Active galaxies point to new physics of cosmic expansion

[wolram]

https://phys.org/news/2019-01-galaxies-physics-cosmic-expansion.html

can dark energy vary over the history of the universe?

 

[PeterDonis]

can dark energy vary over the history of the universe?

So far the mainstream belief is that it doesn't. But it's still an open area of research, as the article you linked to shows. Since it's an open area of research, a final answer is not known.

 

[PeterDonis]

The OP question has been answered. Thread closed.