Portuguese plasma physicist and fusion energy pioneer. He died from gunshot wounds on December 16th 2025, aged 47, at his condominium in Brookline, Massachusetts.
Loureiro grew up in Viseu, a small city in the centre of Portugal. His mother was a French teacher and his father a prosecutor in the city court. He decided early that he wanted to be a scientist, though he had never met one until the age of 17. He studied at the Instituto Superior Técnico (IST) in Lisbon from 1995 to 2000, where he did well but was not top of his class. He then earned his doctorate at Imperial College London, where his thesis discussed "tearing modes" in plasma and "magnetic reconnection".
Loureiro moved to MIT in 2016 and became a full professor by 2021. By 2024 he was in charge of the Plasma Science and Fusion Centre, comprising 23,000 square metres of lab space in seven buildings with 250 researchers, staff and students.
His life's work centred on plasma, the fourth phase of matter in which ions and electrons form a super-hot broth that makes up 99.9% of the visible universe. He studied plasma turbulence, magnetic reconnection and the kinetic energy behaviour of plasma in tokamaks, comparing temperatures at the periphery and the core and constructing numerical models to predict plasma behaviour. He devised a fluid-kinetic code for plasma dynamics called Viriato, named after a Lusitanian warrior of the second century BC from his hometown of Viseu.
He received the Presidential Early Career Award for young scientists, presented by Joe Biden.
On December 13th 2025 a former IST classmate, Cláudio Manuel Neves Valente, killed two people and injured nine in the Boston area. Valente had been top of his class at IST with an average of 19/20, had gone on to Brown University but dropped out after a few months and disappeared. On December 15th he found Loureiro's condominium in Brookline and shot him. Valente later killed himself in another state. No firm motive was established, though professional jealousy seemed plausible.
Soap and education are not as sudden as a massacre, but they are more deadly in the long run.