پایای ِ جنبش pâyâ-ye jonbeš
*Fr.: constante de mouvement*
1) *Classical mechanics*: A variable *X* whose total rate of change *dX/dt*
along the path of a → *dynamical system* is zero. In other words,
a function of an object's position, velocity, or both that does not change even as the
object moves. For example, the total energy of a
→ *simple harmonic* oscillator is a constant of the motion.
2) *Quantum mechanics*: An → *observable*
that remains constant in time. As an example, the energy
is a constant of the motion of all systems whose → *Hamiltonian*
does not depend explicitly upon time. → *constant*; → *motion*. |