Dark matter is one of the most intriguing theories in astronomy. An invisible force that holds galaxies together so they don’t travel across the universe. It seems hard to believe, but in the universe, many things are difficult to understand, and some of the things that don’t have an explanation could remain that way, as scientists can’t travel the cosmos to get their hands dirty and put their theories to the test, everything that is confirmed or just makes sense. The theory was created by the Swiss astronomer Franz Zwicky at the University of California in 1933.
How the theory was born
Franz Zwicky observed during a study that galaxies in the Coma cluster were moving faster than could be accounted for by the visible matter, which suggested the presence of invisible matter responsible for the observed action. Later, in 1970, another astronomer, Vera Rubin, studied the galaxies’ rotation based on the dark matter theory, which led to further discoveries.
Vera Rubin’s research looked at how stars move around in spiral galaxies. What she found was surprising: the stars on the edges were moving much faster than expected. That didn’t make sense based on the visible matter alone — something else had to be pulling on them. Her observations supported an earlier idea from Fritz Zwicky and gave even more weight to the concept.
Dark matter found in a new format
Scientists now believe that dark matter — the invisible substance making up around 22% of the universe — might have formed right after the Big Bang. Their idea? Their idea is that high-energy, massless particles suddenly lost energy and gained mass, turning into what we now call dark matter. The study was published in Physical Review Letters.
According to the model, just after the Big Bang, space was filled with streams of fast-moving, photon-like particles. They were flying around at the speed of light, but something changed — a kind of magnetic-like force made them pair up. When that happened, they suddenly dropped in energy, like steam cooling off and freezing into ice.
Physicists Guanming Liang and Robert Caldwell describe the early universe as a place full of massless particles racing around at light speed — more like bursts of energy than the heavy, invisible matter we associate with dark matter today.
Similarities to other electrons
It’s similar to what happens in superconductors, where electrons form pairs (called “Cooper pairs”) and move around with no resistance. That comparison actually inspired this theory — if electrons can shift states like that, maybe dark matter particles did too.
Scientists think this energy shift left a fingerprint in the cosmic microwave background — the leftover glow from the Big Bang. And now, with today’s observatories, we might finally be able to spot that fingerprint. Guanming Liang, the lead author of the study, points out that their model doesn’t introduce new physics but builds on well-established concepts, making it straightforward to test.
Dark energy implications of future research
The next step involves analyzing data from the cosmic microwave background. If this theory holds up, it could mark a major breakthrough in how we understand the universe’s evolution. According to Caldwell, this brings us closer to solving one of modern physics’s biggest mysteries.
The dark energy could also be at stake here, as both forces would work simultaneously, almost acting like rivals. While the matter is working as a strong gravitational field holding many things together, the energy that is expanding the universe is also trying to separate the cosmic objects, leading them to new horizons. We can’t actually see the universe expanding because the light there hasn’t made its way to Earth yet, and this should take a couple of million years, from a space perspective.