In a new study published in Physical Review Letters, scientists have discovered a novel approach to detecting the quantum properties of a system by simply using heat as a witness, requiring no direct measurement of the quantum system itself.

The study proposes connecting thermodynamics with quantum information theory, drawing inspiration from the concept of Maxwell’s demon.

The concept proposed in the 19th century involves an imaginary entity, Maxwell’s demon, that can sort gas molecules by their velocities inside a closed box, seemingly violating the second law of thermodynamics.