eli5 If matter cannot be destroyed or created, how does space constantly expand?

Question

Maybe I’m misinformed about this. But I was always told matter cannot be destroyed or created. But I have been told space is constantly expanding. Is this expansion of space not made up of “matter”? Where does it come from?

In: 282

Answer 1

Things aren’t getting bigger. They are moving further apart. Galaxies all more or less fly outward from the center of the universe, because everything is debris flying away from the big bang.