Thursday, September 12, 2019

The end of the particles

I bought Carroll's The Particle at the End of the Universe for my dad in 2013, soon after the book came out, which was soon after they finally found the "Higgs Boson". Here's Woit on it. And now, since my dad has palmed this book back to me... I'm on it too.

I'll tell y'all up front that my A-Level in Physics was a "B". I did not do more science in college; just the maths. When I was doing A-Level I recall the course being solidly Newtonian with some standard electronics thrown in. We weren't building atomic bombs in the lab. So approach this post as if it was done by an ignorant blogger just looking in on things from outside.

As I see it, the Higgs is indeed the end of the universe ... for physicists. There was a Standard Model hammered out pretty-much the year I was born. Everything done since then has affirmed that model: the W and Z particles exist, the Top Quark exists, and they all have inertial masses in accordance with the existence of a then-hypothetical field which Higgs - among others - had hypothesised.

Field theory, even for Higgs which was special, works at the quantum level as a couple of "fermions" passing massless particles around which we call "bosons". Electromagnetism, for instance, has a boson: the light-particle, "photon". The weak force has W and Z. These nonHiggs bosons have a directional impact, given that they represent interactions between fermions, so their forces work as vector fields. The Higgs field was supposed to be scalar so would work even if the fermion was sitting by itself. Mass is inertial, remember.

At least, so I've gathered.

It happens that many bosons are yuuge. The photon is obviously tiny, but the W and Z - for a start - don't last long in physical form. Under normal circumstances they only zip in and out in quantum timescales. The biggest they is, the shorter they live. We can create some bosons with enough energy but we don't see them. We can, however, see how they decay and measure the sorts of particles they give off.

All the experimenters had to do, to prove the Higgs field theory of inertial mass, was to conjure up a Higgs boson and watch how it decays. And that, they did.

But they'd pretty much gathered that this was going to happen anyway due to (for instance) the predictions of the top quark mass based on Higgs' theory.

That has been my life, watching physics experiments at this scale: seeing physicists "shoot the wounded". They looked for a Higgs boson and found it. They wondered why the mu-lepton-hydrogen method predicted a proton mass different from the mass which earlier physicists had measured by the less-precise election method; they figured that out (the less-precise method had barfed out the wrong number). Black holes were surmised to have no stranded extra properties beyond mass, spin, and serialnumber charge; ayep.

I'm not going to call the end of Standard Model physics but I am going to say that we are at Diminishing Returns. I got convinced we'd reached that point in the early 1990s - and so did the voters (I was not yet an American voter) - which is why Congress called off the Nacogdoches Super Collider (yee haw!). Experimental physics was better placed in gravitational inferometers like LIGO, looking at the great particle-colliders that are neutron-star collisions.

UPDATES 9/16 - Carroll has entered Woit's killfile. Also, as usually happens, Turtle Island has a parallel post that's better than mine.

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