The LHC Gets Credit for Atomic Theory

A wonderfully incoherent press release came across my EurekAlert feeds yesterday, with the headline "Particle physics study finds new data for extra Z-bosons and potential fifth force of nature." You can tell it's going to make no sense at all from the very first sentence:

The Large Hadron Collider is an enormous particle accelerator whose 17-mile tunnel straddles the borders of France and Switzerland. A group of physicists at the University of Nevada, Reno has analyzed data from the accelerator that could ultimately prove or disprove the possibility of a fifth force of nature.

As the largest science instrument ever built, the LHC has the science community buzzing with excitement as it may help in understanding the inner workings of Nature.

Remarkably, some of the new physics that may be studied at this $6 billion facility can be probed using low-cost experiments fitting in a typical laboratory room.

In a forthcoming Physical Review Letter article, the University of Nevada, Reno physicists are reporting an analysis of an experiment on violation of mirror symmetry in atoms. Their refined analysis sets new limits on a hypothesized particle, the extra Z-boson, carving out the lower-energy part of the discovery reach of the LHC.

These paragraphs manage to be spectacularly wrong on several fronts, starting with the fact that the LHC is not in any way involved in the parity violation experiments. What's even better, though, is that the actual work described is theoretical-- the paper in question is most likely "Precision determination of electroweak coupling from atomic parity violation and implications for particle physics", whose abstract is:

We carry out high-precision calculation of parity violation in cesium atom, reducing theoretical uncertainty by a factor of two compared to previous evaluations. We combine previous measurements with our calculations and extract the weak charge of the 133Cs nucleus, Q_W = -73.16(29)_exp(20)_th. The result is in agreement with the Standard Model (SM) of elementary particles. This is the most accurate to-date test of the low-energy electroweak sector of the SM. In combination with the results of high-energy collider experiments, we confirm the energy-dependence (or "running") of the electroweak force over an energy range spanning four orders of magnitude (from ~10 MeV to ~100 GeV). Additionally, our result places constraints on a variety of new physics scenarios beyond the SM. In particular, we increase the lower limit on the masses of extra $Z$-bosons predicted by models of grand unification and string theories.

This is a very nice result, but it has nothing to do with the LHC. For one thing, the LHC hasn't even been turned on all the way yet, so there's no way it could have provided any data for this paper. More importantly, though, this is clearly described as a new theoretical analysis of existing experimental data, a fact that the press release manages to completely obscure.

What's really going on here is a re-analysis of a precision measurement of transitions in cesium atoms, made several years ago by Carl Wieman's group at JILA. The idea here is that there are pairs of states in cesium that are not connected by the normal transition mechanisms. A electron in one state can not move to the other state by absorbing or emitting a single photon, because that transition would require changing the symmetry of the atomic state in a way that's not normally allowed.

Exotic theories of particle physics provide a way around this principle, though. If certain types of hypothetical particles exist, it would be possible to make these transitions, thanks to interactions between these new particles and the one we already know about. Thus, a measurement of the probability of these transitions gives you a way to detect these exotic particles without needing a multi-billion-dollar particle accelerator.

The tricky part of these experiments is that the physical situation is very complicated. In order to put a good limit on the properties of the hypothetical particles, you need to be able to completely rule out all other effects, which means that you need to understand the physics of the electron states extremely well. That's very hard to do, and the theoretical uncertainty due to limited knowledge of the atomic states is one of the biggest limitations on these experiments. People like Tiku Majumder at Williams have made very good careers for themselves by measuring atomic properties that can be used to test these theoretical models, in order to be sure that these parity violation experiments are interpreted correctly.

The paper in question is a new theoretical analysis of the Wieman group's data, which allows them to improve the limits on exotic particle properties due to those experiments. What they find is in complete agreement with the Standard Model, indicating that no new physics has yet been detected. This means that one of the hypothetical new particles that could lead to parity violation, the "extra" Z boson, if it exists, must have a higher mass than the previous limit would've predicted.

This connects to the LHC only in a prospective way. That is, this measurement further restricts the range of parameters that these particles could have, which tells people where to look whenever they finally get the accelerator working. That's it.

The attempt to tie these results more closely to the overblown LHC hype led the writer to say things that are manifestly untrue, making this one of the worst press releases I've seen in some time.

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It seems that PRL has a policy of encouraging authors to have their institutions issue press releases aimed at the public whenever they get an article published in the journal, no matter how speculative and minor the result. This has led to a long string of press releases and press stories like this one, which do nothing but misinform and mislead the public. Someone should get after PRL to put a stop to this. They should encourage authors to avoid having press releases issued unless their result is really important, and to take some responsibility to ensure that press releases discussing their work are accurate, not full of hype and misinformation.

Have you considered the possibility that the author has a pay-by-mention agreement for the LHC? It sure does push traffic...

(Sarcasm in this case, but it wouldn't really surprise me to hear that this is actually taking place.)

@Peter #1: It's not just PRL; the other GlamourMags (Nature and Science) also seem to have this policy. And the other GlamourMag press releases, at least the ones I am familiar with, also have accuracy problems--usually not as egregious as this one, but still not fully accurate.

A recent case in point would be the the Science paper whose publication last year I learned of from my mother--she's retired, so she saw the news report on one of the 24 hour cable stations. The press release claimed that a Major Controversy in my subfield was definitively settled in favor of Hypothesis A. The first thing I noticed when I read the actual paper was the statement in the abstract that it was only "likely" that Hypothesis A was correct, and on reading the body of the paper I found that while the authors made a good case, it was not the slam dunk for Hypothesis A that was claimed in the press release. From personal observation, the Major Controversy rages on, with plenty of evidence both for and against Hypothesis A.

By Eric Lund (not verified) on 29 Apr 2009 #permalink

The Standard Model arrives massless. It is curve-fit by explicit insertion of a dozen fudnamental masses. Said insertion is jury-rigged with the Higgs mechanism. Physics arrives achiral. Yang and Lee! Quantum gravitation theories require supplementing Einstein-Hilbert action with a parity-violating Chern-Simons term. Empirical chiral stuff is discretely incorporated then vigorously ignored as a trend.

Heavy atoms are detectably left-handed from nucleus-electron Z^zero exchange. Nobody dare conjecture the vacuum itself is chiral in the massed sector because that statement is testable: A parity Eotvos experiment contrasting cultured single crystal test masses of left- and right-handed quartz (opposite parity atomic mass distributions). A non-null net output would elicit displeasure. Somebody should look.

Someone should get after PRL to put a stop to this. They should encourage authors to avoid having press releases issued unless their result is really important, and to take some responsibility to ensure that press releases discussing their work are accurate, not full of hype and misinformation.

I think this is going a little too far. PRL is, in theory, the place for the most important and general-interest results in the physics community-- at least that's what their refereeing guidelines say. Papers published in PRL ought to be worthy of press releases from most institutions. This specific paper (assuming the thing on arxiv is the right one) is absolutely deserving of some mention.

The problem isn't the fact that they're putting out press releases, the problem is that they're putting out really bad press releases. The right solution is to demand better-written press releases, not to avoid publicizing the work at all.

One of the major problems we have in physics is that we don't do a very good job of communicating our results to the public. I think the idea of putting out more press releases about physics results is a good idea, they just need to work on the content of the releases.

I wonder if it is an accident that the Eureka Alert link is currently broken. Maybe the authors read the press release about the same time you did and threw the kind of fit I would have if I saw that kind of nonsense written about my work.

I blame the "news" staff at Nevada-Reno, who are probably more skilled at dealing with sports than science.

Seriously, though. The flacks write as if some particle had been discovered when all they did was come up with a result that "is in agreement with the Standard Model (SM) of elementary particles." They give journalism a bad name.

By CCPhysicist (not verified) on 29 Apr 2009 #permalink

I wonder if it is an accident that the Eureka Alert link is currently broken. Maybe the authors read the press release about the same time you did and threw the kind of fit I would have if I saw that kind of nonsense written about my work.

I don't know about fit-throwing, but if you go to the next post, you'll see that they did, in fact, decide to correct the errors. I got email from Andrei Derevianko this afternoon saying that the errors were due to embellishments by their press office, and were being corrected..

Chad,

I think there are something like 40-50 articles in each weekly issue of PRL. Putting out press releases for all these articles (and for all those at other journals with equivalent claims to significance) would ensure that no one in the press reads any of them. Ideally the editors of PRL should be identifying the most significant articles they publish, and trying to get press attention for those, not trying to get press attention for all their articles. I gather the APS "Physics" online site is an attempt to do something more along these lines.

The question of how the inaccurate text got into the press release is a separate one, but you can't entirely blame the person in the press office for this. The supposedly accurate story you link to at

http://www.unr.edu/features/08-09/atomClock/

starts off with a large dollop of LHC hype, and includes some other highly misleading material. The summary of the paper claims

"At the same time, a major goal of the LHC is to find evidence for supersymmetry (SUSY), one of the basic, yet experimentally unproven, concepts of particle physics. Our result is consistent with the R-parity conserving SUSY with relatively light (sub-TeV) superpartners. This raises additional hopes of discovering SUSY at the LHC."

This makes no sense. I don't see anything about this (perfectly interesting) null result that says anything about the possible existence of superpartners, and this claim doesn't appear in the paper (where any referee probably wouldn't allow it).

Well, at least they didn't do the usual thing these days, and claim to have a "test of string theory"....

I think there are something like 40-50 articles in each weekly issue of PRL. Putting out press releases for all these articles (and for all those at other journals with equivalent claims to significance) would ensure that no one in the press reads any of them. Ideally the editors of PRL should be identifying the most significant articles they publish, and trying to get press attention for those, not trying to get press attention for all their articles.

I'm not saying that the APS should put out releases for all the articles-- they do highlight a handful of articles from each issue as "Editor's Suggestions," and feature a couple in Physics, which is as much as I would expect from them.

I think it's perfectly reasonable for the press offices at the home institutions of the authors to put out releases, though, if they so choose. That's what this was, and I don't have any problem with the idea of them doing a release, just the execution of the release.

(I've also received an apologetic email from a guy in the U. of Nevada- Reno press office, saying that they pulled the release from EurekAlert, and are sorry for the whole mess.)

As for the specific claims about high energy physics, I haven't read the paper carefully yet (though I'll try to say something positive about it soon, to make up for the negative attention), so I can't really evaluate those claims. I did not find the hype level of the article on their web site to be excessive, but you're more sensitive to that sort of think than I am.

Hi Chad,
By my reading, this new theoretical analysis of old-ish data shows a slightly stronger than standard weak coupling, indicating (at 50% CL) the possible existence of a Z' particle. This is good-ish news for the Pati-Salam, so(10), and E8 models, which all predict this particle. But the bad-ish news is that the new mass limit puts it above initial LHC range. In any case, it's fantastic that this result came from high precision atomic experiments. I hope there's going to be more work on this.
Best,
Garrett

Thanks for clearing this up..I read it and was very, very confused; as you say, the LHC isn't even up yet!

The press release sounded tantalizing...New Force of Nature and all that.

This press release is a perfect example of how badly physics is presented to the public. Even for me, who has just enough education and awareness to say "wha....???", then find the answers from blogs like yours. I can just imagine the regular person who just throws up their hands and gives up.

What's the answer? I dunno. But thanks for doing what you do anyways.

The project I work on had some data published last year. The journal editors were excited and wrote a press release which was *spectacularly* wrong and suggested that we had actually discovered dark matter... We managed to politely set them straight on what the paper was actually about, but since then I really distrust those press releases.

Admitting to "Embellishments" in press release, that is, PR guys/gals purposely not telling the truth or adding positives that aren't there... That makes me nervous. How do we trust any of the releases from these major players, then?

By sister of phys… (not verified) on 01 May 2009 #permalink

O is One

Changes never end
That is never change everâ¦â¦
Because it had just only
one thing is the change
without anything else everâ¦.
Sometime I try to find to
some answer
for the true of lifeâ¦â¦
What is the life?
And why all of everything happens
at here in the Galaxy
and the world?
We could to knows
in the first time of the Universe
it could start come from
nothing or empty
by without the empty
or No the empty though
No everything or itâs the âOâ
But in certainty so
âNothingâ is a thing
or âOâ is the one like-wise
So I can see in the first time
of the Universe happened
it could not be start
come from the empty
because itâs have a thing
being before all the times
that is nothing
cause the meaning of nothing
that is a thing
Yes, a thing that is the empty
but that itâs not the empty
like we understood
Something we called itâs the empty
but not be so like that
And what is it?
All that I can see a thing
it still never change ever
So could you believed or not?
Everything and every-life
never to be lost out of the Galaxy
or all the Universe
And that because
when all everything to the end
it will became nothing empty again
but no lose all
because nothing
that is a thing one more
So I have asking you
How everything happened
at here in Galaxy or the Universe?
When everything it can happens
and when it lost out of the Universe
Why it cannot come back again?
Yes or not
But in the true of everything
It will be come back
to start again forever
Because all the Galaxy of
the Universe all of everything
all is the One
And nothing empty is the One
It is the One never change
Never lose
Never end ever
Everyone have been so like this
We are everyone never knew
Yes or not
That we have been circle never end
Between birth and die like everything
Cause all space in the Universe
Without back side
Or out side of space
And that is âOâ nobody
When whatever life to the end
Or die and the Universe
No space to keep and hide them
So everything every-life
that to be lose or die
When the time of them come
All will start to happen again
And circle never end
Itâs not the reason
If you will talk about is
When all everything to be lose
And to the end
And it will not come back
To start again anymore
The most important that is
all everything can happened
in this now when it can happens
And when it lost it will must
turn back to happens again
Everything that the eyes can see
in this now that is
the reasons and most important
itâs the answer of everything
that be lost and
it will happens again ever
When everything
thereâs in front of the eyes
in this now
all happened from the empty
and when it lost and gonna be
the empty and from the empty
that become back as everything
all that the eyes can see
in this now
like in the first time of
the Universe all thatâs nothing
so but everything happens
as that you can knew
when you read that I wrote
and how you think of about it
But everything
cannot be as usual forever
So when all everything
changes never end
that is never changeâ¦...
And I can see to something add up
That is in the Universe or Galaxy
In certainty
Universe without the time
But the time is distance
connection with speed
When it has
changes never end
Thatâs never change
Thatâs never had
the timeâ¦â¦â¦â¦.
The walking of the time
It always ran never stop
Every-time when it walking
It will always make space
and distance add up to ever
There happens from
The empty making
chemical reactions
with atoms of everything
Explain is everything
in the Universe that
the eyes can see and
we can touch to knows
all that is one piece
and nothing empty
that is piece one more
the pieces both make
reactions together
And if whenever the time
to the end real or stop,
All space, distance and speed
It will be lost with the time
And everything is âOâ
When it is âOâ
That is one piece (nothing-empty)
In this case O was One finished
And this piece will start to make
new reactions with piece one more
(or new nothing-empty one more)
together again never had to stop
right here it will new atom happens
for every-time ever
In the true nothing-empty
it will always have stand forever
whenever that have anything happen
it will have nothing happen follow
altogether forever
(itâs automatic time-real)
All everything every-life
never to be eternal ever forever
: Nothing-empty is
center one of the Universe
center all of the time
Everything always had changes forever
That is all the reaction of reasons
That talk about is nothing-empty
and everything make energy by
change itself forever

E-mail artistton@hotmail.com

By Pure Empty in … (not verified) on 13 May 2009 #permalink

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By ANTARPREET (not verified) on 03 Jun 2009 #permalink

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By ANTARPREET (not verified) on 03 Jun 2009 #permalink