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Geometric Unity: phenomenal advance, or crazy theory?

By Peter Rowlett. Posted May 25, 2013

Marcus du Sautoy has this week presented to the world the physics of Eric Weinstein. ‘Geometric Unity’, apparently, argues “that the seemingly baroque features of the standard model of particle physics are in fact inexorable and geometrically natural when generalizations of the Yang-Mills and Dirac theories are unified with one of general relativity”.

Apparently, du Sautoy and Weinstein were postdocs together in the 1990s. Weinstein is a mathematical physicist turned economist who has been working on his these ideas privately for 20 years. Two years ago, he started to explain his thoughts to Marcus in a bar in New York.

Higgs boson discovery passes peer review

By Peter Rowlett. Posted September 16, 2012

The discovery of the Higgs boson, which “completes the standard model [of particle physics]” according to New Scientist, has passed peer review. Two papers, from the two experiments which each contributed to the discovery, have been published in Volume 716, Issue 1 (17 September 2012) of Physics Letters B, the same journal as Peter Higgs’ original paper which proposed the existence of a “mass-giving boson”. Despite declaring the standard model complete, the New Scientist piece says it is “lacking” and welcomes “the hunt for new physics”. Both papers are “Universally Available” at Science Direct (links below).

Source: Higgs boson gets peer-review seal of approval (New Scientist).

Papers:
Observation of a new particle in the search for the Standard Model Higgs boson with the ATLAS detector at the LHC (ATLAS Collaboration, 2012, Physics Letters B, 1-29);
Observation of a new boson at a mass of 125 GeV with the CMS experiment at the LHC (CMS Collaboration, 2012, Physics Letters B, 30-61).

Have they discovered the Higgs boson? Probably

By Peter Rowlett. Posted July 4, 2012

I feel that we should acknowledge the announcement made at CERN this morning. As put by Brian Cox on Twitter: “ATLAS and CMS have independently discovered a new particle mass ~ 126 GeV which behaves like [the standard model] Higgs”. This is all based on statistical analysis of experimental data and, since the Higgs cannot be observed directly, there are some outstanding questions that require further research.

Have they discovered the Higgs boson? The answer is: probably. If it’s the Higgs, then it’s a nice example of theoretical physics making demonstrable predictions about nature. If the discovered particle is something else, then there’s a bunch more theoretical work to do to understand this.

Two possible errors in FTL neutrino result

By Peter Rowlett. Posted February 25, 2012

The OPERA project has identified two possible sources of error in the experiment that appeared to observe neutrinos travelling faster than the speed of light. The CERN press release reads:

The OPERA collaboration has informed its funding agencies and host laboratories that it has identified two possible effects that could have an influence on its neutrino timing measurement. These both require further tests with a short pulsed beam. If confirmed, one would increase the size of the measured effect, the other would diminish it. The first possible effect concerns an oscillator used to provide the time stamps for GPS synchronizations. It could have led to an overestimate of the neutrino’s time of flight. The second concerns the optical fibre connector that brings the external GPS signal to the OPERA master clock, which may not have been functioning correctly when the measurements were taken. If this is the case, it could have led to an underestimate of the time of flight of the neutrinos. The potential extent of these two effects is being studied by the OPERA collaboration. New measurements with short pulsed beams are scheduled for May.

Source: OPERA experiment reports anomaly in flight time of neutrinos from CERN to Gran Sasso: UPDATE 23 February 2012.