Dark matter is physics’s equivalent of fossil bacteria on Mars. What if it doesn’t exist? Not even one particle…? An astrophyscist speculates.
The notion that gravity behaves differently on large scales has been relegated to the fringe since Rubin’s and White’s heyday in the 1970s. But now it’s time to consider the possibility. Scientists and research teams should be encouraged to pursue alternatives to dark matter. Conferences and grant committees should allow physicists to hash out these theories and design new experiments. Regardless of who turns out to be right, such research on alternatives ultimately helps to crystallise the demarcation between what we don’t know and what we do. It will encourage challenging questions, spur reproducibility studies, poke holes in weak spots of the theories, and inspire new thinking about the way forward. And it will force us to decide what kinds of evidence we need to believe in something we cannot see …
Hundreds if not thousands of astrophysicists, astronomers and particle physicists now study every aspect of dark matter and every imprint it might have on the cosmos, with state-of-the-art computers, telescopes and particle accelerators. Dark matter research has dwarfed modified gravity research for decades, but it doesn’t necessarily mean that dark matter is that much more convincing a theory. Instead, early on, some scientists thought it was a natural solution, others followed their view, and the scales tilted to their side.
Today’s seeming dominance of dark matter wasn’t inevitable. The processes through which scientists develop theories are heavily influenced by all sorts of historical and sociological factors, a point eloquently made by Andrew Pickering, emeritus philosopher of science at the University of Exeter and the author of Constructing Quarks (1984), a 36-year-old book that’s still relevant today. Ramin Skibba, “Does dark matter exist?” at Aeon