  A strong analog classical simulation of general quantum evolution is
proposed, which serves as a novel scheme in quantum computation and simulation.
The scheme employs the approach of geometric quantum mechanics and quantum
informational technique of quantum tomography, which applies broadly to cases
of mixed states, nonunitary evolution, and infinite dimensional systems. The
simulation provides an intriguing classical picture to probe quantum phenomena,
namely, a coherent quantum dynamics can be viewed as a globally constrained
classical Hamiltonian dynamics of a collection of coupled particles or strings.
Efficiency analysis reveals a fundamental difference between the locality in
real space and locality in Hilbert space, the latter enables efficient strong
analog classical simulations. Examples are also studied to highlight the
differences and gaps among various simulation methods.
