A hot magnetic system can actually cool down and freeze faster than one that starts out cold.
This phenomenon is known as the Mpemba effect and has been a debated paradox in physics for centuries. This study found that the effect is incredibly strong in certain quantum magnetic models where phase transitions occur. The hotter system takes a faster path through its internal states to reach its final cold temperature. This discovery links the speed of cooling to the way matter changes its fundamental state. It suggests that we can use heat to speed up certain quantum processes that are usually slow.
Strong Mpemba Effect Through a Reentrant Phase Transition
arXiv · 2604.28117
We investigate temperature quenches across the reentrant phase transition of the antiferromagnetic Ising model in a magnetic field and show that the strong direct and inverse Mpemba effects arise when quenches terminate in the paramagnetic phase. These anomalous relaxation phenomena originate from the selective excitation of the slowest relaxation mode, which in the paramagnetic phase is purely staggered. Consequently, quenches starting from the paramagnetic phase have zero overlap with the slow