The standard cosmological model, critics argue, is built on unobserved phenomena like dark matter, but is defended by the mainstream despite mounting contradictions. However, physicist Martín López-Corredoira argues that there is no elusive dark matter particle waiting to be found that would explain the Big Bang. Instead, we may need a patchwork of explanations: modified gravity, baryonic matter, and contextual fixes. It’s time to abandon the search for a one-size-fits-all cosmic theory.

Our current picture of the cosmos is one of an expanding universe governed by gravity, born from a hot beginning and stretched uniformly across vast scales. But this vision only holds together when we invoke mysterious unseen forces—inflation, dark energy, and more. This prevailing cosmological model—also known as the Big Bang or Lambda-CDM (ΛCDM)—has countless problems, but it is mainstream, and almost all the scientific and economic efforts of the community of astrophysicists and theoretical physicists dealing with the question are focused on the search for evidence that can confirm it. Other models explaining the cosmos—for example those without a Big Bang beginning, without an inflationary period, without energy and dark matter—do not receive the same attention. But if any of them are correct, the cosmos could be very different from the mainstream version we have been taught as dogma.

The existence of dark or invisible matter detectable only through its gravitational influence has been known by astronomers for a long time now. In 1844, Friedrich Wilhelm Bessel argued that the observed proper motions of the stars Sirius and Procyon could be explained only in terms of the presence of faint companion stars. In 1846, Urbain Jean Joseph Le Verrier and John Couch Adams independently predicted the existence of Neptune based on calculations of the anomalous motions of Uranus. Le Verrier later proposed the existence of the planet Vulcan to explain anomalies in the orbit of Mercury, but he failed on that occasion because the solution was not invisible matter but a change of gravitational laws, as was solved years later by Einstein with General Relativity.

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In 1933, Swiss astronomer Fritz Zwicky was studying rich clusters of galaxies—large clusters containing hundreds or thousands of individual galaxies. He applied the virial theorem to calculate how much matter should be present based on the gravitational forces needed to hold these clusters together. There appeared to be about 60 times more matter than could be accounted for by all the visible stars and gas. In 1939, Horace W. Babcock first showed the need for dark matter for an individual galaxy by measuring how fast stars were rotating in the outer regions of the M31 galaxy, also known as Andromeda. The rotational velocity was faster than it should have been based on visible matter. At that time, however, the majority of astronomers were not yet convinced of the need for dark matter haloes in galaxies. They became more convinced in the 1970s with the rotation curves measured by Albert Bosma using radio telescopes and by Vera Rubin, William Kent Ford Jr., and Nortbert Thonnard using optical telescopes.