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arXiv · 2506.24011

The Lifespan of our Universe

Hoang Nhan Luu·Yu-Cheng Qiu·S. -H. Henry Tye
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Abstract

The Dark Energy Survey (DES) and the Dark Energy Spectroscopic Instrument (DESI) measurements claim that the dark energy equation of state $w \ne -1$. This observation can be explained by the axion Dark Energy (aDE) model of an ultralight axion plus a cosmological constant $\Lambda$. Despite a relatively large degeneracy, there is a high probability that $\Lambda <0$. This negative $\Lambda$ leads the universe to end in a big crunch. Using the best-fit values of the model as a benchmark, we find the lifespan of our universe to be 33 billion years.

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Hoang Nhan Luu, Yu-Cheng Qiu, S. -H. Henry Tye. 2025-06-30. The Lifespan of our Universe. https://arxiv.org/abs/2506.24011

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