What is the temperature at the point where the universe is expanding?

1 Answer
Nov 15, 2017

Very similar to the rest of the universe, I think, at 2.73 K (minus #270^@C#)

Explanation:

If the universe were expanding into something then one might suppose there would be a shock wave/interface where temperatures might rise, but in fact it is space itself that is expanding. By definition there is nothing outside the universe (the word literally means ‘one thing’)