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Nuno Loureiro grew up in the small town of Viseu, in central Portugal. He knew that he wanted to be a scientist, even at the beginning of elementary school, while "everyone wanted to be a policeman or firefighter," he recalls.
Her mother, now retired, taught Portuguese and French at the local high school and her father was a lawyer. But by the time Loureiro finished high school, his interest in science had crystallized and "I realized that physics was what I liked most," he said. During his undergraduate studies at the Technical University of Lisbon, he began to be interested in the merger, which "seemed to be a very attractive field", where major developments were likely over the course of the year. his life, he said.
Fusion, and more specifically plasma physics, has remained its main research center since graduate studies, postdoctoral fellowships, and now in research and teaching at MIT. He explains that plasma research "lives in two different worlds". On the one hand, it involves astrophysics, which deals with the processes that occur in and around the stars. on the other, it is part of the quest for clean, virtually inexhaustible electricity through fusion reactors.
Plasma is a kind of fourth phase of matter, similar to a gas but with the atoms separated into a kind of soup of electrons and atomic nuclei. It forms about 99% of the matter in the universe, including stars and scattered tendrils of matter spread among them. One of the most difficult challenges to understand to understand the behavior of plasmas is their turbulence, which can dissipate the energy of a reactor and which takes place in a very complex and difficult to predict – a major obstacle up to now at fusion energy.
Everyone knows the turbulence in the fluids, breaking waves in the cream brewed in the coffee, but the plasma turbulence can be very different, explains Loureiro, because the plasmas are riddled with magnetic and electric fields which push them and draw them of dynamic way. "The solar wind is a very remarkable example," he says, a stream of particles ejected by the sun and highly variable, continually highly variable, sweeping the Earth, sometimes producing auroras and affecting the communications satellites' electronics . Predicting the dynamics of such flows is a major goal of plasma research.
"The solar wind is our best plasma turbulence experiment," says Loureiro. "It's more and more well diagnosed because we have these satellites up there. This gives us relatively good access to the test. On the other hand, the study of turbulence in plasma clouds in the interstellar medium, far removed from the stars, does not include the luxury of direct sampling and must rely on observations and calculations more indirect. "There is no diagnosis, apart from astronomy observation," he says.
Loureiro began concentrating on plasma physics at Imperial College London and continued his work as a postdoctoral fellow at the Princeton Plasma Physics Laboratory and then at the Culham Center for Fusion Energy, the country's national fusion laboratory. United Kingdom. After a few years as a senior researcher at the University of Portugal, he joined the faculty of MIT Plasma Science and Fusion Center in 2015, where he held the position of titular last year. A major motivation for moving from being a researcher at MIT was working with students. "I like to teach," he says.
Loureiro and his wife Ines, who work in logistics for museum art exhibitions, including the Institute of Contemporary Art and the MIT List Gallery, have three daughters aged 12, 9 and 4 years old.
His work at MIT focused on a very specific area of plasma behavior called magnetic reconnection. An example of this process occurs in the solar corona, an irregular glowing ring that surrounds the solar disk and becomes visible from the Earth during solar eclipses. Large loops of solar material are ejected from the surface, driven in swirls of magnetic fields. Sometimes these magnetic fields become unstable and collapse, triggering a surge of energy in the form of a solar flare. "It's magnetic reconnection in action," he says.
Last year, Loureiro published with the physicist Stanislav Boldyrev, at the University of Wisconsin, several papers in which he proposed a new model to reconcile significant disparities between plasma turbulence models and tumor models. magnetic reconnection. Until now, he says, with this new model, "the type of things that we are predicting here actually corresponds to observations." However, some of its aspects may require new technologies in observation.
But the new concept, it is proven, shows that magnetic reconnection must play a crucial role in the dynamics of plasma turbulence, at all scales, which, according to Loureiro and Boldyrev, would change the understanding of dynamics. and properties of space and astrophysics. plasmas.
According to Loureiro, a real understanding of the turbulence in plasmas is essential to solve various thorny problems of physics, from the way the solar corona heats up to the structure of interstellar clouds to the dynamics of disks around black holes. And he then disconnects, using the available tools, to continue to understand the complexities of plasma behavior.
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