Changes

938 bytes added ,  21:25, November 22, 2016
Added stuff about probability
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Other examples include energy and time, as well as different components of [[angular momentum]].
 
Other examples include energy and time, as well as different components of [[angular momentum]].
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===Probability===
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The probability a particle is found in a certain region <math>a < x < b</math> can be described as:
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<math>
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p(a < x < b) = \int^b_a |\Psi (x,t)|^2 dx
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</math>
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provided that the wavefunction is normalised:
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<math>
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\int^\infty_{-\infty} |\Psi (x,t)|^2 dx = 1
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</math>
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In general, the expected value of a measurement of a quantity <math>Q</math> can be described as:
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<math>
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\langle Q \rangle = \int^\infty_{-\infty} \Psi^{*} \hat{Q} \, \Psi dx
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</math>
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where <math>\hat{Q}</math> is the [[operator]] associated with the quantity <math>Q</math>. For example the position operator is simply <math>x</math>. The [[momentum (physics)|momentum]] operator is:
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<math>\hat{p} = \frac{\hbar}{i} \frac{\partial}{\partial x}</math>
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so that the expected momentum is:
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<math>\langle p \rangle = \int^\infty_{-\infty} \Psi^{*} \hat{p} \, \Psi dx = \frac{\hbar}{i} \int^\infty_{-\infty} \Psi^{*} \frac{\partial \Psi}{\partial x} dx
    
==Interpretations==
 
==Interpretations==