Dark Energy Cancelled?
Einstein never liked the cosmological constant. He added it to General Relativity to preserve a static universe, which was the accepted cosmological paradigm in the early 1900s. When astronomers discovered the expansion of observed galaxies, with velocities proportional to their redshifts, he was delighted to get rid of the CC which he regarded as blemish on the elegance of General Relativity.
However, subsequent theoreticians kept trying to resurrect the CC in order to explain problematic observations and/or theoretical shortcomings. The latest reincarnation of the CC has been as an explanation for the accelerated expansion that was discovered a couple of decades ago and dubbed Dark Energy.
Now researchers at the University of Copenhagen have found that Dark Matter objects with magnetic properties could explain the observed accelerated expansion without any need for Dark Energy. These researchers only considered DM particles, but another DM candidate is also possible.
If the Dark Matter is composed of stellar-mass primordial Kerr-Newman black holes, defined by their mass, spin and charge, then they could generate the electromagnetic phenomena required to explain the accelerated expansion. Black holes are commonly observed, and do not require hypothetical particles with putative properties.
Here is the short version: https://www.sciencedaily.com/releases/2021/03/210331103624.htm
And here is the link to the full paper: https://arxiv.org/abs/2102.07792