What is the time derivative of a quantum observable? Academic Article uri icon


  • A reasonable-sounding prescription for measuring dA dt is to measure A itself at times t and t + Δt and to calculate [A(t + Δt) - A(t)] Δt {reversed tilde equals} dA dt, with Δt sufficiently small. However, this interpretation is shown to be untenable if dA dt is defined by the Heisenberg equation of motion for A. Thus a phenomenon noted by Ruijsenaars for the position and velocity observables of a relativistic particle is actually a general feature of quantum theory. © 1985.

author list (cited authors)

  • Fulling, S. A.

citation count

  • 0

complete list of authors

  • Fulling, SA

publication date

  • October 1985