uncovered no sign of alpha changing over time. Their experiment was precise enough that it would have revealed a variation in alpha as little as one part per quadrillion per year; nevertheless, alpha didn’t blink. Another team, headed by Raghunathan Srianand of the Inter University Centre for Astronomy and Astrophysics in Pune, India, conducted a survey of distant quasars using the Very Large Telescope. Analyzing these quasars’ absorption spectra, the team established constraints on alpha variation at least four times stricter than those of Hänsch’s group.

Physicists and astronomers continue to examine the stony face of alpha, looking for any signs of a twitch. Probing the widest possible range of objects, from atoms to quasars, they are assessing its sturdiness (or flexibility) with ever-sharper tools. A host of contemporary physical theories await their results.

A MATTER OF SCALE

Each cosmological model rests on the bedrock of particular fundamental principles. Even if certain “constants” actually turned out to vary, other aspects of the cosmos could well transcend time’s capriciousness and remain true forever. They need not involve actual physical parameters, such as charge or mass, but might represent simple mathematical rules.

Some modern thinkers, inspired in part by mathematician Benoit Mandelbrot’s concept of fractals, have suggested that the universal guiding principle is “self-similarity.” Self-similarity, the hallmark of fractal structures, means that a portion of something, sufficiently enlarged, resembles the whole thing. Mandelbrot discovered numerous examples of self-similar geometries in nature—from the delicate patterns of snowflakes to the jagged profiles of coastlines.

Consider, for instance, the shapes of trees. Trees generally have a few main limbs extending from their trunks. From these major branches grow smaller branches; from those, tiny twigs; and so forth.



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