A principal aim of The Trouble with Physics is to re-engagetheory with what actually occurs, or may occur, in the realm of observable phenomena. The book also addresses such core questions as: Why do quarks, leptons and gauge bosons have the diverse masses they possess? What are dark matter and dark energy? How can quantum mechanics and general relativity be combined into a single theory?
String theory originally shared most of these goals, but it got caught up in its own mathematical beauty. Like Narcissus, it increasingly began to contemplate its own reflection, to the exclusion of observable phenomena.
What kind of truth is mathematical beauty? The use of the word reminded me of what former particle physicist and current Anglican priest, Rev. Dr. John Polkinghorne suggested in an American Public Media Speaking of Faith interview (described here), where he said of the subject of math that "In fact, if you've got some ugly equations, you've almost certainly haven't got it right."
Most people will eventually find what they're seeking, whether it's beauty or completeness or economical expression or any number of other attributes we find pleasant. Belief, in that sense, is what we expect. It's what pulls us forward. Perhaps mathematical physics has gone too far afield in search of a unified physical theory - the languages deployed to map these conjectures are far, far beyond my ability and talent. If the math excludes and is in conflict with observable phenomena, then theory must, and should, accommodate empirical reality.
But it's equally true that humans are goal-seeking beings with certain expectations - beliefs - at work, some known, some not. It's the "what may occur" in the paragraph above that gives me pause, not because I don't trust science, but because science doesn't do itself.
It seems possible, even likely - here's a belief for you - that physics proper and mathematics are going their separate ways. I understand that string theory makes some physicists uncomfortable. After all, it cannot be refuted, tested, falsified or otherwise dissected. Having said that, beauty does not strike me as something that should be held up for inspection, but something, rather, to be held close. Good on the mathematicians.
Happy Valentine's Day.
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