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Moriond 08: Day 1 March 5, 2008

Posted by apetrov in Particle Physics, Physics, Science.
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So now that I finally twisted my knee and removed from skiing, I can report on that Moriond meeting. Most of the talks from the conference can be found here, and thus I’ll only briefly comment on the talks. The morning session was about Higgs searches and in general about electroweak symmetry breaking. Curiously enough, it was callled “LHC and Brout-Englert-Higgs Mechanism” (emphasis is mine — I wonder what happened to the names of G. Guralnik, C. R. Hagen, T. Kibble, P. Anderson and E. Stückelberg who also could lay claim on that mechanism…).

The first talk was, as usual, a welcome by the conference founder Jean Tran Thanh Van – although he told me later that he wants to retire form this post and this would be his last conference. This conference is, and alwys has been, organized impeccably, so I hope this tradition will be kept. The first two talks dealt with Higgs boson searches at the Tevatron in the low mass (< 140 GeV) and high mass regions (> 140 GeV), and also non-SM Higgs (Yorita, Zivovic and Haas). This curious separation is due to the fact that search techniques are very different for those mass ranges, which has to do with WW threshold. As you could guess, no discovery yet… but it was emphasized that Fermilab’s HighRise looks like an “H” which might stand for Higgs, so maybe they’d beat LHC to it… One nice thing about the analyses was that the results were presented as plots of Higgs mass vs Higgs production cross-section. This is nice, as if it is discovered, we’d know if its couplings are given by the Standard Model or not… Michel Tytgat gave a nice talk about a very cute model of Dark Matter which is jsut a neutral Higgs of some limit of two-Higgs model (“Inert Higgs”), which is a nice way to connect the two. Gustavo Burdman gave a review of holographic way of electroweak symmetry breaking. Lyn Evans gave a talk about LHC commissioning schedule (Jester wrote about that in his blog, so I’m not going to go into that) and D. Aguila talked about how LHC can help with tests of see-saw mechanism of neutrino mass generation.

The conference continued after the ski break with talks about SM physics at the Tevatron, HERA, and (in the future) LHC — talks by Han, Han, de Boer, Christiansen, Plamodon) and searches for new physics with photons and jets by Jaffre. A nice talk about Higgs as an inflaton was given by Fedor Bezrukov, which is a nice attempt to unify Higgs and the inflaton (field that drives inflation on the early Universe) by introducing non-minimal gravitational couplings for that scalar. The model that he described requires some careful choice of couplings to make sure early Universe develops properly, which almost drives him in the strong coupling limit. Also, higher-dimensional operators can be problematic… but the model is indeed cute! The session ended with a pedagogical talk from S. Kraml about SUSY Dark Matter.

I ‘ll try to update regularly from now on, but the Internet here is only available at the bar and you can gues how much work can be done at the bar….

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Comments»

1. Photo[shop] of the day: Fermilab “Higgs” building « An American Physics Student in England - March 6, 2008

[…] Petrov mentioned a similar image, so I’ll assume that this has become standard Fermilab/CDF/D0 outreach material. Filed […]

2. Chris - April 8, 2008

There seems to be a concerted effort by UK and EU countries to try to ignore that Hagen, Kibble, and Guralnik have the same claim and better paper than Brout-Englert-Higgs. Additionally, no one calls it the Brout-Englert-Higgs so not sure why the physics community it letting that happen. Higgs is clearly is not the best physicist of this bunch but his name is attached to it and that is now part of the Higgs lore. But the Belgium guys have no cliam higher than the Hagen, Kibble, and Guralnik team. Thanks for making this point on your site.

3. Chris - April 8, 2008

Above should say…There seems to be a concerted effort by UK and EU countries to try to ignore that Hagen, Kibble, and Guralnik have the same claim and better paper than [Brout and Englert or Higgs].

Sorry about that.

4. Moriond 2008: the rest of the conference « Symmetry factor - April 16, 2008

[…] to update my blog. There are many things to talk about. But first, I have to finish blogging about that conference that happened more than a month ago. So here it […]

5. Larry - June 24, 2009

The Europeans are pretty sneaky in trying getting the Nobel math to work at 3. There are differences in these papers that back in 1964 were more significant and the Nobel Committee must be considering – regardless of the influencing by t’Hooft, Velrtman, Borut, Englert and others.

http://www.symmetrymagazine.org/breaking/2008/05/16/the-jpsi-particle-original-papers

>>>>>>>>>>>>>from the above link>>>>>>>>>

Both PH and EB worked in the Lorentz (i.e., manifestly covariant) gauge. Thus the Goldstone theorem would be fully expected to apply. However, PH is also done purely classically (i.e., without quantum theory), which means that the Goldstone theorem (a result from QUANTUM field theory) really has no obvious application. What PH does is to show that with a broken symmetry condition the classical field equations can be juggled into the form of the equations of a MASSIVE vector boson. Namely, the broken symmetry condition gives mass. That is a good thing, but what of the radiation gauge avoidance of the Goldstone theorem which PH had touted in his earlier paper? Is it not strange that that avoidance mechanism is not mentioned in the PH paper?

EB do some calculations in quantum field theory in which they impose a broken symmetry condition. Given the fact that a broken symmetry condition introduces a mass parameter into the theory it is not surprising that they also find a MASSIVE vector boson. But what of the zero mass particle which they must have according to the Goldstone theorem? They need to show that there is a decoupling of that particle from the physical sectors of the theory. In other words, it needs to show the zero mass particle is purely a so-called gauge excitation. That is in fact the case, but is not shown in EB.

GHK uses the radiation gauge and shows that a massive vector particle emerges from a broken symmetry condition. Thus GHK achieves the goal of lending mass to the vector particle, but is not plagued by the encumbrance of the Goldstone theorem. Moreover, GHK shows explicitly the precise way in which the Goldstone theorem fails in the context of their model.

One can thus sum up by saying that in a sense PH and EB solved half of the problem – namely massifying the gauge particle. GHK really solved an entire problem – massifying and also showing how the deadening hand of the Goldstone theorem is avoided.

6. Larry - July 27, 2009

As a follow-up to this blog, I would love to see a blog on this paper – or get your perspective

Anyone who has an interest in the mass boson, LHC, Fermi, and physics history will find it a great read and probably agree that it is the one of the most definitive histories on the Higgs boson theory discovery.

If you want to know what theoretical physics was like back in the 60’s it also discussed that and the key players at those locations in Cambridge, London, and Rochester. Most importantly, it tells the story of the mass boson through the eyes of GHK and the merits of the three papers that were credited (and recognized as milestone papers this year by PRL’s 50th anniversary) for the mass boson discovery back in 1964. The paper will most likely tick off a few Europeans but it is the first honest assessment of the three papers that have been written.

http://arxiv.org/abs/0907.3466
http://lanl.arxiv.org/PS_cache/arxiv/pdf/0907/0907.3466v1.pdf

The paper was published in a recent issue of International Journal of Modern Physics A (IJMPA). Volume: 24, Issue: 14 (2009) pp. 2601-2627

http://www.worldscinet.com/ijmpa/24/2414/S0217751X09045431.html

Look forward to your thoughts.

7. Time is it moving slower than it was in the young universe? - October 14, 2009

[…] is the spontaneous symmetry breaking that produces the Higgs Field. WMAP Inflation Theory Moriond 08: Day 1 Symmetry factor […]

8. physicspet - March 2, 2010

Sakurai Award and Talks were posted on YouTube.

http://www.youtube.com/view_play_list?p=BDA16F52CA3C9B1D

Enjoy.

9. Bill Rankins - April 24, 2011

I simply could not leave your site prior to suggesting that I really enjoyed the usual information a person supply on your visitors? Is gonna be again ceaselessly in order to check up on new posts


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