If the big bang happened 13.8 billion years ago, and the universe is 93 billion light years in diameter, how did the universe expand faster than light?
In: Physics
Imagine the universe like the surface of a balloon. This universe has an incredibly slow speed limit of 1 centimeter per hour over its surface. The balloon is also inflating so that two dots that are sitting still on the surface are actually moving apart faster than 1 cm per hour.
That’s what the universe is doing, except in 3 dimensions instead of 2. The really crazy thing is that the expansion is *accelerating*, and we don’t know exactly why.
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