06/04/2019
Watching the waterfall made me wonder why gravity only pulls water "down." The other three strong, weak, and electromagnetic forces can all repel, and pull like the way a magnet can either stick to another magnet, or be pushed away but why can't gravity push? I guess it makes sense the same way that you can't count a negative amount of any physical object because what is a negative object? The other three forces are all reliant on positive and negative charges where opposites attract, but the theroretical particles called gravitons that are responsible for gravity respond only to energy density, which can only be positive. Or can it? The physical matter you interact with every day is only occupying 5% of the mass of the universe, which means the vast majority of what makes up the universe is called dark matter and energy. This was explained when physicists tried to calculate the distribution of mass in the universe and normal matter didn't explain why there is enough gravity in galaxies to cause them to look the way they do. So, there is an elementary particle that we cannot see, measure, or interact with in any way, but we're pretty sure it's there, because of the way space is continually expanding at an increasing rate as measured by Hubble's red-shift discovery. This idea then would show that in fact gravity does have a repelling force as well as an attractive one. I think it's a bizzare and fascinating idea that changes the way I understand intuitively what gravity is.
