BenTheMan

Yeah sorry--- They say "calculations have been preformed using the quenched calculation..." which I took to mean that THEY used that approximation. Sverian, PM me and I'll send you a copy of the article.

Absolutely. The New Scientist article says something like "Until recently, lattice QCD calculations concentrated on the virtual gluons, and ignored another important component of the vacuum: pairs of virtual quarks and antiquarks."...not that I trust whatever journalist who wrote this knows what they're talking about. But this doesn't seem to mesh with the "quenched" approximation. I probably looked too quickly at the article

No---I skimmed through the article the other day, and I seem to recall that they were working in that approximation, but I could be wrong. Like I said, it is confusing because they make some claim in the New Scientist article about vacuum fluctuations, which is what the quenched calculation does away with.

Yeah I don't know why they published in AAAS. I read the paper, and I didn't see anything about a proton mass, and I can't recall all of the lattice terminology---I do recall that they're using the quenched approximation, which seems a bit odd. In this approximation, you turn off the quark-anti-quark virtual pairs (I seem to recall), but the New Scientist article makes a big deal about the fact that this is what they were calculating.

I think you guys are on different planets entirely

That's what you're saying when you say "bosons and fermions are the same".

AB-BA and AB+BA are the same?

Well, I don't know if "making the theory fit the data" is always a bad thing I'm sure if you could explain electroweak symmetry breaking without a higgs, in a similarly economical fashion (i.e. not "extended walking technicolor"), then you'd be invited many places to give many talks. The situation with the higgs mass is a bit intricate---the ONLY way we know how to break symmetries is to give scalar particles VEVs. Naturally, scalar particles are heavy, but we have a spontaneously broken symmetry at a low scale. So what can we do? Similarly, you could ask why the electron should have such a small mass and the top quark such a large one. Or why all three neutrinos have more or less the same mass, but none of the quarks and leptons do. PS Sverian---do you know a good review of the precision electroweak observables/data? I have this Phys Rept article by Heinemeyer, Hollik and Weiglein.

I agree. I've never really met anyone who votes for Dirac neutrinos, except possibly Paul Langacker.

What is your opinion on this, Sverian?

Maybe there's not much discussion because people don't understand what "tuning" is. This has been my experience, at least---most non-physicists don't see a real problem with it because they don't understand the problem. The example I use is this: A + B - C = D Suppose I tell you that A, B, and C are all real numbers that are between 0 and 10. What do you expect D to be? Or, conversely, given all real numbers between 0 and 10, what would a random selection of A,B, and C produce for D?

There was a rumor that he was going to move to the Perimeter Institute.

Most?

I think, if you're willing to accept a fine tuned higgs mass, then you have a real problem model building. If you're willing to throw out "naturalness" as a criteria, then publishing hep-ph papers should be easy So how do you build models, if you only have to satisfy the LEP data and the WMAP bound?

http://www.bnl.gov/RHIC/docs/rhicreport.pdf See page 11 and following.