Anil Ananthaswamy - ... It turns out that the electric charge of fundamental particles could have been close to zero when the universe was fractions of a second old. It's all because of the action of gravity - a discovery that, if confirmed, could help pave the way for a unified description of physical reality.
The standard model of particle physics does a great job of accounting for the fundamental particles of nature and three of the forces that act upon them - the weak and strong nuclear forces, and the electromagnetic force. Unfortunately, no one knows how to fit gravity into the model.
In 2004, Frank Wilczek, David Gross and David Politzer won the physics Nobel prize for showing that particles which are acted upon by the strong force will feel it weaken as they get very close together. In quantum mechanics, small distances are associated with high energies as only energetic photons of very short wavelengths can probe down to these scales. This means that at the very large energies that existed in the early universe, the strong force would have been much less significant than now. The result helped show that the strengths of the strong, weak and electromagnetic forces were very nearly the same in the early universe, even though today the strong force is far more powerful than the other two.
... In the presence of gravity, electric charge - a barometer of the strength of the electromagnetic force - tends to go to zero as energies rise (Nature, DOI: 10.1038/nature09506). "With no gravity, the electric charge gets bigger [with higher energies]," says Toms. "Gravity changes the picture." ...via Why the early universe was free of charge - space - 04 November 2010 - New Scientist.
Related:
Ever since Galileo first dropped his balls off the top of the Tower of Pisa in the late 16th century, gravity has caused a major headache for mathematicians and physicists down the ages.
Throwing theorists' equations into chaos, it has proved a major stumbling block to the creation of a single 'theory of everything'.
But a new analysis by Dr David Toms, a theoretical physicist at Newcastle University, now shows that gravity may at least make some fundamental calculations more manageable.
He has found that gravity seems to calm the electromagnetic force at high energies. The finding could make some calculations easier, and is a rare case in which gravity seems to work in harmony with quantum mechanics, the theory of small particles. His full paper is published today in Nature.
Dr Toms explains: "The basic idea is that the value of the electric charge depends on how close you are to that charge.
"The number for the electric charge that you look up in the back of a textbook assumes that you are a very large distance - on the atomic scale - from the charge. The reason that the value changes with energy has to do with quantum mechanics.
"My research shows conclusively that charge is affected by gravity, and that it tends to make the charge weaker as you proceed to smaller distances. This is unexpected because in the complete absence of gravity the charge gets larger as the distance decreases."
In Dr Toms work, gravity seems to smoothe the interaction, making the force between the electron and photon nearly zero at high energies. This weakening of the force means that theorists can calculate the behaviour of high-energy electrons and photons after all. ...
via Physorg
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