摘要：Water is one of the most abundant substances in the universe and affects every aspect of our lives. It shows many anomalies unlike from most of other materials. Not only water, but a group of substances with different chemical properties also share similar anomalous behaviors (e.g., density anomaly, diffusivity anomaly). Such anomalies were proposed to be caused by the existence of a hypothetical liquid-liquid critical point, which is usually buried deep in the supercooled region. Experimental confirmation is very difficult and challenging due to crystallization. In this talk, I will discuss the possible solutions to detect the critical point using equilibrium and non-equilibrium phase transition. We also discuss the possible connections between equilibrium and non-equilibrium phase transitions.