To the dismay of physics geeks everywhere, theoretical particle physics struck out at the plate this year. Three swings, three misses. (Well, maybe one wasn’t really a swing. More a taken ball the umpire called a strike.) It was a crushing disappointment for those of us hoping for a rule-change to the game.
On the other hand, cosmology geeks got three recent home runs, so there was victory (with more coming!) for those who peer at the big and distant. On the other other hand, none of those were game-changers either. (They were just, you know, awesome.)
Since I follow both physics and cosmology, win some, lose some.
This post is about the strike out, so I’ll just list the three homers, two by NASA and one by the LIGO team.
For the record:
- NASA sent New Horizons to Pluto (and beyond!)
- NASA also sent the ion-propelled Dawn to Vesta and Ceres
- LIGO detected gravity waves (predicted by Einstein)
All good stuff (great stuff!), even if none of it is a game-changer.
If NASA ever finds aliens, or even just signs of life, that will be a game-changer. Sort of.
As we expected to find the Higgs boson, we pretty much expect to find some sort of life.
Be more shocking if we don’t!
I suspect we’ll not find intelligent life, though. Maybe not complex life, or even multi-cell life, but we’ll see.
[I wrote a post last August, BB #46: We’re the Ancestors!, that suggested humanity may have arrived on the scene pretty early in the universe’s eventual full history. I’ve been seeing news stories recently about how scientists are now starting to think the same thing. Remember, you read it here first!]
That’s a huuuuge disappointment. Had the bump turned out to be a real signal, it would mean a new particle — new physics, something we’ve been seeking for about 50 years.
And, of course, we finally saw the Higgs boson (or a Higgs boson) last year. With that, the Standard Model is complete, both in theory and, at long last, observation.
But we know for sure that there’s no way both quantum physics and general relativity are complete models (let alone accurate descriptions of reality rather than just models that work). They don’t fit together, and that begs a resolution. So far, we only have ideas!
Speculative physics: Supersymmetry. Certain aspects of particle physics work better if all the fundamental particles we’ve found in the Standard Model also have supersymmetric partner particles. But so far we haven’t found any, and each new experiment closes the window a little further.
Physicists who work on supersymmetry are running out of models to test!
The second strikeout came with the announcement by researchers at LUX (Large Underground Xenon experiment) that, having completed their experiment, no dark matter particles had been found by their detector, which was the most sensitive made so far.
While this doesn’t mean the dark matter particles don’t exist, it does tighten the constraints on where they might yet exist.
As with supersymmetry, we’re starting to run out of places to look!
And, since dark matter particles aren’t part of the Standard Model, finding such a particle would also mean new physics!
This, along with LIGO spotting black holes, seems to be reviving interest in the idea of black holes, or MACHOS (MAssive Compact Halo Objects), as the source of the dark matter that’s making galaxies spin faster than they should if they were made totally of ordinary matter.
On the other hand, various cosmological observations are narrowing the window on what sizes those might be. (If they were within certain size ranges, we would have spotted them by now.)
They believe their data is sufficient to essentially rule out the existence of such a particle.
Neutrinos are weird matter particles (but part of the SM) that only interact with matter via the weak force (and gravity, of course). They have no charge and very little mass.
Sterile neutrinos are even more elusive because they don’t interact with the weak force.
Finding them would mean, you guessed it, new physics, since they aren’t really called out in the Standard Model. They’re thought to possibly be right-handed neutrinos which are potentially accounted for through observations of other right-handed fermions.
So three swings, three misses. Although the diphoton bump wasn’t really a swing, as such. Unlike the Higgs (but like the Spanish Inquisition), no one expected it, no one was looking for it. It was just noticed in the data.
We continue to explore outwards, Mars, Venus, Mercury, Vesta, Ceres, Jupiter, Saturn, Pluto,… so much exploration there.
We likely will return to the Moon, mine the asteroid belt, and live on Mars, all in the fairly new future.
But we seem stymied by the very small, the quantum world.
Ironically, it seems to fit the general mode of humanity. We look and explore outwards with such force and vigor, but we don’t seem to direct quite so much energy looking inwards or reflectively.
Wouldn’t it be interesting if learning to look inwards ourselves led us to insights about the quantum nature of reality? Yes, fanciful imagining, but it is kind of weird how outward and upward are our natures!
Stay quantum, my friends!