🇬🇧Peter
Higgs

On a July morning in 2012, Peter Higgs sat in an auditorium at CERN, the European particle physics laboratory outside Geneva, and wept. He had been thirty-five years old when he wrote down the theoretical prediction being confirmed at the podium. He was eighty-three now. The scientists presenting the data — thousands of physicists, engineers, and technicians who had spent decades building and operating the Large Hadron Collider, the most complex machine ever constructed — had detected, at last, the particle that bears his name. The Higgs boson. Higgs wiped his eyes and said, quietly, that he had not expected this to happen in his lifetime.

Peter Ware Higgs was born on May 29, 1929, in Newcastle upon Tyne, the son of a BBC sound engineer. His family moved frequently during his childhood, following his father's postings, and Higgs was largely self-taught through his early school years — partly by reading the textbooks of Paul Dirac, one of the founders of quantum mechanics, which he found in the house where his family lodged in Bristol. He excelled in mathematics and physics at Cotham Grammar School in Bristol, won a scholarship to King's College London, and completed his PhD there in 1954. After several years at various British universities, he joined the University of Edinburgh in 1960, where he would remain for the rest of his career.

The insight that produced the Higgs mechanism came in 1964, during a solitary walk in the Cairngorm mountains of Scotland. Higgs had been wrestling with a fundamental problem in particle physics: the emerging theory of the weak nuclear force required the force-carrying particles — the W and Z bosons — to have mass. But the existing mathematical framework demanded that force-carrying particles be massless. This contradiction was an obstacle to constructing a consistent theory of the weak force. Walking in the Cairngorms, Higgs worked out a solution: a quantum field that permeates all of space, with which particles interact as they move through it, acquiring mass through the interaction in proportion to how strongly they couple to the field. The heavier the particle, the more strongly it is dragged by the field. And the field itself, when excited sufficiently, would manifest as a detectable particle — the Higgs boson.

He wrote up the idea as a short paper. The paper was initially rejected by the journal Physics Letters, whose editor found it insufficiently significant for publication. Higgs added a paragraph predicting that the field would have a measurable excitation — the boson — revised the paper, and submitted it to Physical Review Letters, where it was accepted and published in October 1964. The paper was two pages long. At the same time, two independent groups — François Englert and Robert Brout in Brussels, and Gerald Guralnik, Carl Hagen, and Tom Kibble in London — published similar proposals. The mechanism became known as the Brout-Englert-Higgs mechanism. The particle was called the Higgs boson, after the man who had most explicitly predicted its observable existence.

For nearly half a century, the Higgs boson remained the one confirmed-undetected ingredient of the Standard Model of particle physics — the theoretical framework that describes all known fundamental particles and forces. The Standard Model without the Higgs was like a skeleton without cartilage; the mechanism that held everything together was missing its observable keystone. In 2008, CERN switched on the Large Hadron Collider, the $10 billion, 27-kilometre circular particle accelerator built beneath the Swiss-French border, specifically designed to have enough energy to produce a Higgs boson. On July 4, 2012, the CERN experiments ATLAS and CMS jointly announced the discovery of a new particle consistent with the Higgs boson, with a mass of approximately 125 GeV. In October 2013, the Nobel Prize in Physics was awarded to Peter Higgs and François Englert. Robert Brout had died in 2011 and was ineligible. Peter Higgs died on April 8, 2024, in Edinburgh, aged ninety-four, having spent sixty years in the city where he first wrote down the idea that gave the world its mass.