- #1
LizardWizard
- 18
- 0
Homework Statement
We are given the Hamiltonian H and an observable A
##H=\begin{pmatrix}
2 & 0 & 0\\0 & 0 & 1\\0 & 1 & 0
\end{pmatrix}\hbar\omega
A=
\begin{pmatrix}
1 & 0 & 0\\0 & 1 & 0\\0 & 0 & -1
\end{pmatrix}a
##
We are also told that at ##t=0## we have that a measurement of A gives us -a, and then we are asked to determine the generic state of the system at time t
The attempt at a solution
For starters, the solution the professor gives is $$|\psi(t)\rangle=
\begin{pmatrix}
0\\-isin(\omega t)\\cos(\omega t)
\end{pmatrix}
$$
Now while I don't know how to arrive to this solution in particular, I know this result most likely follows from $$\psi(t)=e^{-iEt/\hbar}$$
since we already have that ##E=\hbar\omega##
But how exactly do I arrive at the solution provided? This is somewhat different from all the exercises I've seen so far so I don't really know the calculations involved.
We are given the Hamiltonian H and an observable A
##H=\begin{pmatrix}
2 & 0 & 0\\0 & 0 & 1\\0 & 1 & 0
\end{pmatrix}\hbar\omega
A=
\begin{pmatrix}
1 & 0 & 0\\0 & 1 & 0\\0 & 0 & -1
\end{pmatrix}a
##
We are also told that at ##t=0## we have that a measurement of A gives us -a, and then we are asked to determine the generic state of the system at time t
The attempt at a solution
For starters, the solution the professor gives is $$|\psi(t)\rangle=
\begin{pmatrix}
0\\-isin(\omega t)\\cos(\omega t)
\end{pmatrix}
$$
Now while I don't know how to arrive to this solution in particular, I know this result most likely follows from $$\psi(t)=e^{-iEt/\hbar}$$
since we already have that ##E=\hbar\omega##
But how exactly do I arrive at the solution provided? This is somewhat different from all the exercises I've seen so far so I don't really know the calculations involved.