Physics 451

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Physics 451

• Quantum mechanics I
• Fall 2009

Sep 16, 2009 Karine Chesnel
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Quantum mechanics
Announcements

• Homework this week
• Thursday Sep 17 by 7pm HW 4
• help session Thursday (Peter) 3- 6pm 393 CB

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Quantum mechanics Ch 2.2
Infinite square well
Properties of the wave functions yn
1.They are alternatively even and odd
2. Each successive state has one more node
3. They are orthonormal
0
a
x
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Quantum mechanics Ch 2.2
Infinite square well
Possible states and energy values
Quantization of the energy
Each state yn is associated to an energy En
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Quiz 7
Quantum mechanics

• 0

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Quantum mechanics Ch 2.2
Infinite square well
Expectation value for the energy
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Quantum mechanics Ch 2.2
Infinite square well
Expectation value for the energy
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Quantum mechanics Ch 2.2
Infinite square well
Normalization
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Quantum mechanics Ch 2.2
Infinite square well
How to find the coefficients cn?
Fouriers series expansion
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Quantum mechanics Ch 2.2
Infinite square well
How to find the coefficients cn?
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Quiz 8
Quantum mechanics
Could this function be a solution for the wave
function of a particle in an infinite square
well at a given time?
x
a
0

• Yes
• No