I've read that scientists put together the temperatures of the tropics, geothermal vents, the Arctic, the Antarctic, etc to arrive at 15 degrees Celsius for Earth's average temperature. If you add up the temps inside stars, on planets, and in space at all times; do we have any idea what the average temperature of spacetime might be?
(I agree with Einstein's 1919 paper asking if gravitation and electromagnetism play a role in the constitution of elementary particles ... logically including the bosons of the weak and strong nuclear forces. Therefore, the stars and planets are regarded as unified with spacetime itself.)