Recommended by us: Time to move on?

''Cosmology and particle physics have long been dominated by theoretical paradigms: Einstein's general theory of relativity in cosmology and the Standard Model of particle physics. The time may have come for paradigm shifts. Does cosmological inflation require a modification of Einstein's gravity? Have experiments at the LHC discovered a new particle beyond the Standard Model? It is premature to answer these questions, but we theorists can dream about the possibilities.''
 

Full conference proceeding  here.

Quote of the day: A lost Generation?

" It is easy to estimate the total number of active high-energy theorists. Every day hep-th and hep-ph bring us about thirty new papers. Assuming that on average an active theorist publishes 3-4 papers per year, we get 2500 to 3000 theorists. The majority of them are young theorists in their thirties or early forties. During their careers many of them never worked on any issues beyond supersymmetry-based phenomenology or string theory. Given the crises (or, at least, huge question marks) in these two areas we currently face, there seems to be a serious problem in the community. Usually such times of uncertainty as to the direction of future research offer wide opportunities to young people, in the prime of their careers. To grab these opportunities a certain reorientation and reeducation are apparently needed. Will this happen?" (M. Shifman).

From the paper arXiv:1211.0004v3:
"Reflections and Impressionistic Portrait at the Conference Frontiers Beyond the Standard Model", FTPI, Oct. 2012
M. Shifman, William I. Fine Theoretical Physics Institute, University of Minnesota.

Recommended by us: gravitons

“  Gravitons Sesame Street has a learning game that goes with the jingle "One of these things is not like the other. One of these things just doesn't belong." Can you find which one is different? If you've read anything about the kinds of physics we do at Fermilab, you've heard lots of words ending with "on" – words like proton, neutron, gluon, photon, boson, fermion and on and on and on. One of the words you might have encountered is the graviton. Let's get one thing out of the way: At the moment, gravitons are entirely theoretical constructs that delicately walk the knife-edge precipice between the domains of scientific respectability and the shady world of hand waving. The fantastic success of quantum theory to describe three forces – electromagnetism and the strong and weak nuclear forces – provides a considerable impetus to try to marry it to the fourth force of gravity. In the same way that the photon is known to be the quantum particle of the electromagnetic force and the gluon is the quantum particle of the strong force, the "graviton" is the name given to a hypothetical quantum particle of the gravitational force. However, a quantum theory of gravity has so far been elusive. Einstein's theory of general relativity has been the most successful description of gravity, but when it encounters the quantum realm, it predicts nonsense, with impossible infinities popping up throughout the calculations. Infinities like that are nature's way of saying "back to the drawing board." And though theoretical physicists have quite a way to go in coming up with such a model, it is still possible to work out some of the properties of gravitons. (Continue to read on Fermilab Today)

                 ”

The hunt ended. Let's eat the prey.

The discovery of a "resonance" with a mass of ~125 GeV that may well be the Higgs boson, the missing piece in the Standard Model (SM) puzzle, has finally been announced by the ATLAS and CMS collaborations at CERN.
The (experimental) hunt started in 1989 at CERN with the Large Electron-Positron (LEP) collider and ended in the same place, but with the Large Hadron Collider (LHC), 23 years later.
For those of you interested in details, slides from the presentations given by representatives of the collaborations can be found at http://indico.cern.ch/conferenceDisplay.py?confId=197461

What follows may not be technically entirely correct but it is meant for people not working in particle physics to have an idea of how results are produced. Still a basic understanding of statistics is required.
For consistency, only results from ATLAS will be shown, however the reader must be aware that very similar plots have been released by CMS.

Neutrini, muoni e fattori g da non trascurare...

Il 25-26 Aprile si è tenuto un workshop della collaborazione del Fermilab (qui le slides) per la riconfigurazione dell’insieme dei rivelatori nella miniera di Homestake (miniera che ci è familiare dalla vicenda dei neutrini solari che ho descritto in un post precedente) dal nome LBNE (Long-Baseline Neutrino Experiment). In tempo di crisi economica mondiale lo scopo del workshop è stato più gestionale che altro, dal momento che i partecipanti hanno aiutato a valutare le migliori opzioni per fare buona scienza con la minor quantità di denaro.

Dalle parole del vicedirettore del Fermilab Young-Kee Kim, in riferimento agli esperimenti previsti, sembra che tutto proceda per il meglio:"We're in very good shape for the next 10 years, for neutrino and muon programs."