Which mechanism earned Peter Higgs and François Englert the 2013 Nobel Prize in Physics?

The Higgs mechanism earned Peter Higgs and François Englert the 2013 Nobel Prize in Physics. The Nobel Committee cited their theoretical discovery of a mechanism that contributes to understanding the origin of mass of subatomic particles.

Englert and Robert Brout, and independently Higgs, published the relevant theory in 1964. It proposed that particles interact with an all-pervading field; those interactions give certain elementary particles mass. The associated quantum excitation is the Higgs boson.

The Large Hadron Collider at CERN announced evidence for a Higgs-like particle in 2012, with experiments by ATLAS and CMS. The discovery confirmed a key prediction of the Standard Model. The Higgs mechanism does not explain all mass in the universe: much of the mass of protons and neutrons comes from strong-force energy inside them.