The appearance on the LRB blog of an article about the importance of the Higgs boson question has made me decide to post this here. I was recently asked by a relative:
I just thought I'd ask you how you felt about the 'discovery' of the Higgs-Boson particle. It's obviously of great importance but most people, myself included, struggle to understand why.
I replied by saying:
It all boils down to the question: why do overarching explanations about phenomena matter? For a long time, people saw lightning blots, sparks from rubbed amber rods, lodestones and lots of other things; and thought they were all unrelated - like a kind of zoo of interesting but unrelated phenomena.
When electricity and magnetism were found to be analogous expressions of a uniting, underlying "electromagnetism", then suddenly we know and can do so many more things (but I want to stress that knowing about phenomena is more important than merely turning them into engineering applications!) Electromagnetism even explains why objects are solid to the touch, even though they consist mostly of empty space: and nobody who was looking at amber rods or lodestones saw that one coming! And confirming a unifying theory is important, simply because we can only truly proceed beyond them, when we're sure they're true.
If you look at fundamental particles, the deep fundamentals that lie beneath electromagnetism, and nuclear decay, and fusion, and fission, and everything going on at that scale... everything we've discovered so far point to a predominant theory (the "Standard Model") being correct; but other theories could also be correct, including theories we don't even know about yet because we've only so many scientist-hours in the day to think about these things.
We have already found that twelve fundamental particles making up "everything" explains that zoo of apparently unrelated tracks that you get in a CERN cloud chamber; these twelve interact with each other by exchanging four other particles. When you try to put together a theory to explain these sixteen particles, a seventeenth pops out.
The seventeenth - if it exists, which yesterday's results suggest is likely - would also really convenient because it explains so much of everything else, specifically why different particles have different masses (or even how mass comes about at all.) This is the first big unintended consequence of this unifying theory, much like electromagnetism being behind "solidity."
Science is at its strongest when it makes bold claims. It's the "falsifiability" theory of science: if you claim, like Einstein did, that the universe keeps the speed of light constant and instead bends space and time to preserve this, then that's a bold claim. It's a claim that can be proved false straightforwardly - if not easily - and the experimenters can then rub their hands with glee and set to work. The proposal that a Higgs particle must exist is similarly a bold claim, and if it turns out to be true then in a sense it vindicates over fifty years of work by tens of thousands of scientists.
It's a bit like the paragraph in a Sherlock Holmes story where he sees an inconsequential clue and his eyes light up. Holmes has already seen sixteen clues, and they point to two or three explanations; but as far as he's concerned, his favourite explanation absolutely demands a seventeenth fact - a really unlikely one - to become apparent. When it does so, then everything else falls into place, and his investigations make - rather aptly - a quantum leap.
I hope this makes some sense of its importance. In the grand scheme of things, the Higgs boson is just one of the more uninteresting fundamental and composite particles that you can see evidence of - briefly, flickeringly - in places like CERN. But if there is definitely no Higgs boson, then there is no well understood "grand scheme of things" for it to sit in....
I might also add that, even if there really were no Higgs boson in the experimental data, it would scarcely undermine particle physics as a discipline. If anything, things get more exciting, the less satisfying they are; after all, the patterns in those sixteen particles we do know about all have to be explained somehow, so we have to keep trying explanations until we work it out...
