Peter Higgs, whose success as a physicist depends on whom you ask

Peter Higgs poses in front of an image of a detector of the Large Hadron Collider, November 12, 2013, in London.
| Photo Credit: Toby Melville/Reuters

The day the physicist Peter Higgs passed away, April 8, Google search results were rife with headlines that the man who proposed the “God particle” was no more. Dr Higgs was famously private, having stayed away from the press for most of his career, yet while his opinions on many matters were out of view, it wasn’t a secret he didn’t want the particle named for him to be named for him alone — much less the “God particle”.

In 1964, three groups of physicists working independently all proposed the existence of an elementary particle that gave some other particles some energy, often understood as mass. (According to Albert Einstein’s mass-energy equivalence, mass is energy at rest.) This energy was required to explain some observations in experiments that didn’t fit the theories of elementary particles at the time. It was considered a very difficult problem because the solution also had to follow some rules of the theory that people had worked out by then.

The particle the groups proposed was the smallest packet of energy in an energy field pervading the whole universe. When a different elementary particle enters this field, the physicists proposed a mechanism by which their particle would interact with the newcomer and give it mass. Today, the field is called the Higgs field, the particle the Higgs boson, and the mechanism the Higgs mechanism.

Based on the recent work of some other physicists, including Yoichiro Nambu and Philip Warren Anderson, Robert Brout and François Englert published their paper in August 1964. Peter Higgs followed in October (following up from a discussion he’d had with Walter Gilbert the previous month), and Gerald Guralnik, Carl Hagen, and Tom Kibble in November. So Dr Higgs said he preferred calling it the “ABEGHHK’tH mechanism”, after all the people who contributed to its theory. (The ‘’tH’ is for Gerardus ’t Hooft.)

Also read: Explained | The decade-long search for a rare Higgs boson decay 

In a rare 2013 interview, Dr Higgs said “calling it [the] ‘Higgs boson’ means choosing from a list of numerous people involved in the investigation in 1964. Nor do I agree with the statement that this all started in 1972, when someone associated my name with some characteristics of the series or the formula, and with conferences. … I would like to point out that my role has been overstated within the scientific community.”

The “God particle” label is itself a misnomer. Dr Higgs’s peer Leon Lederman had called it the “goddamn particle” in a book because it was proving so hard to find in physics experiments. Dr Lederman’s publisher changed it to “God particle” because this was more palatable, although Dr Lederman also later used it to allude to the Book of Genesis. Nonetheless, Dr Higgs later called the label a “sham” and a “joke”.

Just predicting the particle’s existence with certain properties was a big achievement, but it soon became clear finding it would be even bigger. Physicists had found a solution to the mass problem using complex mathematics but they weren’t sure that’s how nature did it too. By the 1980s, confirming this became the “central problem” in particle physics.

It was finally solved by the world’s largest machine to date: the behemoth Large Hadron Collider at the European Organisation for Nuclear Research (CERN). Built with a $9 billion budget, the LHC was designed to energise billions of protons in two beams, smash them against each other, and look for signs of the Higgs boson (and various other particles) in the debris using a suite of giant detectors. The LHC collaboration confirmed it had finally discovered the “ABEGHHK’tH particle” in 2012. The next year, the Nobel Committee awarded its physics prize to Peter Higgs and François Englert. Robert Brout, Dr. Englert’s coauthor in 1964, had died in 2011. While the Nobel Prize is awarded to three people at a time, members of the third group were excluded.

Today, particle physicists around the world are locked in a debate over whether they need a new, bigger version of the LHC to find yet other particles they’re looking for.

For all his reclusivity — Dr Higgs didn’t own a phone — some of Dr Higgs’s views on more important topics were clear. He was critical of the U.K.’s royal titles system; declined to receive the coveted Wolf Prize in 2004 to protest Israel’s treatment of Palestinians; was involved in the Campaign for Nuclear Disarmament until it expanded its opposition to nuclear weapons to include nuclear power; and with Greenpeace until it started to campaign against genetically modified organisms.

Dr Higgs was also not a fan of the prevailing academic culture, in which scientists who don’t publish enough papers could fall behind in their careers. For many years, Dr Higgs’s paper output was zero. But he also voiced a significant flip side: “It’s difficult to imagine how I would ever have enough peace and quiet in the present sort of climate to do what I did in 1964.”

• In 1964, three groups of physicists working independently all proposed the existence of an elementary particle that gave some other particles some energy, often understood as mass
• Dr Higgs’s peer Leon Lederman had called it the “goddamn particle” in a book because it was proving so hard to find in physics experiments
• Dr Higgs was not a fan of the prevailing academic culture in which scientists who don’t publish enough papers could fall behind in their careers