👉 "Costman" is a term used in the context of the field of physics and quantum mechanics. It refers to an operator that describes how energy is transformed between two different states. In simpler terms, it represents a mathematical function that maps a state (represented by its wavefunction) to another state (the expectation value of the energy operator). The concept of costman was introduced in 1927 by physicist Richard Feynman and has since been widely studied in the field of quantum physics
