density

You say constant density, which means it's actually increasing because space is increasing.

OK, so that’s density, and it’s a measurement that can go a long way in helping us understand changes in populations.

You have a certain density, let's start with that.

Some planets, like Jupiter and Saturn, they're really low density, and we know they're mostly made of hydrogen and helium.

So if there's another way, we know how to do it, to make that density thing with accelerators.

It has a mass and a size that gives us an average density.

I mean, if you concentrate it to the size of your thumb, well, then, you know, it's really the density that matters, the local density.