Meantime, a reminder in case you missed it: For those of you in the New York City area: I’ll be joined by the wonderfully talented singer-songwriter-pianist Andrea Wittgens in giving a physics/music joint performance/presentation at the storied Cornelia Street Cafe, Sunday May 13th at 6 p.m., as part of their Entertaining Science series.  It’s entitled Rhapsody for Piano and Universe, and intended for the general public.  The place is pretty small, so get reservations in advance by calling 212.989.9319.

One more heads-up: again in NYC, June 16th, I’ll be giving a lecture:

THE EINSTEIN OBSESSION: SCIENCE, MYTH AND PUBLIC PERCEPTION

June 16th, 2pm

Jefferson Market Library, 425 6th Ave. West Village, NYC

Free and open to the public!

Who hasn’t heard of Einstein? We all know Einstein failed eighth grade math. (Although he didn’t.)  We know he showed energy is the same thing as mass (or was it “matter”?), that he’s the father of the atomic bomb, that he was an old man with frizzy hair, and that he was a patent clerk whose theory was that everything is relative and that nothing can move faster than light.  This messy assortment of half-truths and misconceptions permeates our culture and affects public perceptions of science, at many different levels.  In this talk we’ll consider how our culture’s obsession with Einstein impacts efforts to convey science to the public.

The reason this is possible has everything to do with Einstein’s special relativity, and the way mass and energy are intertwined there.  A crucial role is played by the energy that is most important for binding things together, which I’ve called “interaction energy”.

I’ve now written an article explaining why neutrons inside of nuclei can be stable, giving the example of the deuteron (one proton bound to one neutron) which is the nucleus of “heavy hydrogen”, or “deuterium”.  If you understand this example, you’ll basically understand the point for other nuclei as well.

[For those of you in the New York City area: I'll be joined by the wonderfully talented singer-songwriter-pianist Andrea Wittgens in giving a physics/music joint performance/presentation at the storied Cornelia Street Cafe, Sunday May 13th at 6 p.m., as part of their Entertaining Science series.  It's entitled Rhapsody for Piano and Universe, and intended for the general public.  The place is pretty small, so get reservations in advance.]

The workshop concluded with a panel discussion — the only point during the entire workshop when theorists were formally asked to say something. The panel consisted of Michael Peskin (senior statesman [and my Ph.D. advisor] famous for many reasons, including fundamental work on the implications of highly precise measurements ), Nima Arkani-Hamed (junior statesman, and famous for helping develop several revolutionary new ways of approaching the hierarchy problem),  Riccardo Rattazzi (also famous for conceptual advances in dealing with the hierarchy problem), Gavin Salam (famous for his work advancing the applications of the theory of quarks and gluons, including revolutionary methods for dealing with jets), and myself (famous for talking too much… though come to think of it, that was true of the whole panel, except Gavin.) And Raman Sundrum, one of the organizers (and famous for his collaboration with Lisa Randall in introducing “warped” extra dimensions, and also anomaly-mediated supersymmetry breaking [which was competitive with a paper by Rattazzi and his colleagues]) informally participated too.

What I like most about this discussion is that it captures a historic moment, as we are still mulling over the field-altering implications of the 2011 LHC data, but before we have enough data to really figure out what it’s telling us.  It is interesting to see where the panelists largely agree with one another and where they don’t. And it will be fascinating to look back at this video even as soon as a year from now; the same panel, if it were to be held in March 2013, would surely have very different things to say.  Maybe when we get there I’ll ask the panelists to write about how their views have changed over the year.

I feel I should say something about the fact that all the members of this panel are male. You should not conclude that the leading figures in the field are all male. Certainly if Lisa Randall [Harvard University] or Ann Nelson [University of Washington], two of the greatest theoretical particle physicists working today (and with whom I was fortunate to write papers in the 90s), had attended this conference, I am sure they would have been sitting on this panel, in place of less eminent panelists (me, for instance).

Now on to the video:

Left to right (from the viewer’s point of view):

• Raman Sundrum [University of Maryland], (initially standing and speaking off camera),
• Michael Peskin [SLAC and Stanford University],
• Nima Arkani-Hamed [Institute for Advanced Study],
• Gavin Salam [CERN (the LHC lab), Paris and Princeton],
• Me [Rutgers University],
• Riccardo Rattazzi [Ecole Polytechnique Federale de Lausanne]

Questions are asked off-camera by professor Patrick Meade of the State University of New York at Stonybrook.  (Meade, Sundrum and Michele Papucci of Berkeley organized the workshop.)

If you’re a particle physicist, you’ll have no trouble following the panel, but for those of you who aren’t, I’m afraid this is a high-level discussion which often lapses into jargon (see the limited glossary below). And it can get a little slow, so I think it unlikely that many non-experts will want to listen to the whole thing. So let me give you a few pointers (in both senses of the word).

• The discussion is 1 hour 23 minutes long.
• There are about two minutes of intro. Then from about 3:25 to 4:07 there’s a technical glitch which they didn’t edit out; skip til the video returns.
• From there, Professor Peskin presents his Four Slogans for 2012, which I described in an earlier post; now you can see them for yourself, though the language is quite technical.

Then the questions start (times listed):

• What would you personally most like the experimentalists at ATLAS and CMS [the two general-purpose experiments at the LHC] to look for in 2012? (0:09:00 – 0:30:00) [fairly technical answers]
• Do you think the excess seen at around a mass of 125 GeV/c² in the search for the Standard Model Higgs particle is really a Higgs? (0:30:00 – 0:35:00) [less technical; this regards the hints in the data that I have written about here, here and here.]
• Where do you think supersymmetry stands right now, given that no sign of superpartner particles were seen in 2011, and given that there might be a Standard-Model-like Higgs at 125 GeV/c²?(0:35:00 – 1:05:00) [fairly technical; see the articles linked from this one for relevant background information, and this article for my detailed answer to this question.]
• What is the one experimental result that would give you the most insight into BSM (see glossary below) physics? (1:05:00-1:11:00) [fairly technical]
• What do you see as the role of theorists who think about BSM physics going into the coming year(s)? (1:14:00-end) [less technical]

At a minimum I recommend non-experts listen to a little of what the brilliant, entertaining, and famously long-winded Nima Arkani-Hamed, of the Institute for Advanced Study, has to say; he’s larger than life and a lot of fun to watch. He waxes poetic a few times, and in some cases reviews moments in scientific history in an interesting way; see examples at 0:14:45, 0:40:00 [over ten minutes!], 1:14:55.

If you are curious about my own views, I suggest 0:20:00 (Higgs and 2012), 0:32:00 (is there a Higgs particle appearing in current data?) and 1:20:00 (more general philosophy about doing physics at the LHC).

Finally, a short glossary to help the non-experts, and even the younger grad students, through the jargon.

• “QCD” = Quantum ChromoDynamics, the highly-developed theory of quark and gluons whose equations are crucial for predicting anything and everything at the LHC
• “BSM” = Beyond-the-Standard-Model (i.e. something from new particles and/or forces)
• “RS” = Randall-Sundrum version of extra-dimensions ideas.
• “hierarchy problem”; click here for an explanation.
• “theoretical prior” = strong expectation based on a combination of past experiments and the current theoretical framework of quantum field theory
• “SUSY” = supersymmetry
• “stop”= top squark, “sbottom” = bottom squark — superpartner particles of the top and bottom quarks
• “gluino” = superpartner particle of the gluon
• “flavor” = relating to the various types of quarks, charged leptons and neutrinos, mainly regarding their masses and their decay modes
• “WIMP” = Weakly-Interacting Massive Particle (i.e. a particle that feels the weak nuclear force) that might or might not make up the dark matter of the universe

• sequential z prime, – a heavy version of a Z particle
• vector like single top quark – a heavy version of a top quark, see http://profmattstrassler.com/2012/02/02/lhc-as-juggernaut-and-behemoth/
• TDR – technical design report for an experiment
• b tags – see http://profmattstrassler.com/articles-and-posts/particle-physics-basics/the-known-apparently-elementary-particles/jets-the-manifestation-of-quarks-and-gluons/b-tagging-identifying-jets-from-bottom-quarks/
• Rpp decay = RPV decay = R-Parity-Violating decay = violation of assumption 1 in http://profmattstrassler.com/articles-and-posts/some-speculative-theoretical-ideas-for-the-lhc/supersymmetry/how-to-look-for-supersymmetry-at-the-lhc/
• maximally natural solution to heirachy problem = see http://profmattstrassler.com/articles-and-posts/particle-physics-basics/the-hierarchy-problem/ first, then a natural solution is a theory that accomodates the hierarchy readily, for many possible values of its parameters, i.e. without the need to adjust the parameters of the theory to very precise values.
• long lived colour particles (color –> colored) = a heavy quark-like particle that lives much longer than a trillionth of a second and may travel some distance through (or all the way through) the ATLAS or CMS detectors before it decays
• relic abundance of DM = how much dark matter is left over after the Big Bang
• sigma term(time) branching ratio = sigma times branching ratio = production rate times the probability for a certain type of decay.
• natural theory at weak scale = see “natural solution to hierarchy problem” above; “weak scale” is around 1 TeV, meaning accessible to the LHC
• t/tbar/MET = top quark + top antiquark + missing tranverse momentum, as would arise from producing a top squark and antisquark pair, where the top squark decays to a top quark and an undetectable particle, and the top antisquark decays to a top antiquark and an undetectable particle
• sleuth type approaches = technique for simultaneously looking at all the data for deviations from predictions; sounds great but very dificult to carry out in practise
• top prime, bottom prime = heavy versions of a top quark and bottom quark
• natural v’s unnatural = the issue is whether a theory’s parameters must be precisely adjusted in order to get physics similar to our world (unnatural) or whether a wide range of parameters will typically lead to physics similar to our world (natural)
• 5/3 charge particles = just what it sounds like: particles with charge 5/3 times larger than that of a proton (compare with a top quark that has charge 2/3
• top squark = moderately likely (but by no means certain) to be the first superparticle discovered, IF supersymmetry exists of course!

http://www.mica-vw.org/wiki/index.php/A_Ring_Of_Truth_-_Seeking_Answers_to_Big_Questions_at_the_Large_Hadron_Collider

And I recommend you take a look at their other talks also; it’s a great list.

http://www.mica-vw.org/wiki/index.php/Popular_Talks

What is MICA?  Here’s what they say at their website.

Meta Institute for Computational Astrophysics

• The Meta Institute for Computational Astrophysics (MICA) is a professional scientific and educational, non-profit organization based in virtual worlds [VWs]. We are currently using Second Life (SL), and the Intel’s OpenSim-based world ScienceSim, and may expand to other venues as the VWs evolve.

Overall, this is not a bad article — but that last bit is propaganda.  Maybe physicists made a nano-step (“nano” = one billionth).  We knew this particle — a composite object made from known particles — would be there; we just didn’t know its details.  To suggest this is a step toward a breakthrough is just silliness.  Of course all new information proves useful eventually for something, but… really!

And the first part?  Less exciting than it sounds (though a very nice bit of research!)  Here’s the link to my post about this from Friday, explaining that the CMS experiment at the Large Hadron Collider has reported very strong evidence for a new composite object — a hadron, a member of a particular subclass called a `baryon’ —  made from a single bottom (or `beauty’ — or just `b’) quark and from other known particles.

The reporter tells the usual white lie:

Baryons are particles made of three quarks (the building blocks of the protons and neutrons that populate the nuclei of atoms). Beauty baryons are baryons that contain at least one beauty quark (also known as a bottom quark). The new specimen is a particular type of excited beauty baryon called Xi(b)*, pronounced “csai-bee-star.”

A better description of baryons (including protons) is that they are made from three quarks, many gluons, and many additional pairs of quarks and anti-quarks.  The three excess quarks are the ones being referred to in the above paragraph.  See my article on what protons are and Friday’s post on this new one, which shows a sketch that gives better intuition about what protons and Xi(b)*s look like.

[Sometimes white lies get you into a lot of trouble later.  The fact that protons have gluons and anti-quarks in them is crucial to understanding how the Large Hadron Collider does its thing.]

The reporter gets this part right:

The Xi(b)* particle had been predicted by a physics theory called quantum chromodynamics, which predicts how quarks bind together to form heavy particles, but had never before been observed.

“It was expected to be more or less where it was found,” [Vincenzo] Chiochia said. “Not all of those heavy states have been discovered, so you have to look for all those particles. It may well be that the theory is not complete. In this particular case it was expected, but we have to keep looking for things that are unexpected.”

Well.  I don’t know about that, Dr. Chiochia.  As a quantum field theorist, I would agree that “quantum chromodynamics” (which does more than what the reporter writes — it is the set of equations that describes and predicts all of the interactions of quarks, gluons and anti-quarks of all types) might indeed be turn out to be incomplete.  But if you really want to look for places where it might fail, this is an especially bad place to look!  This composite particle itself may be new, but the forces and particles required to make this object have already been very well-studied in other contexts.  (Nevertheless, congratulations on nice work!)

Oh, and by the way, Wind Farms Do Not Cause Global Warming.  They may cause some local mixing of warmer air just above the ground at night down to the surface near the wind farm itself; this does not increase the overall temperature of the planet.  Read headlines (and articles) very carefully.  http://www.washingtonpost.com/blogs/ezra-klein/post/no-wind-farms-are-not-causing-global-warming/2012/04/30/gIQAMl2GsT_blog.html

I’ve been wanting to address this for a while, because many of you have asked penetrating and central questions about the basic structure of matter, such as:

• Why is the neutron stable inside of atomic nuclei, given that on its own it is unstable?
• Why is the proton arguably heavier than the quarks and gluons that make it up?

And there are other equally important questions that no readers have yet stumbled upon but that I ought to address.  Before I can answer any of those questions, however, I have to first describe interaction energy and the role that it plays in structure.

So — without further ado, here’s the article.  This was an especially hard article to write and it may well be confusing in places — so I very much welcome your feedback, in order that I can try to make it clearer, if necessary, in later versions.