🔬 Sciencepublished 2w ago
The night sky is dark because the universe had a beginning
If the universe were static, eternal, and filled with an infinite sea of stars, the night sky would blaze with blinding light, because every line of sight would eventually hit a stellar surface. The darkness between stars—known as Olbers' paradox—proves that the universe had a beginning. Because the cosmos is only 13.8 billion years old, light from the most distant stars has simply not had enough time to cross space and reach our eyes.
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