Role of simulation

Computer simulation in general, and molecular dynamics in particular, represent a new scientific methodology. Instead of adopting the traditional theoretical practice of constructing layer upon layer of assumption and approximation, this modern alternative attacks the original problem in all its detail. Unfortunately, phenomena that are primarily quantum mechanical in nature still present conceptual and technical obstacles, but, insofar as classical problems are concerned, the simulational approach is advancing as rapidly as computer technology permits. For this class of problem, the limits of what can be achieved remain well beyond the horizon.

Theoretical breakthroughs involve both new concepts and the mathematical tools with which to develop them. Most of the major theoretical advances of the just-finished twentieth century rest upon mathematical foundations developed during the preceding century, if not earlier. Whether still undeveloped mathematical tools and new concepts will ever replace the information presently only obtainable by computer simulation, or whether the simulation is the solution, is something only the future can tell. Whether computer modeling will become an integral part of theoretical science, or whether it will continue to exist independently, is also a big unknown. After all, theory, as we know it, has not been around for very long.

To what extent can simulation replace experiment? In the more general sense, this is already happening in engineering fields, where models are routinely constructed from well-established foundations.