I am not sure to put this in this secton or computer section

[billa12]

Can quantum computers simulate quantum effects and non quantum effects in one program? If not will they be able to in the future?

Can a classical computer simulate quantum mechanics?

 

[jedishrfu]

Classical computers have been used to simulate many types of physical systems including quantum mechanical systems with varying degrees of accuracy.

To learn more about computational physics you can browse the open source physics website at www.compadre.org/osp

All digital computers follow the Turing model hence even a quantum computer should be able to simulate the same systems as a classical computer. The hope is that they will be many times faster allowing to simulate to greater detail and get more accurate predictions.

In contrast, some systems can be better simulated using an electrical analog computer (analog circuit connected to an oscilloscope) many times faster than a classical computer although the degree of accuracy may be limited. As an example a calculator can provide many digit accuracy vs a slide with at most 3 to 4 significant figures.

 

[Zarqon]

When you say "simulate" I assume that you mean "efficiently simulate", since the problem with classical computers is that we have not found any way to efficiently (using only polynomial resources) simulate quantum physics. Quantum computers however, can always simulate both quantum and classical physics, because there is no problem at all letting a quantum bit be a normal bit, by just ignore the phase/superposition possibilities.

Though note that we are not yet there when quantum simulators can do stuff that classical can't, we still need more qubits to outperform classical simulators.