A recent study conducted by researchers from the University of Geneva has provided significant insights into the behavior of dark matter. The findings indicate that dark matter behaves similarly to ordinary matter under the influence of gravity, challenging previous assumptions about its unique properties. Published in Nature Communications, this research offers a more detailed understanding of dark matter, which constitutes approximately five times the amount of ordinary matter in the universe.
Dark matter, an invisible and elusive component of the cosmos, has long puzzled scientists. It does not emit or reflect light, making it difficult to study directly. The research team, led by associate professor Camille Bonvin, aimed to explore whether dark matter is influenced by the same gravitational laws that govern ordinary matter. Their investigation centered on whether dark matter falls into gravitational wells—regions of space distorted by massive celestial bodies—in the same manner as stars and galaxies.
Comparative Analysis of Galactic Motion
To assess this, the researchers compared the velocities of galaxies with the depths of gravitational wells. According to Bonvin, “If dark matter is not subject to a fifth force, then galaxies—which are mostly made of dark matter—will fall into these wells like ordinary matter, governed solely by gravity.” Alternatively, if a fifth force were to influence dark matter, it would alter the motion of galaxies significantly.
The research team applied current cosmological data to their analysis and concluded that dark matter does indeed fall into gravitational wells similarly to ordinary matter, adhering to established physical laws, including Euler’s equations. This conclusion, while illuminating, does not entirely dismiss the possibility of an unknown force acting on dark matter. As noted by Nastassia Grimm, the study’s first author, “If such a fifth force exists, it cannot exceed 7% of the strength of gravity—otherwise it would already have appeared in our analyses.”
Implications for Future Research
These findings mark a crucial advancement in understanding dark matter’s characteristics. The next phase of research will focus on determining whether a fifth force influences dark matter. Upcoming experiments, such as the Large Synoptic Survey Telescope (LSST) and Dark Energy Spectroscopic Instrument (DESI), are expected to provide further insights. As highlighted by Isaac Tutusaus, a co-author and researcher at the Institute of Cosmology and Gravitation, “These data will be sensitive to forces as weak as 2% of gravity, potentially deepening our understanding of dark matter.”
As the scientific community continues to explore these complex interactions, the findings from the University of Geneva pave the way for future investigations into the fundamental properties of dark matter and its role in the universe. The ongoing quest to unravel the mysteries of this invisible substance remains a top priority for physicists worldwide.
For more detailed information, refer to the study by Grimm et al., titled “Comparing the motion of dark matter and standard model particles on cosmological scales,” published in Nature Communications in 2025.
