Three American scientists won the 2004 Nobel physics prize on Tuesday for showing how tiny quark particles interact, helping to explain everything from how a coin spins to how the universe was built.
David Gross, David Politzer and Frank Wilczek showed how the attraction between quarks - nature's basic building blocks - is strong when they are far apart and weak when they are close together, like the tension in an elastic band when it is pulled.
The Royal Swedish Academy of Sciences said their work helped give "a unified description of all the forces of Nature ... from the tiniest distances within the atomic nucleus to the vast distances of the universe".
It explained how "an everyday phenomenon like a coin spinning on a table" is determined by fundamental forces.
The three scientists showed how quarks, the building blocks of protons and neutrons, were held together by a so-called "strong force".
Without this force there would be nothing holding the tiny particles together, nor indeed any basic building blocks to assemble into an object like a coin.
"They really helped us to understand how it is that quarks are bound together to make protons and neutrons," said David Wark, a particle physicist at the Rutherford Appleton Laboratories in Britain.
Their theory, known as quantum chromodynamics, also showed that when quarks are close together at extremely high energies they act like free particles, a state they called "asymptotic freedom".
In this state, they resembled those of the other forces in subatomic physics - electromagnetism and the "weak force" dealing with nuclear decay - meaning the US trio had made a first step to "the theory of everything," Gross told Reuters by phone from Santa Barbara, California.
A grand unified theory of the universe has eluded scientists, who cannot yet reconcile the way subatomic particles behave with theories on the force of gravity.
"Once you understand all these forces it turns out that there are certain features that cry out for unification," Gross added. "Remarkably at the same energy almost, gravity also becomes equally strong."
The next stage of unification involves "not just these forces that govern atoms and nuclear behaviour "but also all the universe," Gross said. "That's one of the main goals and efforts of the last 20 years to search for the unified theory."
Wilczek, speaking in Cambridge, Massachusetts, said the trio's theories first appeared "outlandish" when they emerged in the 1970s and Nobel recognition came as a "great relief".
Finnish theoretical physicist Stig-Erik Starck said the trio's research had "built a model of how the universe was born, how it works and how it will ultimately die".
Gross from the University of California, Politzer from the California Institute of Technology and Wilczek at the Massachusetts Institute of Technology will share the 10 million crown ($1.36 million) prize.
"I have no idea what to do with the money, my wife has some ideas," said Gross. "We don't have champage on ice but its probably a good idea."