- University of Sheffield scientists propose that dark matter exists alongside ‘dark photons’ in a hidden fifth dimension, where the dimension's geometry naturally enforces their masses into resonance (similar to a vibrating musical instrument)
- This ‘tuning’ could explain how dark matter could interact strongly during the formation of the universe while remaining virtually undetectable and inert today, eliminating the need for artificially fine-tuned physics models
- By connecting the mystery of dark matter with the concept of hidden dimensions, the theory could give physicists clear new targets in the search for the elusive substance
The mysterious substance that binds galaxies together could naturally be ‘in tune’ with a hidden fifth dimension, according to a new University of Sheffield theory aiming to shed light on one of science’s biggest enigmas: dark matter.
Dark Matter has been explored by scientists and science fiction writers for decades, inspiring everything from planet-destroying vortexes in Star Trek to the ‘Dust’ that sustains the multiverse in Philip Pullman’s His Dark Materials fantasy trilogy.
Yet it remains one of the greatest open problems in physics. While scientists are certain it exists due to its immense gravitational effect - acting as an invisible ‘cosmic glue’ holding galaxies together - it has never been observed and its true nature remains a mystery.
While the possibility that dark matter exists in an extra, hidden dimension has been extensively researched in recent years, scientists at the University of Sheffield have now taken that concept a step further. A new study, published in the Physical Review D journal, proposes a compelling framework to explain how dark matter behaves and why it remains so difficult to detect
The study proposes that dark matter resides in a hidden extra dimension alongside a force-carrying particle known as a dark photon. According to the theory, the specific geometry and shape of this extra dimension causes the masses of these particles to line up in a precise arrangement.
This alignment creates a phenomenon known as a dark matter resonance, which is loosely similar to how a musical instrument vibrates intensely when it hits the exact right note.
Dr Yu-Dai Tsai, a Royal Society Dorothy Hodgkin Senior Research Fellow at the University of Sheffield, said: “Dark matter resonance is already known to be a powerful idea, with the potential to change our understanding of how dark matter was produced in the early universe and how we search for it today.
“But many previous resonant dark matter models have treated the resonance as an assumption. This work gives a possible deeper origin for it: the resonance may come directly from the geometry of hidden dimensions.
"This resonance can make dark matter interactions much stronger at crucial epochs in cosmic history, such as in the early Universe. Crucially, the model allows for these strong interactions in the past while still explaining why dark matter appears so inert and hard to detect today."
While resonant dark matter and extra dimensions have both been studied independently in the past, previous models required particle masses to be meticulously tuned or ‘arranged by hand’ to make the physics work.
The Sheffield study proposes that this perfect tuning is not a coincidence, but arises naturally from the mathematical structure of the hidden dimension itself.
“Understanding dark matter would represent a profound advance in humanity’s knowledge of the cosmos and what it is made of,” Yu-Dai added.
“Our research gives physicists clear new targets in the search for dark matter, while connecting two of the biggest ideas in fundamental physics: the mystery of dark matter and the existence of hidden dimensions.”
Beyond expanding our understanding of the cosmos, the search for dark matter indirectly drives practical technological advances. The ultra-sensitive detectors, cryogenics, low-noise electronics and quantum measurement technologies developed to hunt for dark matter can power breakthroughs in medicine, computing and global communications.
