This kind of nonsense really gets to me. He wasn't the first to propose the universe could be expanding. The Friedmann cosmological metric predicts the universe could be expanding, static, or contracting. The first cosmological metric of GR. He didn't discover the universe was expanding. It was Edwin Hubble, the astronomer, that DISCOVERED the universe is expanding. That's why he gets the credit. I was responding to the 'wiki thing' somebody linked.