A new theory proposed by a physicist from the University of Ottawa challenges the long-held belief that dark matter and dark energy are fundamental components of the universe. The proposal suggests that these invisible forces may not exist at all but are illusions caused by changes in the fundamental forces of nature over time. For more than thirty years, cosmologists have operated under the assumption that about 95% of the universe is composed of two mysterious entities: dark matter, which exerts gravitational pull without emitting light, and dark energy, which appears to accelerate the universe’s expansion.
These ideas have become key pillars of the standard cosmological model, guiding both theoretical development and large-scale experimental searches. Now, physicist Rajendra Gupta proposes a radically different perspective. In his latest research, he attributes the cosmic phenomena usually linked to dark matter and dark energy to a much simpler mechanism: the gradual weakening of the universe’s fundamental forces over time.
This approach removes the need for unknown particles and instead reinterprets well-documented observations through evolving physical constants. One of the most compelling aspects of Gupta’s model is its ability to link two major sets of astronomical observations under a single framework. On cosmological scales, where the universe appears largely uniform across hundreds of millions of light-years, dark energy has been used to explain its accelerating expansion.
Meanwhile, on smaller, clumpier scales—such as galaxies and galaxy clusters—dark matter is invoked to explain the extra gravitational forces needed to hold structures together. Gupta’s theory proposes that these seemingly unrelated phenomena can be described by a single equation involving a variable parameter known as α, which reflects the evolving strength of nature’s fundamental forces. “Ours is the only one that explains them with the same equation and without the need for dark matter or dark energy,” he said.
This parameter is adjusted based on the scale being observed—treated as constant at the cosmological level, and allowed to vary within galaxies where matter distribution is more complex. One of the long-standing anomalies in astrophysics has been the rotation curves of galaxies. Observations show that stars on the outer edges of galaxies rotate much faster than expected based solely on the visible mass.
Evolving forces reshape cosmic understanding
Traditionally, this discrepancy has been explained by proposing massive halos of dark matter surrounding galaxies. Gupta’s model challenges that interpretation.
As detailed in his research, it suggests that the variations in α, driven by the non-uniform distribution of ordinary matter, generate additional gravitational effects. These effects mimic the presence of dark matter without requiring any unseen mass. Where matter is densely packed, the added gravity is minimal.
But in sparser regions, the gravitational effect is enhanced, accurately reproducing the flat rotation curves observed in many galaxies. This approach not only provides a simpler explanation for a key phenomenon, but it also maintains consistency with the laws of physics already known, without introducing unverified entities. Another consequence of this new model lies in its impact on the timeline of the universe.
Recent observations have revealed galaxies and supermassive black holes forming earlier in cosmic history than current theories can comfortably explain. This has led to speculation about new types of matter or unknown physical processes. By incorporating the gradual weakening of forces into cosmic evolution, Gupta’s framework extends the effective age of the universe, allowing more time for large structures to form.
This means “there is no need to assume any exotic particle or break the laws of physics.” It offers a revised chronology that better aligns with the rapid appearance of galaxies in the early universe, avoiding the need for dark energy-driven acceleration or dark matter-driven clustering. The proposal, while still in its early stages, invites a reevaluation of the assumptions underpinning contemporary cosmology. It suggests that the elusive components scientists have been hunting for decades might be conceptual artifacts rather than actual constituents of the cosmos.
Whether this new interpretation will stand up to further scrutiny remains to be seen. But as Gupta himself concludes, “perhaps the universe’s greatest secrets are just tricks played by nature’s evolving constants.”
