The quantum Ruijsenaars model is a q-analogue of the Calogero—Moser model, described by n commuting partial difference operators (quantum hamiltonians) h_1, …, h_n. As it turns out, for each natural number l>1 there exists another integrable system whose quantum hamiltonians have the same leading terms as the l-th powers of h_1, …, h_n. I will discuss several ways of arriving at this generalisation.
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