Neutrino Soup Makes a Thin Gruel, Tech Theory

Why Look for the Higgs Boson?


One possible signature of a Higgs boson from a simulated proton-proton collision. It decays almost immediately into two jets of hadrons and two electrons, visible as lines. The proton beams would enter the picture from the east-southeast and west-northwest. Image from Wiki

Good morning everyone.

Particle physics is a rather complicated affair and uses a host of specialized terms and concepts that the majority of people aren’t familiar with, and I find them difficult to explain succinctly in the handful of words that I’m allotted here, or without glazing over the eyes of the casual reader. I run into the same problem when attempting to explain the functioning of the valve body in an automatic transmission without using terms like “eldritch devices spawned by ancient squelching horrors from another dimension” or “well guv, it’s bloody voodoo, innit?”. It’s tough.

The other day however, I came across a short video over on Gizmodo that I was unable to watch because it’s a Vimeo video, and Vimeo videos won’t play for me on Gizmodo for some reason, and I find it quite annoying that I have to go to the Vimeo site (nothing against Vimeo, mind you) to watch them rather than just watch them where I’m already at. They work everywhere else, so why not on Giz or the rest of that lot? Could it be from weird site design decisions? Perish forbid. Bloody pain in the butt is what it is, but what can you do? Complain? Hmph. Join Facebook just to login? Oh please, can I? Bah!

Ahem. Where was I…video? What video? Oh yes, that video. I found a video called “The Higgs Boson Explained” which was made by Phd Comics, whoever they are, and I was immediately intrigued. I’d been having such a fun time with the topic, I wanted to see how these guys do explaining the subject to the drooling knuckledraggers, mechanical engineers (same thing, really), and iFone addicts in the audience. Yes indeed, ho ho, it should be entertaining.

The answer is “quite effective, in about eight minutes” as it turns out. Sigh. The video is after the jump.

[vimeo width=”600″ height=”400″][/vimeo]

That was absolutely excellent, wasn’t it? Nice and concise, and I hope they choke, damned showoffs.

Additional Information

I still feel the need to throw more information at you, and because I can, I will. Here is a better chart of elementary particles that shows how the known bosons fit in:


The Standard Model of elementary particles, with the gauge (force carrier) bosons in the last column. Image from Wiki

Here is a chart that shows, more or less, where the main bits fit into the grand scheme of things:


An overview of the various families of elementary and composite particles, and the theories describing their interactions. Fermions are on the left, and Bosons are on the right. Image from Wiki

I trust that all of your questions are now answered.

And just to be nice, here are some pretty pictures of the Compact Muon Solenoid experiment at the Large Hadron Collider at CERN which is busily looking for the Higgs.


Note the beam tube entering the center of the detector. All images from CERN

CMS Detector

Click on the images to enlarge




From Wikipedia:

—Fundamental interactions

—Higgs Boson



  • Number_Six

    I want to work at CERN because their machine is so pretty. I work for a company that drags stuff out of the ground, so our machines are always coated in filth. When I read the word "boson" my brain automatically defaults to the nautical "bosun". This comment may explain some of my difficulty with particle physics.

    • jeepjeff

      Their stuff has to be clean. It's running in super cooled high-vacuum. I did a bit of work in a high-precision physics lab when I was an undergrad (actually, down the hall from one of the teams working on the ATLAS detector), metal parts that were destined for high-vacuum got cleaned in three different high-volatility solvents (ethanol, acetone and I'm blanking on the third… Maybe it was the EPA? No, Dept. of Education… Oops. Wrong speech…). Material prep was a big important thing.

      • The Professor

        When you're trying to bounce protons off of each other, specs of dust can be rather large. In actuality, the supporting machinery and electronics are maddeningly sensitive to dust, very much like the environment of a semiconductor FAB.

        • jeepjeff

          That sounds about right. A few microscopic drops of oil from a vacuum pump can mess up your whole week kind of deal. It was a similar story at the lab I was working in, just on a smaller scale.

    • mr. mzs zsm msz esq

      When I was a kid there was an article in a local paper titled something like "Scientists at Fermilab on the hunt for the Higgs Bozo." The whole article was like that. It was funny but had a simple explanation. The reporter had interviewed a Yugoslavian member of the CDF team that had a thick accent. Man it would be neat if there was a bozo detector though.

      Anyway, neat video, one little thing though. The explanation about the quark with a proton, it only has valence quarks and gluons. In fact the more current visualization is that there are sea quarks in the hadrons (like protons and neutrons). These are quark/anti-quark pairs that from from gluons and annihilate forming gluons once more pretty much constantly. It's like they all cancel though and only the three different colored up and down quarks matter, but there are scenarios where a pair like that can form a meson for example.

      • jeepjeff

        The LHC had its own monumental typo. You should click that link. It's 99% SFW.

        For your second paragraph, it sounds like what you're thinking of is the sea of virtual particles in and around every nucleus. They aren't real, and they cannot become real unless there is a source of energy large enough to comp them their rest energy (ie: mass). The virtual particles can exist thanks to the Heisenberg uncertainty principle, ΔEΔt >= ħ/2. As long as Δt <= 2ΔE/ħ, then a particle with rest mass ΔE can exist without being "real" (it doesn't break any conservation laws for it to pop into existence as long as it doesn't overstay its welcome, Δt). This is one of the mindbending bits of QM, and probably why they left it out of the video (or rather, it's kind of there, it's one (if not the, I'm working from memory here) way that the bit about "anything on the menu, as long as it has less rest mass than 500GeV" works.

        • mr. mzs zsm msz esq

          You're right of course, well except you mistyped nucleus instead of proton, neutron, Barry On 😉 It's just a visualization thing, like with the atom and plum pudding at first then a nucleus with electrons orbiting around like planets in different planes. That was a better thing to imagine once they started shooting alpha particles at gold foil and seeing where things ricocheted or whatever it was that they did. Then the idea of the electron clouds started making better sense – p, f, all that jazz especially made stuff in o-chem make more sense. So instead of saying something like Lattice QCD or whatever soup of letters says you can predict the mass of a proton or neutron now given a powerful enough cluster, truuuuuust me. Well you can say to a person reading Nature, you know imagine a ball and inside are the three quarks and gluons. Well most of the mass is not from those quarks but whats going on with the gluons and quarks instead. But also to be really accurate you need to take into account the sea quarks. It also helps to explain how you smash 'em and these bottom and anti-bottom say can come out. The reader can sit there and think, oh yeah they were around for a little bitty time, makes sense they could fly out when they get smashed real good. Oh and by Nature reader, I mean me. I'm not a physicist 😉 I do think that the image with sea quarks will become more common than the one with three balls and swiggles in the end though on web sited and text books.

        • The Professor

          Ha! I've written it like that more than once, usually by accident.

  • skitter

    Per usual with this kind of post, I feel the need to lie down.
    It's like some completely ambiguous bedtime story.

    • jeepjeff

      It's not like we were talking about entangled states. That really is ambiguous. This stuff is comparatively straight-forward.

      • The Professor

        But he does illustrate the problems you run into when trying to write articles for the general public about the more arcane areas of science. In skitter's case, he just happens to think about things rather deeply and gets boggled by the incredible nature of things. Nothing wrong with getting boggled by some of the concepts that we deal with, it indicates a functioning brain.
        No, it's when I explain a technical concept as simply as I am able, and I get reactions as if I suddenly started reciting love haikus in classical Japanese that I get frustrated with my shortcomings as a writer wannabe.

        • I've found you to be equally lucid on all topics.

          • The Professor

            Hmph. I'll choose to take that as a compliment.
            You're probably still annoyed that I found you skulking in the comments of the 'Saab Replacement' post, rather than doing what you should have been doing, which is filling young minds with drivel gravel enlightenment information they can use.

          • Yesterday was enlightenment day. We launched and tracked small, instrument-laden balloons from campus.

          • The Professor

            Out of curiosity, what's your recovery rate on the launched packages? Or do they not float that far away?

          • About 50-50. The smaller ones only have a temperature-sensitive transmitter beacon, nothing that reports position. We've got directional antennae pointed at them, but we don't even attempt pursuit, so it's a question of someone stumbling across one and bothering to contact us about its return. They usually go about twenty miles or so. We launch the larger ones in eastern Washington where it's easier to pursue in any direction (and they've got onboard GPS which usually transmits until impact), but even then we lose about half of them. Sometimes we'll get them back a year or so later when someone else happens to come across the remains. The big ones also go in the range of tens of miles from the launch site before popping. We always aim to fill them enough so they'll rise to the point of bursting, specifically so they won't drift for days before leaking enough to descend.

          • The Professor

            ~50% sounds pretty good for the non-GPS variety, actually. In my head I was thinking that ~10% would be typical. Wrong again. What is surprising to me is how adding GPS to the instrument package doesn't seem to boost the recovery rate.
            Another mystery of the universe to ponder.

          • We could probably do better with the GPS if we had to, but as matters stand, just because it transmits until impact (usually), that doesn't necessarily mean we receive a useful fix all the way down. The GPS has to share time with the other data channels, so we get an update perhaps every twenty seconds, depending on the setup. Couple that with the frequent loss of the last transmission or so if we're not yet close enough and that's plenty of time for it to drift with the wind a fair distance before landing. If it comes down in an uneven and/or vegetated area, sometimes the recovery team doesn't find it before dark, at which point experience has taught us to call it quits for the long drive home, especially if nobody had an eye on its final descent. We've found that even if the transmitter is still working, we can't pick up its signal on the ground until we're pretty much standing on top of it.

            We do a better job of retrieving the big ones ourselves whereas the public seems more likely to find the small ones for us (probably due to population density around Seattle), so overall it's a wash.

        • jeepjeff

          I was trying to make an awful joke. Entangled state ==> physical embodiment of ambiguity? Yeah. Nevermind, it was dumb.