François Englert, Scientist Who Helped Explain How Particles Get Mass, Dies at 93

François Englert, a Belgian physicist who helped figure out why particles have mass, died on Thursday in Uccle, Belgium, near the capital city of Brussels. He was 93 years old. Englert shared the 2013 Nobel Prize in Physics with British scientist Peter Higgs for their work on what became known as the Higgs field — a theory that explained one of the biggest mysteries in science. His death was announced by CERN, the European science organization famous for its giant particle accelerator.

Englert's most important work had to do with a question that puzzled physicists for decades: why do particles have mass? Along with his close friend and fellow scientist Robert Brout, Englert came up with a bold idea in the early 1960s. They suggested that an invisible field exists everywhere in the universe, like a kind of cosmic molasses, and that particles get their mass by moving through it. This field became known as the Higgs field, and the two men published their idea in a scientific journal in August 1964.

Less than two months later, Peter Higgs published a similar idea in the same journal. Another team of scientists — Gerald Guralnik, C. Richard Hagen, and Tom Kibble — published a related paper shortly after that. Together, these papers changed the way scientists understood the universe. The theory predicted that if the Higgs field were hit with enough energy, it would create a special particle. Scientists called this particle the Higgs boson, though it was also nicknamed 'the God particle' because it was so hard to find and so important to physics.

For decades, no one had the technology to actually detect the Higgs boson. That changed on July 4, 2012, when scientists at CERN announced they had finally found it. Hundreds of researchers packed a large hall to hear the news. 'I think we have it,' said Rolf-Dieter Heuer, who was then the director general of CERN, to thunderous applause. Peter Higgs was in the audience with tears in his eyes, and Englert was sitting right beside him.

The discovery proved that the Higgs field really exists, confirming a theory that had taken nearly 50 years to test. The Higgs boson is extremely fragile — it falls apart in just one trillionth of a second after it appears. But detecting it was enough to show that the field responsible for giving all particles their mass is real. It was a huge moment for the Standard Model, which is the scientific framework that organizes all known particles and forces and is considered one of science's greatest achievements.

To understand why this discovery mattered, it helps to know a little about symmetry in physics. Symmetry describes how something can change in certain ways while still staying the same — like a ball that looks the same no matter how you rotate it. In particle physics, symmetry rules help explain how particles interact with each other. But when scientists tried to explain the weak force, which causes radioactive decay in atoms, they ran into a problem. The particles involved in the weak force, called W and Z bosons, needed to have mass — and having mass seemed to break the symmetry that the equations required.

Dr. Nambu, a Japanese American physicist, had shown mathematically that symmetry could be broken spontaneously, like a pencil balanced on its tip that eventually tips over. His work helped open the door for Englert and Brout's idea. By suggesting that a field fills all of space and gives particles their mass, they offered a way to explain where the W and Z bosons get their mass without breaking the math. This idea became known as the Brout-Englert-Higgs mechanism.

Englert's life story was not just about science. He was born on November 6, 1932, in Etterbeek, Belgium, to Polish Jewish parents who had moved to Belgium in 1924. When Nazi Germany invaded Belgium in May 1940, his family's life was turned upside down. They were forced to wear yellow stars to identify themselves as Jewish, and in 1942, when Nazis began sending Jewish people to concentration camps, the family split up to improve their chances of survival. Young François was placed with a couple who owned a café, and he did not know where his parents were for about a year.

Eventually, the family came back together and escaped in the night to a small village called Annevoie-Rouillon in the Ardennes region. A local priest took them in, introduced them as Christians, and even had François baptized so he could attend a nearby school. The immediate family survived the war, but their relatives in Poland were killed during the Holocaust. For many years, Englert said, he tried to push those painful memories away. 'After the war, to protect myself, I tended to erase from my memory this period of my existence,' he said in a 2017 interview.

After the war, Englert studied engineering and then physics at the Free University of Brussels, earning his doctorate in 1959. He went on to do research at Cornell University in the United States, where he first met Robert Brout. When he returned to Belgium in 1961, Brout followed, and the two founded a physics research group together. That partnership led to the groundbreaking 1964 paper that would eventually earn Englert a share of the Nobel Prize. Brout died in 2011, two years before the prize was awarded, so he was not able to share in the honor.

In addition to the Nobel Prize, Englert received many other honors during his lifetime. In 2004, he and Brout and Higgs received the prestigious Wolf Prize in Physics. In 2013, King Albert II of Belgium made Englert a baron. He is survived by his five children and his third wife, Mira Nikomarow. When asked what he would say to the people who sheltered his family during the war, he said he would tell them that he had managed to do something with his life — and that he owed it all to them.