Dark Matter: European Initiative Detects Unprecedented Signal!

This is precisely what Madmax does. Its principle is based on a dielectric haloscope, a structure composed of sapphire discs – an insulating, pure and ideal material for high frequencies – carefully aligned in front of a mirror. The idea is as follows: if a dark photon crosses this set, it could convert into visible photon at certain very specific frequencies. A bit like a radio signal that we only hear if you are perfectly wedged on the right station.

These potentially converted photons are then captured by an ultra-sensitive antenna, capable of detecting the slightest excess of energy. During the first tests, the Madmax team sought to intercept a signal around 20 GHz, a frequency corresponding to a specific theoretical mass of the dark photon. The result: no direct detection, but a major scientific breakthrough. Experience has made it possible to exclude the existence of dark photons in this range of mass with unequaled precision, much higher than the limits reached so far. And that changes the situation.

A technological breakthrough above all

What this first campaign demonstrates is not the detection of dark matter, but the validity of the method. For the first time, an experience of this type has been carried out, with a functional, stable and efficient prototype. Scientists have succeeded in maintaining a delicate configuration, capturing a signal without significant parasitic noise, and validating the entire experimental concept. Clearly: Madmax works.

This success opens the way to ambitious improvements. The next version of the experience will integrate cryogenic cooling at 4 kelvins (-269 ° C). At this temperature, thermal noise becomes negligible, which considerably increases the sensitivity of the detector. The team also plans to apply an intense magnetic field there, which will not only track down dark photons, but also to detect axions – thanks to a phenomenon called Primakoff effect, in which an axion can be transformed into a photon in a magnetic field.

In other words, Madmax only laid the foundations. His next generation may well be the one who, for the first time in history, will capture a direct signal of black matter. An advance that would upset our understanding of the cosmos.

Towards a cosmological revolution?

It must be understood that dark matter is not a simple theoretical curiosity. It is at the heart of all modern cosmology. Without it, the galaxies would not form as we observe them. The universe, on a large scale, would not have the structure that telescopes reveal. Even stars training would have followed a completely different scenario. But as long as this matter remains invisible, all these theories are based on an incomplete basis.

If Madmax – or another similar experience – one day manages to detect a real particle of dark matter, it will not only be a discovery of physics: it will be a scientific turning point. This will mean that it is finally possible to map the 85 % of the universe that has always escaped us. That day, astronomy will no longer be only the study of light, but also that of the invisible. And particle physics will enter a new era.

The most fascinating? That day could be much closer than you think. Thanks to Madmax, dark matter is no longer just a distant hypothesis. It becomes an experimental target. A target that we start, finally, to approach.

Source: Physical Review Letters