Thursday, June 20, 2013 ... /////

Supersymmetric Google Hangout with John Ellis

According to a 2004 SPIRES survey, the CERN particle phenomenologist John Ellis of the U.K. was the second most cited physicist in high-energy physics and, except for the third one (Steven Weinberg), the only one surpassing 50% of the citations collected by Edward Witten. ;-)

After 2004, he actually added over 170 papers with 6,000+ new citations, which, along with the new citations earned by the older papers, brought him from 33,000+ to 53,000+ now. At least in the discipline of citation collection, you should definitely not forget about John Ellis! You may also know John Ellis as a maverick who dared to disagree with the great high school teacher Walter Wagner who had calculated that the LHC would devour the Earth. Also, his CERN introduction to the Higgs field earned over half a million of views.

Most of his research has gone well beyond the Lagrangian terms on his T-shirt on the image elsewhere in this text; in other words, he's been primarily researching Beyond the Standard Model physics. Today, you may ask a question – or at least a question about supersymmetry – to him.

Incidentally, the first tetraquark (a pair of mesons stuck together) called $Z_c(3900)$ was discovered by Japan's Belle Experiment as well as Beijing EPC a few days ago, see e.g. Nature.

snail feedback (8) :

That is not a tetraquark your naive guy ;-), data is still inconclusive (read the paper!) for such bold assertions ... anyway, if you believe in the real theory of nuclear interactions, which forbids by ab initio calculations such kind of boundstates, you would have no doubt what they really are!

I didn't write that a particular paper says that it's a tetraquark. I wrote that it *is* a tetraquark. For some reasons why I am ready to bet on this, see e.g.

http://arxiv.org/abs/1304.6433

Let me mention that tetraquarks and pentaquarks are different objects and the existence of one doesn't imply the existence of the other, and vice versa.

A TRF text related to pentaquarks:

http://motls.blogspot.com/2005/10/pentaquarks.html?m=1

In the hangout video, John is looking more and more like Gandalf :)

Dear "Check Author", once you are clearly better in linguistics (or collecting typos) than in physics please re-check your sources because by providing us with tons of model-dependent hep-ph papers is no real counterargument against (lack of tetraquark in) lattice data. The Nature's article is clear when it states that the "tetraquark" hypothesis is still too debated to be considered a 5-sigma discovery. To know: "But the experiments’ margin of error is still too great to rule out the possibility of molecular mesons breaking down". Most likely the these poor guys in Belle are, as many others in recent history, just being confused by another typical QCD resonance. How much do you bet?

Thanks Lubos. Yes. I should have made clear. My remarks were based in part on a 2003 (yes a decade ago) link regards pentaquark saying the Belle group has also discovered tetraquark