Dark Matter: A Shadow World or Cosmic Leftovers?

Physicist Proposes Revolutionary New Theories

The universe’s hidden dark matter, a colossal enigma comprising 80% of cosmic matter, may originate from an unseen parallel realm or from the very fabric of the early universe, according to groundbreaking new research. These theories challenge conventional models and offer fresh perspectives on a persistent cosmic mystery.

The Shadow World Hypothesis

Physicist **Profumo** has put forth a compelling idea, published on July 8, 2025, in *Physical Review D*, suggesting dark matter could stem from a “shadow world.” This hypothetical realm mirrors our own, populated by dark counterparts to familiar particles like quarks and gluons. In this shadow universe, these dark particles might have coalesced into stable, microscopic black holes or similar compact objects in the universe’s infancy. These entities, interacting only through gravity, would remain invisible to light and standard matter detection, yet could account for the gravitational influence attributed to dark matter.

This concept builds upon the long-standing “mirror matter” theory, which posits a parallel universe with similar physics but complete separation from our own, detectable only by its gravitational pull.

Dark Matter as Early Universe Radiation

In a separate study published in May in *Physical Review D*, **Profumo** explored a drastically different origin for dark matter: radiation from the universe’s outer edge during its rapid expansion phase shortly after the Big Bang, known as the quasi–de Sitter phase. This theory applies quantum physics principles to the expanding cosmos, proposing that stable dark matter particles were effectively “frozen” from the thermal energy at the universe’s cosmic horizon.

The mass of these particles could vary significantly, from minuscule to extremely heavy, depending on the evolutionary path of the nascent universe. A key aspect of this theory is that it does not necessitate any interaction between dark matter and the particles described by the Standard Model of physics.

Challenging Conventional Wisdom

Profumo highlights the significance of these theories, stating, Both mechanisms are highly speculative, but they offer self‑contained and calculable scenarios that don’t rely on conventional particle dark matter models, which are increasingly under pressure from null experimental results. Unlike traditional models that depend on weakly interacting massive particles (WIMPs), which have yet to be detected, these new ideas leverage well-established physics principles extended into uncharted territory.

The ongoing search for dark matter faces significant hurdles, with the Large Hadron Collider’s experiments failing to detect WIMPs, leading to a re-evaluation of established theories. As of 2024, the absence of direct detection of WIMPs has intensified the search for alternative explanations for dark matter’s existence (CERN). While these new hypotheses are considered speculative, they represent innovative thinking that could lead to a breakthrough in understanding one of cosmology’s greatest mysteries. Future research aims to refine these concepts, underscoring the dynamic interplay between imaginative thought and fundamental physics in tackling complex scientific challenges.