Explain Gravity to me.

[Q5Quint]

I have a few friends that are elementary school teachers. I will see if I can stir up some excellent drawings from 3rd graders explaining this juicy topic.

There was a great article in a scientific american or some journal thing about 'the unified theory of everything'. Something about higgs-bosons and quarks and up-your-bum-neutrinos in your root beer float. Makes for pretty spiro-graph type of pictures and apparently has something to do with gravity.

http://en.wikipedia.org/wiki/An_Exceptionally_Simple_Theory_of_Everything


And to keep this thread on track: an excellent picture of Stephen Hawking.

[be34st]

it's hard to understand because we're used to thinking in three dimensions.

Space is essentially empty. There are small collections of matter interspersed throughout called galaxies, in the galaxies are stars, formed of elements (hydrogen, helium mostly undergoing nuclear fission, other matter, nuclear energy from proton/neutron interaction). This energy disrupts the normally empty space, and causes nearby matter to be attracted to the disruption. The best analogy is stretching a bedsheet tight, placing a bowling or something heavy in the middle, and throwing a golfball across the sheet.. the golfball will circle the heavier object until they collide. You just have to replace the linear 2d example of the bedsheet as space-time with the reality (3d) and that's basically how I've heard it explained.

But I thought matter (molecules) has a tendency to move from high to low pressure 'areas'. With space having low pressure (almost in-existent), and the "disruption-of-empty-space" area having higher pressure due to the energy released by the interaction of these molecules, I don't see how matter would be attracted to this disruption. I'm no rocket scientist though, am I missing something?

edit: my brain hurts now