For 10 points, name this principle which states that one cannot simultaneously determine both the position and momentum of a particle with arbitrary accuracy.
Leonid Mandelstam and Igor Tamm first formulated a variant of this relation for a system's time evolution and energy. The ground state of a system cannot be zero because this relation forbids the simultaneous minimization of both the potential and kinetic energy. Thus, this relation implies that a wave function's extension is, exponentially, inversely proportional to its kinetic energy. The wavelength of a photon determining the amount of diffraction is used to illustrate this relation in a thought experiment involving a (*) microscope, proposed by its formulator. This principle is often stated as the commutator of two certain variables being greater than or equal to h-bar over two. For 10 points, name this principle which states that one cannot simultaneously determine both the position and momentum of a particle with arbitrary accuracy.
Leonid Mandelstam and Igor Tamm first formulated a variant of this relation for a system's time evolution and energy.
Heisenberg uncertainty principle [or Heisenberg uncertainty principle; or "relation" in place of "principle"]