I understand it is quite a bit to take in. Here I thought you could take it all in.

"All this invisible matter and energy makes my head hurt."

"No I can, I swear!"

Good! Glad to hear it. There is this thing called The Hubble Constant. And believe it or not, it helps estimate the size and age of the universe. It indicates the rate at which the universe is expanding. The only problem is that it often has a subscript to denote that it was at that rate in the present time.

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