Scientists have questioned the existence of dark matter

For decades, scientists have been convinced that much of the universe is made up of dark matter and dark energy - mysterious substances that cannot be directly observed but which astronomers believe explain the accelerated expansion of the universe and the anomalous rotation of galaxies.

But a new study by Rajendra Gupta, an associate professor in the Department of Physics at the University of Ottawa, offers a revolutionary alternative: these entities may not exist at all.

According to Gupta, phenomena previously attributed to dark matter and dark energy can be explained without involving these hypothetical components. In his paper, published in the journal Galaxies, he argues that fundamental forces of nature, such as gravity, may be slowly weakening as the universe ages. This weakening is what leads to the observations that have previously been interpreted as evidence for the existence of dark matter and energy.

Gupta calls his model CCC+TL. It combines cosmological and astrophysical observations into a single theoretical framework. In his view, constants of nature (like the gravitational force) change over time and depend on a particular region of space. Such evolution explains:

• Flat rotation curves of galaxies (stars in the outskirts move faster than expected).

• Clustering of galaxies.

• Gravitational lensing (bending of light by massive objects).

One of the key parameters of the model is α. This parameter behaves as an additional component of gravity, creating an "extra force" effect, which in classical models was explained by the presence of dark matter. At the same time α is not something external - it simply reflects the variations of ordinary matter and the evolution of physical constants over time.

Dark energy as a side effect?

In standard cosmology, the accelerated expansion of the universe is explained by the action of some force called dark energy. But Gupta argues that the acceleration is just an illusion caused by the gradual weakening of fundamental forces. If the forces become weaker over time, it gives the impression that something is "pushing" galaxies away from each other.

On galactic scales, where matter is unevenly distributed, variations in the gravitational force lead to effects previously attributed to dark matter. Thus, a single model can explain both phenomena - the accelerated expansion of the Universe and the behaviour of galaxies - without the need to introduce dark components.If Gupta's theory is correct, it radically changes the understanding of the structure of the Universe. For example, it was previously considered a mystery how the universe could have massive galaxies and black holes so early in its existence. According to the new model, the time scale of the Universe is almost doubled, giving more time for large structures to form.

Moreover, the search for dark matter particles, on which billions of dollars have already been spent, may be unnecessary. Even if such particles are ever found, they would have to be six times the mass of all ordinary matter - which seems unlikely.

The simplest explanation is the best explanation

"Sometimes the simplest explanation is the best explanation," Professor Gupta concludes. - "Maybe some of the most puzzling mysteries of the cosmos are just the result of changes in the physical laws themselves as the universe ages."