Hi all,(adsbygoogle = window.adsbygoogle || []).push({});

In my class we were given an assignment from Introduction to Quantum Mechanics by David Griffiths. The question is in Chapter 3, problem 3.34.

[PLAIN]http://img41.imageshack.us/img41/7899/prob334.png [Broken]

(The system has a harmonic oscillator potential.)

Right now I'm stuck with getting the probability for the measured energy values. I know that the probability is the square of the absolute value of the coefficients of the energy eigenstates. Based on the question, that would be:

[PLAIN]http://img59.imageshack.us/img59/3004/prob3341.png [Broken]

And since the measurements are obtained with equal probability:

[PLAIN]http://img14.imageshack.us/img14/3919/prob3342.png [Broken]

My question is, what are the coefficients? I know it would be 1 over the square root of 2, I'm just not sure of the sign. Wouldn't the square of the absolute value imply that there are positive and negative values?

[PLAIN]http://img508.imageshack.us/img508/7591/prob3343.png [Broken]

Thanks so much!

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# Homework Help: Probability in quantum mechanics

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