London:
For someone who helped unleash the first great scientific discovery of the 21st century, Britain's Peter Higgs is a remarkably low-tech man.
The newly-minted co-laureate of the 2013 Nobel Prize for Physics has no mobile phone, no television and no Internet access in his modest flat.
Yet it is the name of this shy and unassuming 84-year-old that will be carried down the ages.
For generations to come, it will be mentioned in textbooks and honoured in scientific eulogies alongside heroes of physics such as Albert Einstein and Max Planck.
Ground-breaking theoretical work that helped explain how the Universe has mass earned Higgs and Belgian physicist Francois Englert this year's Nobel.
The accolade comes almost half a century after Higgs had his "eureka" moment, realising as a young lecturer in Edinburgh there could be a field of novel particles that confers mass.
Without the "Higgs," say theorists, we and all the other connected atoms in the Universe would not exist.
Born in Newcastle upon Tyne, in northeastern England, Higgs holds a PhD from King's College in London.
He lives quietly in the Scottish capital, where he is emeritus professor of theoretical physics, and is said to cringe every time his discovery is referred to as the "Higgs" boson, studiously avoiding the term himself.
As an atheist, he becomes even more agitated when the boson is dubbed the "God particle".
"He is a very mild-mannered and very gentle man, but he actually does get a little tenacious if you say something wrong that (has to do with) physics," Alan Walker, a fellow physicist at Edinburgh and a close friend of Higgs, has said.
The Sunday Times newspaper reported that Higgs had been in a "fragile state" this week, having fallen outside his apartment a week ago and had decided to go away for a few days to avoid all the publicity.
Recognition for Higgs and Englert came in July 2012 when the European Organisation for Nuclear Research (CERN) in Geneva said it had found a subatomic particle "consistent" with the long-sought boson.
"It's very nice to be right sometimes," Higgs said that day. "It has certainly been a long wait."
By Higgs' side, in tears, sat Englert, who with fellow Belgian Robert Brout -- who died in 2011 -- challenged convention with radical ideas about how mass is conferred.
Englert, a bearded, bespectacled and snappily-dressed 80-year-old, is emeritus professor at the Free University of Brussels (ULB).
He and Brout set down the conceptual ground work for Higgs and others to build on. The pair proposed that the newborn Universe was at first filled with massless particles but was then pervaded by a field of particles which endowed them with mass.
In an interview posted on the university's website, Englert said that he and Brout became interested in cosmology "in order to avoid being pigeon-holed by specialisation".
"It's not necessary to have read everything about a particular subject in order to get interested in it. The main thing is to sort out what's important and what is peripheral in order to be able to dive in."
Englert recalled the excitement he felt in 1964 as Brout and he put their theory together.
"We suddenly understood that our theory was flawless, from the viewpoint of logic."
Higgs and Englert have won a slew of honours. They co-won the 2004 Wolf Prize, another top physics award, and Englert was named a baron by Belgium's King Albert II in July.