Dark matter — an invisible substance that holds galaxies together like glue — remains the main cosmological mystery. Efforts to find it using traditional methods have reached an impasse. Against the backdrop of this crisis, physicist Stefano Profumo of the University of California, Santa Cruz, proposed two revolutionary, albeit speculative, scenarios for the origin of this mysterious matter.
Scientists discovered dark matter only because of its gravitational influence: galaxies rotate faster than they should, considering only visible matter. The difficulty lies in the fact that this mysterious substance does not emit or absorb light at all, making direct detection impossible. Decades of searching have been fruitless. Hypothetical particles that dark matter is supposed to consist of, such as WIMPs, have never been found. This deadlock forces scientists to seek radical alternatives, which may even be fantastical.
Mirror Universe
In his first article, Profumo addresses quantum chromodynamics, the theory of the strong nuclear force. He suggests the existence of a parallel “mirror” universe, where similar but invisible forces and particles — analogues of protons and neutrons — act. In the early Universe, the concentration of these dark particles could have been extremely high. This resulted in the formation of compact objects – dark matter black holes. They interact with our world exclusively through gravity, explaining the observed effects.
Birth on the edge
Profumo’s second article offers an even more exotic idea. He considers the cosmic horizon — the boundary of the observable Universe, similar to the event horizon of a black hole, but on a global scale. During the period of extremely rapid expansion of the Universe (inflation) after the Big Bang, quantum fluctuations at this cosmic horizon could spontaneously generate dark matter particles with a wide range of masses. These particles, born at the very edge of our existence, could also be a source of invisible mass.
Verification methods
“Both mechanisms are highly speculative,” Profumo notes, “but they offer self-sufficient and calculable scenarios that are independent of problematic traditional models.”
Although the theories are based on modern physics, they require significant refinement and verification in future experiments and observations. Despite this, Profumo’s work opens up new, bold avenues for unraveling one of the deepest mysteries of the cosmos — the nature of dark matter, which shapes our universe.
According to Science Alert
