Suppose I'm considering particles of mass [itex]\mu_i[/itex], [itex]1 \leq i \leq 3[/itex], located at positions [itex]r_i[/itex]. Suppose I ignore the potential between [itex]\mu_1[/itex] and [itex]\mu_2[/itex]. Then the Hamiltonian I'd write down would be(adsbygoogle = window.adsbygoogle || []).push({});

[tex]

H = -\frac{1}{2\mu_1}\Delta_1 -\frac{1}{2\mu_2}\Delta_2 - \frac{1}{2\mu_3}\Delta_3 + V_1(r_3 - r_1) + V_2(r_3 - r_2).

[/tex]

But what if I instead want to work in a frame of reference in which [itex]\mu_1[/itex] is at rest? How should I go about changing [itex]H[/itex]? I'm never very sure of myself when I do these kinds of calculations, so any help would be appreciated...thanks!

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# Changing the Hamiltonian to a new frame of reference

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