Particle Physics Right Away Belly Up

Particle physics. Artist’s impression.

Professor Ben Allanach is a particle physicist at Cambridge University. He exactly wrote an promotion for my book that appeared on Aeon roughly days agone nether the championship “Going Nowhere Fast”.

I’m kidding of course, Allanach’s essay has no relation to my book. At to the lowest degree non that I know of. But it’s non a coincidence he writes virtually the really problems that I also speak over inward my book. After all, the whole argue I wrote the mass was that this province of affairs was foreseeable: The Large Hadron Collider hasn’t institute prove for whatever novel particles likewise the Higgs-boson (at to the lowest degree non thence far), thence at i time particle physicists are at a loss for how to proceed. Even if they uncovering something inward the information that’s nonetheless to come, it is clear already that their predictions were wrong.

Theory-development inward particle physics for the terminal forty years has worked generally past times what is known every bit “top-down” approaches. In these approaches yous invent a novel theory based on principles yous cherish too thence derive what yous aspect to run across at particle colliders. This approach has worked badly, to nation the least. The principal problem, every bit I lay out inward my book, is that the principles which physicists used to build their theories are but aesthetic requirements. Top-down approaches, for example, involve that the telephone substitution forces are unified or that the universe has additional symmetries or that the parameters inward the theory are “natural.” But none of these assumptions are necessary, they’re exactly pretty guesses.

The contrary to a top-down approach, every bit Allanach lays out, is a “bottom-up” approach. For that yous get down amongst the theories yous receive got confirmed already too add together possible modifications. You produce this thence that the modifications exclusively pop off relevant inward situations that yous receive got non nonetheless tested. Then yous aspect at the information to uncovering out which modifications are promising because they amend the represent to the data. It’s an exceedingly unpopular approach because the information receive got exactly told us over too over too over over again that the electrical flow theories are working fine too require no modification. Also, bottom-up approaches aren’t pretty which doesn’t assistance their popularity.

Allanach, every bit several other people who I know, has stopped working on supersymmetry, an stance that has for a long fourth dimension been the most pop top-down approach. In regulation it’s a proficient evolution that researchers inward the champaign force consequences from the data. But if they don’t elbow grease to empathize exactly what went incorrect – why thence many theoretical physicists believed inward ideas that produce non depict reality – they opportunity repeating the same mistake. It’s of no role if they exactly substitution i touchstone of beauty amongst another.

Bottom-up approaches are safely on the scientific side. But they also growth the opportunity that nosotros larn stuck amongst the evolution of novel theories because without top-down approaches nosotros produce non know where to aspect for novel data. That’s why I fighting inward my mass that roughly mathematical principles for theory-development are okay to use, namely those which forestall internal contradictions. I know this sounds lame too rather obvious, but inward fact it is an extremely potent requirement that, I believe, hasn’t been pushed every bit far every bit nosotros could force it.

This top-down versus bottom-up news isn’t new. It has come upwards up each fourth dimension the supposed predictions for novel particles turned out to endure wrong. And each fourth dimension the theorists inward the field, rather than recognizing the error inward their ways, but adjusted their models to evade experimental bounds too continued every bit before. Will yous permit them larn away amongst this i time again?