the magnetothermal expansion of the material is modified all in response to the quantum critical fluctuations. Non-equilibrium quantum phase transition An intuitive guess of the effect of a quantum critical point being affected by noise would be that the external noise defines an effective temperature. This effective temperature would introduce a well defined energy scale in the problem and break the scale invariance of the quantum critical point. On the contrary, it was recently found that certain types of noise can induce a non-equilibrium quantum critical state. This state is out-of-equilibrium because of the continuous energy flow introduced by the noise, but it still retains the scale invariant behavior typical of critical points. Notes References Quantum phases Condensed matter physics