In Expanding de Sitter Space, Quantum Mechanics Gets Even More Elusive

In theory, a universe can come in any shape or size, but scientists prefer to think about three basic kinds of universes: one that’s expanding, one that’s collapsing, and one that stays the same. Out of these three simplified models, an expanding universe is the hardest for physicists to understand. Yet it’s exactly the one our real world most resembles. When physicists calculate what’s going on…

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