Non existing in the real world but "Cosmologists" still don't know why Einstein called it ''"the biggest blunder of my life"''.
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Non existing in the real world but [[relativists]] still don't know why Einstein called it ''"the biggest blunder of my life"''. Just know that he did.
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Couldn't figure it out why though<ref>Misner, Thorne, and Wheeler, 1973, ''"Gravitation"'', page 410.</ref>. They use it as "[[dark matter]]".