In search of the dark photon. Is there a fifth fundamental interaction?
At the National Institute of Nuclear Physics near Rome, scientists are preparing for an experiment that could answer one of the fundamental questions about the nature of reality. Is there a fifth, previously unknown fundamental interaction? We currently know of four such interactions: gravitational, electromagnetic, strong and weak. A hypothetical fifth kind could be what connects visible matter to dark matter, and finding such a connecting particle – a dark photon – would be a breakthrough in physics.
Little is known about dark matter – only that it accounts for most of the mass of the Universe. Matter, whichor we are able to observe – from stars and galaxies to humans and animals – is only 5 percent of the. its mass. Dark matter we can’t detect directly, but we can see its gravitational interaction.
Just as photons carry electromagnetic interactions, dark photons would carry the fifth fundamental interaction and affect dark matter. However, unlike photonsoHowever, unlike photons, dark photons would have a mass of. Knowledge of the mass and types of particles on which theore can disintegrate a dark photon, would provide the first glimpse of what makes up most of the Universe, ktory is beyond our perception.
The hunt for the dark photon will begin this month at Italy’s National Institute of Nuclear Physics. There is an instrument called PADME (Positron Annihilation into Dark Matter Experiment), ktory is designed to capture the hidden fifth force. The plan is to bombard a thin diamond plate with a beam of particles called positrons, ktore are antimaterial versions of electronsow.
Under normal conditions, positrons and electrons annihilate each other, forming a pair of regular photonsow. But if there really are dark photons, then once in a while, positron-electron annihilation should produce them. Then, instead of dwoch photonoin would appear dark photon and regular photon. And this is what the Italian researchers want to test.
That’s the thing about dark matter, we can’t see it. Also, there is no expectation that researchers will suddenly see a dark photon. PADME will not be able to detect it directly, but instead the missing photon will serve as a proof of theod. It would be, by the way, a proofod not only the existence of the dark photon, but also the fifth fundamental interaction.
– At the moment, we do not know what most of the Universe is composed of. If we find the fifth force, it will completely change the existing paradigm of. It would open the door to a new world and help us understand the particles and forces thatore make up dark matter and dark energy – said Mauro Raggi of Sapienza University in Rome, whoory together with cooThe researchers will take part in the planned experiment.
The experiment is expected to last at least until the end of the year. There are, however, preliminary plans to later move the PADME instrument to the laboat Cornell University, where it would be connected to a more powerful particle gas pedal than the one in Italy. It could expand the search for dark photonsow.
But it is not only in Italy that they are looking for a dark photon. Bryan McKinnon of the University of Glasgow, is involved in the search for a dark photon in the im gas pedal. Thomas Jefferson in Virginia. – The dark photon, if it exists, will allow us to look into the dark sector to see what is going on. It would certainly be a big thing in physics – McKinnon said.
What are the chances that physicists will find dowod on the existence of a fifth force in the Universe? – We are looking a bit in the dark, but if we are looking, at least we have some chance – Raggi said.
If the existence of a dark photon and a possible fifth interaction can be confirmed, it will change our perception of the Universe. It will be necessary to rewrite physics textbooks.