Comments on: Frequently Asked Questions About the Higgs Boson

By: Dan Riley

Dan Riley — Wed, 07 Mar 2012 18:34:22 +0000

The mass comparison section seems badly garbled. One proton is indeed about 1 GeV mass, but a gold atom is 79 protons and somewhat more neutrons, so about 190 GeV mass. 91 GeV is one Z boson, or roughly one zirconium atom. 125 GeV is about one iodine atom.

A grain of sand, by comparison, is around 10^20 (that’s a one followed by 20 zeros) molecules, mostly silica, so the putative mass of a single Higgs boson is minuscule compared to the mass of a grain of sand.

Finally, the battery comparison mixes up Volts and electron-Volts, which aren’t comparable.

For refs, try plugging “higgs mass” into Wolfram Alpha, or see the Wikipedia “orders of magnitude (mass)” page.

By: Rusty

Rusty — Wed, 07 Mar 2012 16:25:45 +0000

“1 GeV is equivalent to the mass of a proton or the mass of one gold atom. It would take a mass of 91 GeV to equal a very course grain of sand…”

I’m missing something in this statement. How can 1 GeV be equivilent to both the mass of one proton and the mass of one gold atom (which contains 79 protons and a somewhat similar number of neutrons)? And the idea that a coarse grain of sand could contain just 91 protons doesn’t seem even slightly plausible. What am I missing?

By: Adrian the Rock

Adrian the Rock — Tue, 06 Mar 2012 21:10:34 +0000

Surely the mass of a gold atom is a lot more than 1Gev? I make it ~ 197 x 0.931GeV = 183.4GeV.

By: Gavin Flower

Gavin Flower — Tue, 06 Mar 2012 20:52:29 +0000

“1 GeV is equivalent to the mass of a proton or the mass of one gold atom. It would take a mass of 91 GeV to equal a very course grain of sand, like uses for patio construction, (assuming that grain has a mass of 0.011 grams).”

Surely there are many millions of protons in 0.011 grams, so the grain of sand would require considerably more than 91 Gev? Or have I missed something obvious?

Gold is about 197 AMU, which as I understand it, equivalent to about 197 protons, and since aproton is a bit under 1Gev, a Gold atom is almost 200GeV – a lot more than 91 GeV for just one atom!