Astronomy & Space Science · AST-673
Possible Futures of the Universe: Physical Mechanisms
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Mechanism
Mechanism of Possible Futures of the Universe
As expansion accelerates, distant unbound galaxies cross beyond causal reach while bound structures remain held together locally. Star formation declines as gas is consumed, stars evolve into remnants, and extremely long-timescale processes dominate.
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- 01The Big Bang — SummaryOpen source ↗
OpenStax Astronomy 2e · Mar 9, 2022
View claim-by-claim traceability3 verified claims
As expansion accelerates, distant unbound galaxies cross beyond causal reach while bound structures remain held together locally.
supported · checked Sep 22, 2026The long-term future of the universe depends on the behavior of dark energy, matter density, structure evolution, and particle physics.
supported · checked Sep 22, 2026Current observations favor continued acceleration consistent with dark energy close to a cosmological constant, but measurements of its equation of state and possible evolution remain important.
supported · checked Sep 22, 2026