The universe is flat — to within 0.4% precision — and nobody fully understands why
Some trivia is so bizarre it forces you to rethink your entire understanding of the world. Check out the fact below, see how others reacted, and scroll down to dive into the verified science and history behind it.
In cosmology, the "shape" of the universe refers to its spatial curvature. It could be positively curved (like a sphere), negatively curved (like a saddle), or flat (like a sheet of paper). Measurements of the cosmic microwave background radiation — the afterglow of the Big Bang — show the universe is geometrically flat to within 0.4% accuracy. This requires the total energy density of the universe to be almost exactly at the critical value. The precision is so extreme that physicists call it the flatness problem: it looks designed.
The universe being flat to this precision is like throwing a dart from 300km away and hitting a bullseye smaller than an atom.
The Science Behind It
In cosmology, the "shape" of the universe refers to its spatial curvature. It could be positively curved (like a sphere), negatively curved (like a saddle), or flat (like a sheet of paper). Measurements of the cosmic microwave background radiation — the afterglow of the Big Bang — show the universe is geometrically flat to within 0.4% accuracy. This requires the total energy density of the universe to be almost exactly at the critical value. The precision is so extreme that physicists call it the flatness problem: it looks designed.
Why Your Brain Finds This Hard to Believe
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