I have a few questions about the time dependence of energy and probability etc. of systems.(adsbygoogle = window.adsbygoogle || []).push({});

Firstly...

Say I have a particle in an infinite 1-D well.

I can work out the general wave function as a Fourier sum of the orthogonal sine functions.

Hence, the average/expectation value of the energy is :

< H > = SUM (C_n)^2 (E_n) where C_n are the Fourier coefficients and E_n is the energy of the particle in the nth state.

To me, i cant see how the energy here is dependent on time. I have seen a question in a textbook asking for the average energy at say time t=t_0. How would one approach this?

Am I missing something here?

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# Time dependence of energy & probability

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