Tuesday, March 27, 2012

Data That Outpace Theory?

There's something very wrong with the "theme" of this NY Times article. It started with the infamous Eddington's quote.

The British astrophysicist Arthur S. Eddington once wrote, “No experiment should be believed until it has been confirmed by theory.”
In this case, the issue of neutrinos moving faster than light from the OPERA experiment was  used as the poster child to illustrate the "validity" of the quote.

Eddington’s dictum is not as radical as it might sound. He made it after early measurements of the rate of expansion of the universe made it appear that our planet was older than the cosmos in which it resides — an untenable notion. “It means that science is not just a book of facts, it is understanding as well,” explained Michael S. Turner, a cosmologist at the University of Chicago, who says the Eddington saying is one of his favorites. If a “fact” cannot be understood, fitted into a conceptual framework that we have reason to believe in, or confirmed independently some other way, it risks becoming what journalists like to call a “permanent exclusive” — wrong.
People here are confusing between a valid "fact" that comes experiment, versus something that is still being debated to be valid. The OPERA result was by NO MEANS a "fact"! The validity of the result was still debated. It doesn't qualify to be a fact!

A valid fact is a valid fact. The discovery of high-Tc superconductivity came without any theory. In fact, after more than 20 years of its discovery, there is still no valid theory for this family of material. There are, however, an abundance of FACTS, ranging from the values of Tc for many of the cuprate superconductors, to the symmetry of the order parameter, etc.. etc. Does that mean that since these things are not understood in a coherent theory, that they are "permanent exclusive"?

And let's go to the other extreme - String Theory - a theory that has outpaced data! Or in this case, a theory that has ZERO data. Is this any better?

We should also not forget that phenomena such as the blackbody spectrum, photoelectric effect, atomic spectra, etc. were ALL "facts" that came first, ahead of quantum mechanics. In fact, I would say that the majority of the expansion of our knowledge came via unexpected discovery in experiments FIRST, ahead of any existing theory to describe those phenomena. CP violation, fractional quantum hall effect, superconductivity, etc.. etc. were all knowledge that got initiated via experiments first, well ahead of a theoretical understanding.

Certainly, physics involves both theory and experimental verifications. That is not the issue. For something to be considered to be "understood", there must be both. However, for experimental facts to be valid, they do  not have to require a theory to be there. We have seen enough examples of this already.


No comments: