Research at UAEU is delving into a puzzle that lies at the core of physics – by aiming to create new knowledge about neutrinos, delve into the subject of dark matter, and unlock more of the secrets of the universe.
One of the most abundant particles in the universe, neutrinos – which are sub-atomic, extremely small light, and have no electric charge – have captured the imagination of scientists around the world for decades. Meanwhile, dark matter consists of stable, neutral particles that comprise about 90 percent of the universe’s matter.
Understanding the nature of neutrinos and dark matter is a challenge that has captivated scientists around the world for decades, and now Dr Salah Nasri, of the Department of Physics at UAEU’s College of Science, is focusing on a research project designed to produce explanations and answers.
With his primary interest being the “interplay” between particle physics and cosmology, Dr Nasri, working with a team of UAEU students, says the research is showing that while neutrinos and dark matter may appear different, there is a connection between them. “About 100 trillion neutrinos go through our body every single second, but don’t do any harm, and without these particles the sun would not shine, there would be no energy, and our elements would not be possible,” he explained.
“Understanding the nature of neutrinos, and why their mass is so small, is a problem people have been trying to understand since the 1960s. In fact, their size is crucial – if they had a different mass, the universe as we know it would be completely different.
“The other, long-standing problem my research is studying is concerned with astrophysics and cosmology, which is where dark matter comes in. We cannot see it, but we can infer its existence, because had there been no dark matter in the early existence of the universe, there would no galaxies; no stars; no planets; and no life. Understanding dark matter is one of the deepest problems in physics and has important implications in understanding our universe. So, with my team, we are looking to develop a model that can unify both neutrinos and dark matter.”
The research team found that dark matter is actually a “heavier” version of ordinary neutrinos – with a mass about 100 times that of a proton – and that this can have implications for high-energy processes such as the lepton flavor violation and the origins of the asymmetry between matter and antimatter in the universe. To conduct their project, they searched for signals of dark matter particles produced by some of the world’s foremost colliders – including the famous Large Hadron Collider at CERN in Geneva.
“We expect to see signals of signatures for dark matter and for neutrinos, and where they may collide over the next five to 10 years, making predictions based on our models,” explained Dr Nasri, whose work on this subject has led to publications in some of the world’s top scientific journals, and who last year was awarded UAEU’s College of Science Excellence Award in Scholarship.
“Our prediction was that we should see a very high level of missing energy, and that the only way to explain the 27 percent that cannot be accounted for is if dark matter is present. We also demonstrated the shape of the signals we found, because, for example, with protons, the shape is dependent on whether or not they are producing dark matter.”
Dr Nasri’s work has led to him being a plenary speaker at major international conferences and workshops, and taking a place on the editorial board of several international physics journals. He has been invited to leading research institutions such as CERN and the International Center for Theoretical Physics in Italy, and was an honorary participant at the Arab American Conference on Frontiers in Science, Engineering, and Medicine in 2016.
Meanwhile, the professional lecture notes he has compiled on topics related to physics, astrophysics, and math are used to disseminate his knowledge to undergraduate and graduate students, as well as researchers whose work concerns particle physics.