In this clip from Genius by Stephen Hawking, learn about the uniform expansion of space. The volunteers take to the ice to try and replicate The Big Bang. To do this they use the help of an ice hockey team and leaf blowers with giant balloons to figure out how an expanding universe could work. The formation in which the hockey team inflate the balloon shows that the planets furthest from the center gained more speed and travelled a further distance. This demonstration shows that the universe expands via uniform expansion. It is not the galaxies that are expanding or accelerating but the space in between them. Objects in space such as galaxies and stars stay the same size; it's as if space is being stretched.