Track your comments!
[x]


When you register, comments on your articles and replies to your comments appear here. Register Now!

Sign in to your account
[x]

Not a Scientific Blogging member yet?

Register Now for a Free Scientificblogging.com Account

  • Customize your profile with pictures, banner, a blogroll and more.
  • Leave comments on articles, add other members to your friend lists, chat with people on the site.
  • Write blog posts that can be seen by hundreds of thousands of readers.

It's free and it only takes a minute!

Already a Scientific Blogging member?

Sign In Now

Banner
By Georg von Hippel | April 13th 2009 12:15 PM | 4 comments | Print | E-mail | Track Comments
.

More Lattice Points articles

All

About Georg von Hippel

Georg von Hippel is a theoretical physicist researching lattice QCD, the theory describing the strong interactions that bind quarks into hadrons. He obtained his PhD from the University of Cambridge


... Full Bio

So after having eaten all those chocolate Easter eggs you come to realize that the bathroom scales now show your weight to be even further from what it ought to be for your own good, and as a scientifically minded person you decide to blame it all on the Higgs field; after all, as everyone knows from reading the popular press, it's the Higgs field that gives elementary particles their mass.

Well, you're doing the Higgs a severe wrong, because it isn't to blame for your weight problem at all (unless you're a top quark or a B meson, in which case your life expectancy is way to short for you to even read the first line of this post). The real culprit is Quantum Chromodynamics (QCD to its friends).

While it is true that the fundamental particles (like electrons or quarks, or the W and Z bosons that mediate the weak interactions which are responsible, e.g., for beta decays) obtain their masses through their coupling to the Higgs field, the masses of the elementary particles making up all of ordinary matter (the electron and the up and down quarks) are quite tiny. Take for example a hydrogen atom: the electron's mass contributes only about 0.05 percent of its mass, while the remainder is the mass of the proton. And the masses of the up and down quarks are only about 2 percent of the mass of the proton.


I deal with small things, not giant Easter eggs, so your tight pants today are not my fault - Love, Higgs Boson.

So where does the rest of the mass of the proton (and hence of the atom, and hence of that surplus fat) come from? The answer lies in the most famous equation of the world, E=mc2, which asserts that mass is a form of energy, and that conversely all energy has mass. The vastly greater part of the mass of the proton (and hence ... you got it) comes from the energy of the strong interactions that bind the quarks together, and those interactions are described by QCD. Computer simulations of QCD indeed show that the mass of the proton is precisely what QCD predicts it to be.

And even for a hypothetical world where no Higgs field exists and the up and down quarks are therefore massless, QCD predicts that the proton would still have a mass comparable to the one it has in the real world, and hence so would you (well, in fact you wouldn't exist, because the electron would be massless, too, an therefore the Bohr radius would be infinite and there would be no stable atoms at all).

So apologize nicely to the Higgs field (it is apparently quite shy, so don't take offence if your apology is not accepted right away) and heap the blame for your weight problems onto QCD, who is after all the real culprit (although nobody said you absolutely had to eat all those chocolate eggs, did they?).

Comments

Stellare's picture
Higgs is innocent. No doubt. You might however blame it on a varying gravity field though. And boy does it vary. I wonder why nobody has thought about how the mass distribution here on Earth really can make or brake you day - when you go on the scale. :-)

Make sure to follow the results of GOCE (steady state - spatial variation may influence your scale when you travel) - and update yourself on GRACE data (time varying, scale may depend on the season). :-)

Love your article, Georg! :-D Brilliant!

there is however an amusing computation to say that really the Higgs is responsible for the bulk (60%) of the mass of the proton. If there was no electroweak symmetry breaking, and no Higgs vev, the top, bottom and charm quarks would all be massless and wouldn't decouple from the QCD beta functions at their respective scales. As a result the QCD evolution is slower and g_SU(3) blows up at a smaller scale, giving Lambda_QCD around 100MeV. hence more power to the higgs.....

Georg von Hippel's picture
Only if you keep the bare QCD coupling fixed. But you can also adjust the bare QCD coupling so as to keep Lambda_QCD the same in the presence of six light quark species, and since Lambda_QCD is a more physical quantity than a bare coupling, this is what I'd do if I were to create a Higgsless universe.

Interesting post

Add a comment

The content of this field is kept private and will not be shown publicly.
  • Allowed HTML tags: <sup> <sub> <a> <em> <strong> <center> <cite> <code> <TH><ul> <ol> <li> <dl> <dt> <dd> <img> <br> <p> <blockquote> <strike> <object> <param> <embed> <del> <pre> <b> <i> <table> <tbody> <div> <tr> <td> <h1> <h2> <h3> <h4> <h5> <h6> <hr> <iframe>
  • Lines and paragraphs break automatically.
  • Web page addresses and e-mail addresses turn into links automatically.
CAPTCHA
If you register, you will never be bothered to prove you are human again. And you get a real editor toolbar to use instead of this HTML thing that wards off spam bots.