Stringy Ectoplasm

It is a commonplace for folks to imagine that lasting innovation in physics is down to raw intelligence. I think it may be more complicated than that. Physics is most definitely not mathematics. Pure intelligence is an unqualified asset in mathematics, but, in physics this seems doubtful. After all:

It is about Nature, Not about You.

A good example is Richard P. Feynman. Undoubtedly a great genius, Feynman was not your regular smart guy. A most appealing attribute of this “half-genius half-buffoon” was his proud reflection of a moderate IQ, 127 he claimed. However, you never know with Feynman. Ever the showman, he also aced the USA Putnam math exams.

This leads me to reflect on the high profile of String Theorists. I find this puzzling given the tenuous links to observational data. String theory is everywhere in the Mind and appears nowhere in Nature. How did these folks hoodwink everybody?

It is hard to puncture this eternally inflating bubble of irrelevance. String theorists seem impervious to criticism. If you were feeling cruel you might observe:

That’s some Pretty Pulchritudinous Phenomenology you’re Packing my P-Braned Pal!

However, string theorists do not get out much. They probably don’t spend much time in bars and would doubtless consider this an insult.

In short, I have to admire them for getting away with it thus far.

There has grown up around this community a popular view that they are the smartest of the smart and therefore must be on the right track. About this I have mixed feelings. I have zero doubt that Edward Witten is an order of magnitude more intelligent than me. However, I have grave doubts that string theory is on the right track in physics.

The reason has to do with something that really was exceptional about Feynman. He knew in his bones when he was fooling himself and backed away.

It is about Nature, Not about You.

Clever may be a pleasant detour, but Right is the correct destination.

Sometimes being right means appearing to be dumb.

Let me illustrate. String theory is popular because the notion of an “extended object” seems like the “right” way to move beyond point particles. The physical reasons for wanting to do that have to do with infinities in quantum field theory.

These are especially acute for quantum gravity which happens not to fit the pattern of other theories. String theory is a neat piece of mathematics which intuitively seemed to fit the idea of how you might propose other degrees of freedom and then integrate them out to make the theory finite. People who are excellent mathematicians warm to this idea. They are drawn to it like moths to a flame: it seems “obviously right”.

However, this is where it pays to be less smart but more in tune with Nature. It may shock folks, but we actually have little evidence that particles are point-like.

The best example I know of is Carver Mead with his Collective Electrodynamics. Mead develops a cogent argument that we have misunderstood electrodynamics. He points out that coherent quantum behavior represents the real lesson of “how things are”.

This is important, because the popular view is that Quantum Mechanics is intrinsically indeterminate. Carver Mead provides a straightforward path of reasoning to a different conclusion. He argues, successfully I believe, that the indeterminacy is a function of a particular observational regime. Instead of supposing that we know how things are at the subatomic level, we should recognize how things are at our level.

Carver Mead may well lay claim to be operating in the tradition of Newton: Hypotheses non fingo. I make no hypothesis. I invoke what is necessary to explain the data and no more. I do not presume to know why it is that way. I make no hypothesis. The task of the Scientist is to mold his or her mind to the Ways of Nature.

Another fine example of this trend is John G. Cramer and his Transactional Quantum Mechanics. This can be best understood as a development of the Wheeler-Feynman Source–Absorber theory. The idea is to consider the “photon” and all other “exchange quanta” as resonance phenomena between the source and the absorber. The result is a transactional view of exchange quanta. This provides a different explanation of photons, and indeed all other such quanta as artifacts of resonant interaction.

I find these ideas interesting because they conform to a long tradition of conceptual physics. This approach involves deep thinking about physical models. It places at a lower rung the sophistication of the mathematics. A wonderful historical example is the dielectric model of H.A. Lorentz in his landmark: Theory of Electrons. This may have been classical, but it is still useful.

A contemporary example is Tony Seigman’s book Lasers which manages to develop most every aspect of laser operation using only classical physics.

People schooled in the finer details of Quantum Electrodynamics might find such works quaint. However, the goal of physics is to understand not to impress.

In contrast, String theory seems to come at things backwards. It proposes that more sophisticated mathematics is necessary to understand the structure of matter.

When this fails, the String Theorists claim: If theory does not work, let us invent new Hypothetical Universes where it might.

I am not a believer.