I'm looking for examples in the human body which show periodicity, more precisely, I'm looking for examples of oscillating reactions that occur in the human body which can be modelled using the Hamiltonian of the harmonic oscillator. for example, as someone mentioned to me before, the circadian rhythm is controlled by the oscillation of protein concentration. I wanted to know if there are some examples from biologists perspective?
I want to read more about it, and I will be grateful to hear more examples so I can look for information about it online or if anyone could refer me to some reading material regarding this subject.
Thank you very much for your time and attention.