👉 "Unexpanding" in physics refers to a physical quantity that does not change in response to an increase or decrease in another quantity. It is often used in the context of quantum mechanics, where it describes the behavior of particles (like electrons) as they move through space and time. The term "unexpanding" can also refer to a situation where a system is experiencing no net external force acting on it. This is analogous to an object that is not being acted upon by any external forces
