Proving 2<T> = <x\frac{dV}{dX}> and Virial Theorem

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Homework Statement



I must prove that:

\frac{d}{dt}&lt;xp&gt; = 2&lt;T&gt; - &lt;x\frac{dV}{dX}&gt;

And use the virial theorem to prove that &lt;T&gt; = &lt;V&gt;




Homework Equations



2&lt;T&gt; = &lt;x\frac{dV}{dX}&gt;

\frac{d}{dt}&lt;Q&gt; = \frac{i}{h(bar)}&lt;[H, Q]&gt; + &lt;\frac{\partial Q}{\partial t}&gt;

Where Q on the right side is an operator, as well as H.



The Attempt at a Solution



Do I just plug in \frac{d}{dt}&lt;xp&gt; into the general equation?

Thanks.
 
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In the second equation that you posted, replace Q with xp and H with

-\frac{\hbar^2}{2m}\frac{\partial^2}{\partial x^2}+V(x)

and expand the commutator.
 
To solve this, I first used the units to work out that a= m* a/m, i.e. t=z/λ. This would allow you to determine the time duration within an interval section by section and then add this to the previous ones to obtain the age of the respective layer. However, this would require a constant thickness per year for each interval. However, since this is most likely not the case, my next consideration was that the age must be the integral of a 1/λ(z) function, which I cannot model.
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