Undergrad Hamiltonian formalism and partition function

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In Hamiltonian formalism, generalized coordinates and conjugate momenta are crucial for describing systems. For a dipole in a magnetic field, the Hamiltonian is defined as H = -μB cos(θ), where θ is the angle between the dipole moment and the magnetic field. Both θ and cos(θ) can be treated as generalized coordinates, with the associated conjugate momentum Pθ linked to angular momentum. This approach is essential for computing the partition function for the dipole system using the integral formulation. Understanding these relationships is key to analyzing the thermodynamic properties of the dipole in the magnetic field.
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is it possible to find a (q,p) couple for a dipole in a magnetic field?
In hamiltonian formalism we have the generalized coordinates ##q_i## and the conjugates moments ##p_i##.
For a dipole in a give magnetic field ##B## the Hamiltonian is ##H=-\mu B cos \theta## where ##\theta## is the angle between ##\vec \mu## and ##\vec B##.
Can i consider ##\theta## or ##cos \theta## as a generalized coordinate? if yes what is the associated conjugate momentum ##P_\theta##?
I ask this question because i'd like to compute the partition function for a dipole in a magnetic field starting from ##\frac 1 {\hbar ^f} \int dr^fdp^f exp(-\beta H(r_1...r_f,p_1...p_f))##
 
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Either ##\theta## or ##\cos\theta## could be considered as a generalised coordinate. The corresponding canonical momentum would be related to angular momentum.
 
Topic about reference frames, center of rotation, postion of origin etc Comoving ref. frame is frame that is attached to moving object, does that mean, in that frame translation and rotation of object is zero, because origin and axes(x,y,z) are fixed to object? Is it same if you place origin of frame at object center of mass or at object tail? What type of comoving frame exist? What is lab frame? If we talk about center of rotation do we always need to specified from what frame we observe?

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