Asymptotic Freedom

I really love that term, though I just barely, maybe understand what it means.

Eric Drexler (he of Engines of Creation, the breakout 1987 book on nanotech) thinks the source is very cool indeed. Here from November 7:

…the most exciting paper I’ve seen on quantum field theory and gravitation in a long time. It offers no speculations about strings, extra dimensions, new symmetries, or the like, and no loop quantum gravity or causal dynamical triangulations, just a carefully cross-checked mathematical analysis that reveals how general relativity transforms quantum electrodynamics at very edge of the breakdown of GR [general relativity] itself.

The question is the strength of electric interactions — the effective magnitude of a single charge — and how it changes (as it does) at high energies and small distances.

In brief, QED predicts that the strength approaches infinity;
QED + GR predicts that the strength approaches zero.

Many of the (meager) news reports to date describe Toms’ paper as if it merely smoothed out some difficulties with calculations in QED — those pesky infinities! — but that misses the point: This result extracts new physics from old physics, sharply revising our understanding of current physical theory as it approaches the Planck scale, the very edge of the unknown.

Here it is:

Quantum gravitational contributions to quantum electrodynamics
Quantum electrodynamics describes the interactions of electrons and photons. Electric charge (the gauge coupling constant) is energy dependent, and there is a previous claim that charge is affected by gravity (described by general relativity) with the implication that the charge is reduced at high energies. However, that claim has been very controversial and the matter has not been settled. Here I report an analysis (free from the earlier controversies) demonstrating that quantum gravity corrections to quantum electrodynamics have a quadratic energy dependence that result in the electric charge vanishing at high energies, a result known as asymptotic freedom.


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