I am used to symmetry breaking in condensed matter, where we have a preferred reference frame (superconductivity, ferromagnets, etc). But what about Lorentz symmetry? What would such symmetry breaking look like? The intuition tells me the resulting system should look like a superfluid, where there is a continuum of ground states which can be transformed into one another by boosts, and the spectrum of excitation inside such superfluid does not have to be Lorentzian. Would this be a correct intuition?
Also, can it be we are living in a world with such broken Lorentz symmetry (since there is a preferred reference frame associated with CMB)?
