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The Proton Just Got Smaller
inflame writes "A new paper published in Nature has said that the proton may be smaller than we previously thought. The article states 'The difference is so infinitesimal that it might defy belief that anyone, even physicists, would care. But the new measurements could mean that there is a gap in existing theories of quantum mechanics. "It's a very serious discrepancy," says Ingo Sick, a physicist at the University of Basel in Switzerland, who has tried to reconcile the finding with four decades of previous measurements. "There is really something seriously wrong someplace."' Would this indicate new physics if proven?"
"'The difference is so infinitesimal that it might defy belief that anyone, even physicists, would care"
Does this sentence bother any one else? Just me?
Just remember, dear protons:
Size matters not. Look at me. Judge me by my size, do you? Hmm? Hmm. And well you should not. For my ally is Physics, and a powerful ally it is.
two hydrogen pals are sitting on the curb, sipping from their 40s. One says to the other "I think I've lost an electron". The other says "Are you sure"? To which the first replies, "Yeah, I'm positive".
~.~
I'm a peripheral visionary.
That's actually the writing on paper bags on Algerian Airways.
this is why i never listen to scientist.
they're always lying, and making me pissed.
fucking protons, how do they work?
THL phish sticks
> 4% sure does seem significant. But more interesting is that the measurement is thought to be much more precise because of the method of measurement.
No. The interesting thing is that the proton size is now shown to be different than expected from theory. Which means that the theory is wrong. Which is the first step in exciting new physics.
Maybe, but this is still surprising. Measure a grape with a metre rule, you should still be able to say 'it's between a centimetre and a centimetre and a half.' Measure it with a micrometer, and you'd expect to see a result like 'It's 1.2144 centimetres.' If the micrometer instead measured the grape at 0.7218 centimetres, well, you'd be puzzled. First of all, of course, you'd check you were doing it right. You'd examine your micrometer and make sure you were operating it correctly. You'd recheck how you measured it with the metre rule - is it zero from where the number is printed, or from the edge of the ruler, is the ruler maybe worn down at the edge?
But if all that checked out and you still had this discrepancy, you'd start to wonder if your ruler and your micrometer were really measuring the same units.
Hence the suggestion of new physics. Theoretically the muon should act like a heavy electron - interacting with the proton in just the same way, so that it can be used as a more precise probe on the size of the proton. It would be the micrometer to the electron's metre rule. If it doesn't - if the muon interacts with the proton in some unexpected way so as to throw the measure off - then we've discovered something beyond the standard model.
There are quite a few indications that there is physics beyond the standard model - heavy neutrinos, the abundance of matter over antimatter, the dark matter - and so if we can add this to the list then maybe it can help pin down just what sort of a new theory we're looking for. We've got to have something to do once the good people of Geneva finally hammer us out a Higgs, after all :-)
Real Daleks don't climb stairs - they level the building.
I shrunk the proton. The kids are fine, though.
Physicist here.
What's the diameter of the earth's magnetosphere?
About 10 Earth radii, defined as the point where the Earth's magnetic field is stronger than the solar wind and thus becomes the dominant force on electrical particles.
Similarly, we define the proton's radius in terms of its charge distribution. See how easy that is? It only takes a simple definition to make a word like 'size' meaningful.
And in the case of the proton is *is* meaningful, because you are incorrect about the proton being a singularity. The proton is composed of three quarks, each with their own charges and charge fields.
The quarks inside a proton are held together by strong force interactions. So any change in the measurable size of a proton is a change in what we know about the strong force. This is significant. Either the strong force is 4% stronger than our calculations predict, or there is another mechanism that is squeezing that proton's charge field down. Another force? Another particle? It'll be exciting to find out, now that we know there's something there to find.
The journalists who write about science often use bad, confusing, or just plain nonsensical terms. But it's almost always the journalists, and you can't really fault them for dumbing down their story to appeal to the largest group of readers. Whatever you do, don't blame the scientists. They are doing good work. It's not their fault if journalists relate it improperly, nor is it the scientists' fault if you don't understand the explanations.
Genocide Man -- Life is funny. Death is funnier. Mass murder can be hilarious.
Which means that the theory is wrong
At best it means either the theory or the experiment is wrong, and the "wrong" can vary from mundane to really interesting, with the vast weight of probability on the side of mundane.
The structure function of the proton is not simple, and calculating it depends on QCD approximations that are even less simple. The notion that it can be characterized by a single parameter is questionable.
Muons probe a very different part of the proton structure function than electrons. Muon orbitals are much smaller than electron orbitals, so protons look even less like a point mass to them. As such it is not surprising that they would result in a significantly different value for a single parameter in a particular model of the proton, even if the experiment is not in error somehow. By far the hardest part of the structure function of nucleons to model in QCD are the tails, and that is exactly what muons will be most sensitive too.
This is how experimentalists react to anomalous results: the most probable explanation, always, is that the people doing the work screwed up. We then set out to prove how they screwed up. If we can't, we start to think about other corrections seriously.
Theorists will of course have no difficulty explaining this result, even if it later turns out to be incorrect. But even if the results are correct, they will almost certainly be accounted for by relatively insignificant tweaking of QCD estimates of the proton structure function, which is good solid science, but not the kind of great big deal that TFA seems to want to make of it.
Blasphemy is a human right. Blasphemophobia kills.
The journalists who write about science often use bad, confusing, or just plain nonsensical terms. But it's almost always the journalists, and you can't really fault them for dumbing down their story to appeal to the largest group of readers.
Sure I can. Because it breaks the story, making it false. This confuses the readers further and makes the story have less value than not running the story at all. Yes I know the REAL job of newsies is to attract eyeballs to sell to advertisers. But they pay for the eyeballs by offering information, so "dumbing down" the story until it's worse-than-useless is outright fraud. (And it's a big part of why the old news media are dying.)
English is a very expressive language. It's usually possible to come up with wording that can get the meaning across just as clearly and just about as tersely. For instance, in this case the proton didn't just "get smaller" i.e. suddenly change size. "New measurement technique finds protons unexpectedly smaller." is my first attempt - and I'm NOT an expert in such composition. News writers are SUPPOSED to be experts in this, so there's no excuse for them.
Slashdot had an article and discussion on this - and science popularization - a few days ago.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
> oh well, i'm figuring that he's probably right seeing as science is just a bunch of atheistic dogma anyway...
Considering that Max Plank said:
"Eine neue wissenschaftliche Wahrheit pflegt sich nicht in der Weise durchzusetzen, daß ihre Gegner überzeugt werden und sich als belehrt erklären, sondern vielmehr dadurch, daß ihre Gegner allmählich aussterben und daß die heranwachsende Generation von vornherein mit der Wahrheit vertraut gemacht ist."
which is translated as
"A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die, and a new generation grows up that is familiar with it."
or paraphrased as the common English phrase:
"Truth never triumphs -- its opponents just die out."
"Science advances one funeral at a time."
You might be right on the dogma bit.
http://en.wikiquote.org/wiki/Max_Planck
My name is Ingo Sick. You cast doubt on the Standard Model. Prepare to die!