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A quantum many-body system driven far from equilibrium via a parameter quench can show universal
dynamics, characterized by self-similar spatio-temporal scaling, associated with the approach to a non-thermal
fixed point [1–4]. Non-linear excitations such as solitons or vortices, rogue waves, and instantons play a key role
in the time evolution of such systems [5–8]. I will introduce to the concept of non-thermal fixed points and
discuss developing and decaying quantum turbulence, associated with an anomalous nonthermal fixed point,
exhibiting aspects equivalent as well as different from classical fluids [7]. A low-energy effective sine-Gordon
type represents a possible approach to the specific universality class of such anomalous fixed points,
characterized by sub-diffusive scaling [9,10].

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