\vec{r})<\psi|\vec{p}>

facenian
Sep20-09, 08:00 AM
Sorry, I am not answering your question. But could you explain how you arrived at the expression <\vec{p}|\vec{r}>\psi(\vec{r})<\psi|\vec{p}>


I evalueted de expression <\psi|P_2P_1|\psi> where P_1 and P_2 are the proyectors:
P_1=\int_{-\infty}^{\infty}dz\int_{-\infty}^{\infty}dy\int_{x_1}^{x_2}dx|x,y,z><x,y,z|
P_2=\int_{-\infty}^{\infty}dp_x\int_{-\infty}^{\infty}dp_y\int_0^{\infty}dp_z|p_x,p_y,p_ z><p_x,p_y,p_z|
But I'm sure whether what I'm doing is correct