alt Hacker NewsWe all know that life on Earth gets it's energy from the Sun.
But we also know that's an approximation we tell kids, really life gets low entropy photons from the Sun, does it's thing, and then emits high entropy infrared waste heat. Energy is conserved, while entropy increases.
But where did the Sun got it's low entropy photons to start with? From gravity, empty uniform space has low entropy, which got "scooped up" as the Sun formed.
EDIT: not sure why this is downvoted, is the explanation Nobel Physics laureate Roger Penrose gives: https://g.co/gemini/share/bd9a55da02b6
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This is just a question about the origins of inhomogeneity in the universe. The prevailing theory is cosmic inflation, I believe: in the early universe a quantum field existed in a high entropy state and then the rapid expansion of space magnified small spatial inhomogeneities in the field into large-scale structures. What we see as "low entropy" structures like stars are actually just high entropy, uniform structures at a higher scale but viewed from up close so that we can see finer-scale structure.
The photons do not have entropy.
The photons from Sun are hot, the space around Sun is cold, the system has a low entropy.
If the space around Sun was as hot as the photons, the entropy would be high.
But where did the Sun got it's low entropy photons to start with? From gravity, empty uniform space has low entropy, which got "scooped up" as the Sun formed.
Your question fascinated me. Googling "where did the Sun got its low entropy" I also came across these explanations:
"Solar energy at Earth is low-entropy because all of it comes from a region of the sky with a diameter of half a degree of arc."
also, from another reply:
"Sunlight is low entropy because the sun is very hot. Entropy is essentially a measure of how spread out energy is. If you consider two systems with the same amount of thermal energy, then the one where that energy is more concentrated (low entropy) will be hotter."
https://physics.stackexchange.com/questions/796434/why-does-...
Probably it's a bit of both. I'm not sure I understand your hypothesis about the Sun scooping up empty, low-entropy space. Wasn't it formed from dusts and gases created by previous stellar explosions, i.e. the polar opposite of low entropy?