Dark matter is said to account for 85% of matter in the universe. Entering the scientific mainstream in the 1980s, it was key to explaining the otherwise anomalous speeds of stars and gas clouds in spiral universes. Yet decades of searching have so far revealed exactly zero dark matter particles. And now some cosmologists are starting to look for alternatives models of the universe that don’t posit dark matter, like MOND, to describe the world and effect a paradigm shift in our thinking about the cosmos.
Should scientists focus on one model of the universe when the dark matter it claims has never been directly discovered? Do we need a radical reassessment of our approach that would make it easier to question current accounts of cosmology? Or are we just around the corner from finally finding dark matter particles?