Re: Numbers
I guess it depends on what they wish to find out. For example, some experiments (simulations) can be done with a few particles that give Galaxies the shape we have, with some assumptions of dark matter/energy. For example that dark matter does not "collide" with normal matter. With a few particles, you see that they have specific orbits/locations. You can then see what values match our observations and assumed distributions.
I say assumes, as it's rather likely that dark matter is just a type of matter with weak/other interactions (Like photons have no mass, electrons have charge and neutrons pass through most things :P ), but there is some possibility it is in our understanding of gravity or some other system that is in error right not.
With some more info on Quantum Gravity, things might start to take shape.
Biting the hand that feeds IT
