Subject: dark energy
We may have it wrong. Of course, dark energy is full of "mays" and speculation.

https://www.nytimes.com/2024/0...

Dark energy was assumed to be a constant force in the universe, both currently and throughout cosmic history. But the new data suggest that it may be more changeable, growing stronger or weaker over time, reversing or even fading away.

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The key words are “might” and “could.” The new finding has about a one-in-400 chance of being a statistical fluke, a degree of uncertainty called three sigma,

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When the researchers put it all together, they found that the usual assumption — a constant dark energy — didn’t work to describe the expansion of the universe. Galaxies in the three most recent epochs appeared closer than they should have been, suggesting that dark energy could be evolving with time.

Project DESI: https://www.desi.lbl.gov