Basically the magnetic viscosity argument is rubbish. Sean's thought experiments the effects of neglect induction and the internal state of the magnets. To get an accurate description of what is happening, you need to look at the internal state of the magnet. At a microscopic level, there is no asymmetry, it only arises do to various spins being oriented in different directions. You can basically think of this as the domains growing and shrinking. This doesn't violate Noether's theorem, since the strength of the underlying physical interactions (i.e. magnetic dipole moments, etc.) are time invariant.
An easier way to see this is by going to quantum mechanics. If we consider the whole device, we can construct a Hamiltonian which describes the dynamics of the system. The eigenvalues of this Hamiltonian are taken to be the energy of various states, and if when the system starts in an eigenstate of the Hamiltonian, it does not evolve. This means it retains the same energy.
Actually, conservation of energy is essentially written into quantum mechanics when the Hamiltonian is time invariant (as it must be for elementary particles). The Hamiltonian is effectively the total energy operator. Since the evolution of any quantum system is given by the operator exp(-iHt), it is impossible to move form one energy to another.
Actually, if you look in the comment section of the post, nleseul gave me a few pointers about what Sean was talking about. He seems to be completely neglecting the microscopic description of the magnet, in favour of hand-wavy, deeply flawed, thought experiments.
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Basically the magnetic viscosity argument is rubbish. Sean's thought experiments the effects of neglect induction and the internal state of the magnets. To get an accurate description of what is happening, you need to look at the internal state of the magnet. At a microscopic level, there is no asymmetry, it only arises do to various spins being oriented in different directions. You can basically think of this as the domains growing and shrinking. This doesn't violate Noether's theorem, since the strength of the underlying physical interactions (i.e. magnetic dipole moments, etc.) are time invariant.
An easier way to see this is by going to quantum mechanics. If we consider the whole device, we can construct a Hamiltonian which describes the dynamics of the system. The eigenvalues of this Hamiltonian are taken to be the energy of various states, and if when the system starts in an eigenstate of the Hamiltonian, it does not evolve. This means it retains the same energy.
Actually, conservation of energy is essentially written into quantum mechanics when the Hamiltonian is time invariant (as it must be for elementary particles). The Hamiltonian is effectively the total energy operator. Since the evolution of any quantum system is given by the operator exp(-iHt), it is impossible to move form one energy to another.
Actually, if you look in the comment section of the post, nleseul gave me a few pointers about what Sean was talking about. He seems to be completely neglecting the microscopic description of the magnet, in favour of hand-wavy, deeply flawed, thought experiments.