Hysteretic phenomena are often linked to dissipation. When there is a hysteresis loop, the dissipated energy can usually be computed as the area of the cycle.
For example, in ferromagnetic materials, the relationship between the magnetization and the magnetic field can exhibit a hysteresis loop, corresponding to the microscopic dissipation by Joule effect; in elastic materials, there is a hysteresis in the relation between the constraint and the extension, corresponding to the internal friction.
There are lots of other examples where I do not know exactly the dissipation processes: in all first-order phase transitions (e.g. liquid-gas), in the contact angle, and so on. I feel like hysteretic phenomena cannot appear without dissipation, because hysteresis needs memory as well as the possibility to lose this memory (which is an irreversible process). However, perhaps I miss some other possibility.
So, is hysteresis always linked to dissipation? Is it due to irreversibly? Is there a means to prove that formally?
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