Log In

Register Now

Help

Home Page

Today's Paper

Video

Most Popular

Times Topics

Search All NYTimes.com

Science

World

U.S.

N.Y. / Region

Business

Technology

Science

Environment

Space & Cosmos

Health

Sports

Opinion

Arts

Style

Travel

Jobs

Real Estate

Autos

Two Technical Problems Leave Neutrinos’ Speed in Question

By KENNETH CHANG

Published: February 23, 2012

Sign In to E-Mail

Print

Reprints

Remember those faster-than-light neutrinos that supposedly defied Einstein’s speed limit?

RSS Feed

Get Science News From The New York Times »

Never mind — or rather, maybe.

Last September, CERN, the European Organization for Nuclear Research, based outside Geneva, announced a finding that, if true, would throw a large monkey wrench into physics as we know it. Ghostly subatomic particles known as neutrinos that were generated at CERN and beamed through the earth 453 miles to a detector in Italy appeared to be arriving at their destination about 60 billionths of a second faster than a particle of light would.

In a detailed scrutiny of the experiment, CERN, which runs a particle-smashing machine called the Large Hadron Collider, found two problems with its equipment that could have affected its measurements.

One is an electronic component that marked the exact times for GPS measurements. (The experiment requires such precise measurements of time and distance that even continental drift is taken into account.) The component was “clearly out of its specifications,” said Dario Autiero, a physicist who is the spokesman for the experiment.

However, that error would have sped up the neutrinos even more.

The second potential error is in the fiber-optic cabling that carried the GPS data five miles to the underground detector. The investigation discovered that for dimmer light pulses, the circuit receiving the data introduced delay — up to 60 billionths of a second — that could bring the neutrinos’ speed back under the speed of light. The circuit has now been fixed.

The journal Science reported the potential fraying of the experiment’s conclusions — which many physicists had found hard to believe in the first place — on its Web site on Wednesday.

But Dr. Autiero said the issues it identified did not conclusively prove or disprove the findings. “We are not sure of the state of this connection in the past,” he said.

A new round of neutrino firings will begin in late March, and if the cable issue is at fault, the answer will be resolved shortly afterward.

Get Free E-mail Alerts on These Topics

Neutrinos | Physics
CERN

Advertise on NYTimes.com

His and hers houses

Also in Style »

Do these two looks mix well?

Perry Ellis still has something to say

Advertisements

Confronting the Scars of Battle

Inside NYTimes.com

Education Life »

Molding a New Med Student

N.Y. / Region »

Making Education Brain Science

Sunday Review »

The Strip: Social Media Start-Ups

Fashion & Style »

Weddings and Celebrations

Sunday Review »

Opinion: Why Medical Bills Are a Mystery

Until we figure out the true costs of delivering health care to patients, we can’t make the system more efficient.

Magazine »

Robert Caro’s Big Dig

T Magazine »

T Summer Women’s Fashion

Sunday Review »

Opinion: ‘Hunger Games’ Parenting

Arts »

Out of Adversity, Visions of Life

Travel »

Off the Coast of Spain, a Tranquil Biosphere

Sunday Review »

Opinion: Lefties Aren’t Special After All

The tendency to associate left-handedness with creativity is unfounded.

Movies »

A Film’s Superheroes Include the Director

Home

World

U.S.

N.Y. / Region

Business

Technology

Science

Health

Sports

Opinion

Arts

Style

Travel

Jobs

Real Estate

Autos

Site Map

© 2012 The New York Times Company

Privacy

Your Ad Choices

Terms of Service

Terms of Sale

Corrections

RSS

Help

Contact Us

Work for Us

Advertise