DeldotB
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Homework Statement
Suppose that two neutrinos are created in the sun - call the states [itex]|{ \nu_1}\rangle[/itex] and [itex]|{ \nu_2}\rangle[/itex].
(Among many other things) I am asked to show that once the neutrinos have propigated a distance x after a time t, the states satisfy:
[itex]|{ \nu_1}(x,t)\rangle = e^{i \phi_1} | \nu_1(0,0) \rangle[/itex]
[itex]|{ \nu_2}(x,t)\rangle = e^{i \phi_2} | \nu_2(0,0) \rangle[/itex]
Where [itex]\phi_{1,2} = k_ix-E_it/ \hbar[/itex] where [itex]k_i= \sqrt{2m_iE/ \hbar^2}[/itex]
Homework Equations
Schrödinger Equation
The Attempt at a Solution
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This seems very simple, but I am missing a factor:
Solving the time independent Schrödinger equation yields: [itex]| \nu_1 (0,0) \rangle = e^{-ikx}[/itex] where [itex]k= \sqrt{2mE/ \hbar^2}[/itex].
Tagging on time dependence yields: [itex]| \nu_1 (t) \rangle = e^{-ikx} e^{-iEt/ \hbar}[/itex]= [itex]e^{-iEt/ \hbar} | \nu_1 (0,0) \rangle[/itex].
So my question is: I tagged on the time dependence factor (from solving the time dependent s.e) and I got [itex]e^{-iEt/ \hbar} | \nu_1 (0,0) \rangle[/itex]. But the problem states after the neutrinos have propigated a distance x after a time t. But isn't the "distance x" tied up in [itex]| \nu_1 (0,0) \rangle = e^{-ikx}[/itex] ?
Why are the solutions of the form [itex]|{ \nu_1}(x,t)\rangle = e^{i (k_ix-E_it/ \hbar)} | \nu_1(0,0) \rangle[/itex] instead of just [itex]|{ \nu_1}(x,t)\rangle = e^{iE_it/ \hbar} | \nu_1(0,0) \rangle[/itex]?
I hope this makes sense. Thanks in advance!