Dark matter, the enigmatic substance that makes up about 27% of the universe, may not be as invisible as once thought. While its existence is inferred from its gravitational effects on galaxies and clusters, scientists have yet to directly observe it. A few faint particle interactions have been detected, but they account for only a tiny fraction of the mystery.

Researchers at the University of York suggest a new approach: dark matter could leave subtle “fingerprints” on light. Their study, published in Physics Letters B, proposes that as starlight passes through dark matter, it could acquire a faint red or blue tint depending on the type of dark matter it encounters.

Figure 1. ‘Fingerprint’ on Starlight.

A Potential ‘Color Signature’ of Dark Matter

This theoretical work challenges the long-standing belief that dark matter does not interact with light. Dr. Mikhail Bashkanov of the University of York explains, “Most researchers would agree that dark matter is dark, but we have shown that even the darkest type could still have a kind of color signature. Under certain conditions, this ‘color’ might actually be detectable.” Figure 1 shows ‘Fingerprint’ on Starlight.

With advanced next-generation telescopes, scientists might measure these subtle shifts in light, opening a new avenue to study dark matter and better understand its composition.

The York team’s study is theoretical and draws on a concept they call the “six handshake rules,” suggesting that even if dark matter doesn’t directly interact with light, other particles could mediate the effect, leaving a detectable footprint [1]. Candidate dark matter particles, such as weakly interacting massive particles (WIMPs), might influence light indirectly through interactions with particles like the top quark or Higgs boson.

Searching for the Universe’s Hidden Mass

Dark matter was first proposed in the 1930s and is thought to account for roughly a quarter of the universe’s total mass, with dark energy driving the universe’s accelerating expansion. In 1998, the DAMA experiment in Italy claimed to detect dark matter in the form of WIMPs, though results remain unconfirmed.

Today, billions are being invested in experiments to detect WIMPs, axions, and dark photons. Dr. Bashkanov believes the York study could help focus these efforts: “Our results suggest we can narrow down where and how we should look in the sky, potentially save time and guide the search for dark matter more efficiently.”This new approach could bring astronomers closer than ever to unraveling one of the universe’s greatest mysteries.

Reference:

1. https://interestingengineering.com/space/dark-matter-might-interact-with-light

Cite this article:

Keerthana S (2025), Scientists Suggest Dark Matter Could Leave a Distinct ‘Fingerprint’ on Light, AnaTechMaz, pp.557