Gravitation as Frog

A frog levitating in a 16 Tesla magnetic field. Credit: High Field Magnet Laboratory, Radboud University, Nijmegen, Netherlands

A frog levitating in a 16 Tesla magnetic field. Credit: High Field Magnet Laboratory, Radboud University, Nijmegen, Netherlands


Sep 02, 2013

A gravity-only Universe cannot explain certain discrepancies.

Ilya Prigogine, from a young age, was concerned that accepted physical theory had a couple of glaring discrepancies from observation: determinism and time symmetry. Most observations are of contingency and irreversibility. No one has yet seen an egg “un-fry” or an old woman rise from her grave and grow young.

After years of effort, Prigogine has extended the basic laws of physics to account for irreversibility by incorporating recent discoveries in complexity theory and instability physics. As he relates in The End Of Certainty, the results place probability (or, better, possibility) at the core of physical processes. The traditional formulations of mechanistic determinism become a special case for isolated systems at equilibrium.

The contrast between the isolated stable models and the interacting unstable ones is as striking as the difference between a dissected frog and its jumping counterpart. The pins of equilibrium and the scalpel of reductionism lay out the frog’s mechanism to be described in great detail. But the frog doesn’t move.

Now consider gravitation: F = GMm/R^2 is well-pinned-down. As one of Piet Hein’s grooks says: ” … and who could doubt it, if you have no doubt about it.” But when taken off the dissecting table of theory, it starts to quiver: Every measurement of the “constant” G comes up with a different value. Well, maybe someone bumped the table. But now various space probes around the solar system are showing anomalous deceleration. The frog is kicking.

When the frog jumps into the galaxy, it behaves unexpectedly: It swims. Decades of observations of velocities and positions of stars have allowed astronomers to construct a diagram of how the galaxy is rotating. Surprisingly, the stars near the edge move about as fast as the stars near the center. In fact, all the stars are moving at about the same speed. Apparently, F = GMm/R.

But not to worry: we can get the frog back on the table by catching it in a net of dark matter. Never mind that the net is more massive than the entire galaxy or that we can’t see it. The important thing is to retrieve the frog—and kill it!

Now Halton Arp’s discovery of the association of quasars with nearby galaxies combined with the discovery of the quantization of redshifts threatens to let the frog escape for good. Each cluster of galaxies and quasars has a slightly different “constant” of quantization. Within each cluster, the quantization spikes are so sharp, the dispersion so small, that when the quantization effect is removed, there is almost no redshift left to attribute to orbital velocities. Arp remarks on page 114 of Quasars, Redshifts and Controversies: “Surely gravitation is still working!” The galaxies and their associated
quasars are just hanging in space, thumbing their noses at Newton: F = 0.

The point of this—getting back to Ilya Prigogine—is that “live” systems are considerably more complex than “dead” ones. Every theory has its “domain of validity”, as Leon Rosenfeld remarked. But the boundaries of that domain are almost never surveyed. It’s easier to crank out the mathematics of a theory than to discover its limitations, and, human nature inclining as it does to the haughtiness of the gods, it’s easier to assume universal validity than to mark out the provinces.

But universality is merely an assumption standing in for the hard work of verification. Gravitation as we know it will be universal only when its relationships are actually verified throughout space and throughout history. Just as galactic rotation curves and quantized redshifts challenge the easy spatial extrapolation of the “dead” theory, so the detailed global structure of myth challenges the easy temporal extrapolation.

The frog is swimming in an uncharted ocean where myth and redshifts proclaim: HERE BE DRAGONS.

Universal Gravitation is beginning to look like a dead frog in a farm pond.

Mel Acheson

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