The tantalizing possibility that neutrinos were measured traveling faster than light was big news last September, told here in “Light Finishes Second” –
[CERN physicists] beamed muon neutrinos from an accelerator at CERN outside Geneva to a detector at the Gran Sasso National Laboratory in Italy, about 450 miles away, to see how many showed up as a different type, tau neutrinos. Neutrinos come in a number of types, and have recently been seen to switch spontaneously from one type to another. The neutrinos in the experiment were detected arriving 60 nanoseconds sooner than if they’d been traveling at lightspeed.
Now Science magazine’s website is blaming the result on a bad connection in a fiber optic cable connecting a GPS receiver (used to correct the timing of the neutrinos’ flight) and a computer.
Jerry Pournelle answered the latest findings on Chaos Manor with this comment:
The applicable Pournelle’s Law was one of troubleshooting: 90% of the time it’s a cable. I first formulated that back in S-100 days, and it’s still true. Now it may be that we’re better off without faster than light neutrons, but I for one regret that they’re going away. Of course this was always the way to bet it, but it was a more intereresting universe when everything we thought we understood was fundamentally wrong…
I applaud that attitude in a hard science fiction writer. And it seems CERN’s scientists themselves may not be finished with the question. CERN’s OPERA team, the group doing these experiments, say the faulty cable could have led to an undercalculation instead, meaning the neutrinos may have exceeded lightspeed by an even greater margin than previously suggested:
“The optical fiber connector … brings the external GPS signal to the OPERA master clock,” explained the science lab, and it “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.”
On the other hand, another equipment issue under review may restore the mundane universe to status quo ante:
A second issue with the study involves an oscillator used to provide the time stamps for the GPS synchronization. Flaws with that gadget may have led to an overestimate of speeds — keeping neutrinos in line with Einstein’s theories.
[Via Chronicles of the Dawn Patrol.]
Light, don’t look back — something may be gaining on you.
A team of experimental physicists at CERN say they have measured neutrinos traveling faster than the speed of light.
They beamed muon neutrinos from an accelerator at CERN outside Geneva to a detector at the Gran Sasso National Laboratory in Italy, about 450 miles away, to see how many showed up as a different type, tau neutrinos. Neutrinos come in a number of types, and have recently been seen to switch spontaneously from one type to another.
The neutrinos in the experiment were detected arriving 60 nanoseconds sooner than if they’d been traveling at lightspeed.
Were they wind-assisted? Should they be tested for steroids? Well, it’s no laughing matter to scientists who depend on Einstein’s Special Theory of Relativity to explain their other observations.
And this didn’t happen only once. The physicists, working on the OPERA collaboration, measured the travel times of neutrino bunches some 15,000 times, a level of statistical significance that in scientific circles would count as a formal discovery.
Stephen Parke, a theoretical particle physicist at Fermilab in Batavia, IL, suggests the findings will be explained without invalidating special relativity:
It’s possible the neutrinos’ passage hadn’t been timed accurately. Or maybe the neutrinos were traveling through different dimensions, taking shortcuts from Geneva to Gran Sasso.
Shortcuts through other dimensions? Is that a quote from Doctor Parke or Doctor Who?
Providing an anticlimactic fizzle to its controversial launch, CERN’s Large Hadron Collider has proven dangerous only to itself. Operations have twice been interrupted by mechnical problems, and the latest will take months to repair.
The world’s largest particle collider malfunctioned within hours of its launch, but the media was led to believe there had been a successful startup and CERN did not admit the truth until September 18, after the Associated Press called asking about rumors of trouble.
In a statement Thursday, the European Organization for Nuclear Research reported for the first time that a 30-ton transformer that cools part of the collider broke, forcing physicists to stop using the atom smasher just a day after starting it up last week.
Then the day after that revelation, September 19, the LHC administered itself the coup de grace, suffering a major failure. The CERN press release explains:
During commissioning (without beam) of the final LHC sector (sector 34) at high current for operation at 5 TeV, an incident occurred at mid-day on Friday 19 September resulting in a large helium leak into the tunnel. Preliminary investigations indicate that the most likely cause of the problem was a faulty electrical connection between two magnets, which probably melted at high current leading to mechanical failure. CERN’s strict safety regulations ensured that at no time was there any risk to people.
A full investigation is underway, but it is already clear that the sector will have to be warmed up for repairs to take place. This implies a minimum of two months down time for LHC operation. For the same fault, not uncommon in a normally conducting machine, the repair time would be a matter of days.
Follow LHC’s cooldown status at the official site.
Update 9/23/2008: CNN reports that repairs to the LHC will keep it inactive until next spring.
“World ends, film at eleven!” Look for that promo Wednesday night if the critics’ frightening predictions come true when CERN starts the first injection of a beam through the Large Hadron Collider a few hours from now, at 9:30 Central European Time.
The Geneva-based particle physics laboratory has stressed in a peer-reviewed report the soundness and safety of the project. But the media’s morbid fascination with the possibility of – almost a longing for – a disaster has prompted one service to offer live video of the LHC startup, while CERN has promised journalists satellite uplink will be provided throughout the day by Eurovision.
But when it comes to discussing the Large Hadron Collider, quite in contrast to other scientific controversies of the day, say, global warming, the left and right wings of the sf community are surprisingly in agreement that there’s little reason to get in an uproar.
Cheryl Morgan scoffed at “A Nation of Doomsayers” while pointing out The Guardian’s silly opinion poll that poses two extreme choices: “Are you worried the atom smasher will unwittingly destroy the planet or is that scientifically illiterate, millenarian twaddle – which is it to be?”
Similarly, Jerry Pournelle showed how unworried he is by ironically commenting:
Well, according to a German chemist it won’t matter since they will create a Quasar in the center of the Earth, and in a few years we’ll see light beams coming out of the oceans, after which we are all doomed.
The most reassuring prediction I’ve found about the imminent startup of LHC was Stephen Hawking’s $100 bet with Professor Gordy Kane, of Michigan University, over the existence of the Higgs boson. Not because Hawking might win, but because he clearly expects to be around to settle the bet.