Gravity controls the universe — at least on a large scale. Obviously, gravity keeps you and your possessions from floating away into space. Gravity also holds planets and stars together. It holds the Moon in orbit around the Earth and all of the planets in orbit around the Sun. Gravity holds the galaxies together. But other forces are stronger than gravity.
Four interactions make the universe work: the weak and strong nuclear forces, electromagnetism, and gravity. Gravity is by far the weakest of those forces. The weak and strong nuclear forces are limited to a very short range within the atom. Only the electromagnetic force and gravity reach out to the vast universe. Since the electromagnetic force is so much stronger than gravity, why does gravity control the universe?
Everything is made of atoms and atoms contain electrons and protons. Electrons have a negative charge, and protons have an equal and opposite positive charge. Electromagnetism causes opposite charges to attract and like charges to repel each other. Gravity, of course, pulls anything with mass together.
The reason electromagnetism does not overpower the much weaker force of gravity is a delicate balance between electrons and protons. For each electron in the universe, there is a proton, so the plus and minus electrical forces cancel each other, creating electrical neutrality. Without that balance, we could not exist.
The balance between electrons and protons is so delicate that if you were building a universe and accidentally put in one extra electron for each trillion trillion trillion electron/proton pairs (that’s one followed by 36 zeroes), it would be catastrophic. The electrical repulsion between those negatively-charged electrons would overpower the gravitational force. The result would be that gravity could not pull any mass together. If gravity could not pull masses together, there would be no planets, no stars, no galaxies. Electromagnetic repulsion would create a universe of dispersed particles and nothing else.
Each of the other forces is stronger than gravity. The weak and strong nuclear forces are confined to short distances within the atom, and the electromagnetic force is carefully balanced. Is it possible that this precision is merely an accident? Or do we see evidence of system design? We think this is one more example of fine-tuning in the universe which gives evidence of a Designer.
–Roland Earnst © 2018