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Interviews: Ask Physicist Giovanni Organtini About the Possible Higgs Boson Disc
Giovanni Organtini of Italy's National Institute of Nuclear Physics (well, Instituto Nazionale di Fisica Nucleare) has agreed to answer questions about the recent observations of a particle consistent with the Higgs Boson. Dr. Organtini is part of the CMS experiment at the Large Hadron Collider. He is careful to note that while the researchers "[believe] that this new particle, with a mass 125 times that of a proton, is the famous Higgs boson," they "need to study that new particle more deeply in the next months to be conclusive on that. Organtini likes free software (he's written Linux device drivers, too) and has his own physics-heavy YouTube channel, mostly in Italian. Please confine questions to one per post, but feel free to ask as many as you'd like.
How much do you hate people who say "disc" instead of "discovery" and lead halfwits everywhere to believe the Higgs particle is disc-shaped somehow?
I'm betting they're talking mass-energy when they refer to the particle's mass, that's the norm for particle physics, and one of the reasons masses are measured in GeV (technically GeV/c^2) instead of molar-masses or something as is done in chemistry.
Basically there are three distinct phenomena that all go by the name "mass" since, in all experiments to date, they are invariant with respect to each other.
(1) mass-energy: e=mc^2, how much energy would you get out if you annihilated the particle
(2) inertial mass - F=ma, how much an object resists acceleration from a force
(3) gravitational mass: f = G * m1*m2 / r^2, this is the gravitational "charge" that determines how strong the force of gravity between objects is, highly analogous to electrostatic charge though much weaker, to the point of being essentially undetectable in particle accelerator experiments.
From what I understand the Higgs field is probably responsible for the latter two, however the first is still an inherent property of the particle itself.
Oh, and incidentally top quarks are actually even more massive at 171GeV, and Bottom and Charm quarks are both pretty beefy at ~4.2 and 1.3 GeV, respectively, versus the puny 2.4 and 4.8MeV of the Up and Down quarks that make up normal matter (which actually gets most of it's mass from gluons) http://en.wikipedia.org/wiki/Quark#Classification
--- Most topics have many sides worth arguing, allow me to take one opposite you.
ATLAS generates 23 petabytes of raw data per second. A large computer cluster near the detector identifies which events to store amounting to 100 megabytes per second which is around 1 petabyte of data per year. (Straight from wikipedia)
The actual analysis of the data requires multiple large computer clusters world wide. I believe the data is available to anyone with the expertise and knowledge required to do any meaningful data analysis. Oh and having a spare cluster sitting around with nothing to do probably helps as well.
This is slashdot, so I'm going to assume I can at least share some "mathy" parts of it (not really the whole thing).
The Higgs Field is represented by two complex numbers. It is a field, therefore, it has a value in every point in space, kind of like how the temperature across the world varies depending on where you are. In that example, the "temperature field", I'd guess, is represented by a real number at every point.
Now remember that each complex number can be written as two real ones given the form:
z = a+bi
therefore, technically, the Higgs field is not just two complex numbers but it can be thought of as four real numbers. So think of it as being a bundle field with four numbers for each point. Each number, turns out, becomes a particle.
So there are four particles that come out of the Higgs field. Three of them turn out to be components of the Weak bosons (W+, W-, Z_0), as needed to explain why they have mass while photons don't. But there is one field left. This is identified as a new boson, the Higgs Boson.
So, the Higgs Boson is actually just _part_ of the Higgs Field. It isn't like the photon, which is the particle of the whole EM field. Oddly enough, the Higgs Field itself is massless, I think. But the Higgs Boson recieves mass the same way the other three Weak bosons recieved mass, by the Higgs Mechanism.
Really, you can get all woowy with the conceptual part of the Higgs Mechanism but it really is just a neat math trick that I can't really explain here. Essentially, you start with a mathematically description of the particles with mc^2=0 (remember Einstien's equation, E=mc^2 for the energy stored in mass), ie, the particles are massless. After the math trick involving the Higgs Field (not just the Higgs Boson!) you obtain a term that looks like mc^2, so it's like the mass term arises spontaneously without having to put it in there a priori. Hence how we say the particle has "acquired" mass: We started out modeling out particles as massless but all of a sudden, the math tells us it has it.