24小时热门版块排行榜

返回列表

当前只显示满足指定条件的回帖，点击这里查看本话题的所有回帖

coolrainbow

木虫 (著名写手)

未来国家冻凉

QC强帖: 11
应助: 1 (幼儿园)
贵宾: 0.1
金币: 3979.5
散金: 10
红花: 50
帖子: 1137
在线: 272.3小时
虫号: 239560
注册: 2006-04-07
性别: GG
专业: 理论和计算化学

[交流] 中微子超光速？爱因斯坦还是赢了：电脑上有根线没插好已有22人参与

http://news.sciencemag.org/scien ... -undoes-faster.html
BREAKING NEWS: Error Undoes Faster-Than-Light Neutrino Results
It appears that the faster-than-light neutrino results, announced last September by the OPERA collaboration in Italy, was due to a mistake after all. A bad connection between a GPS unit and a computer may be to blame.

Physicists had detected neutrinos travelling from the CERN laboratory in Geneva to the Gran Sasso laboratory near L'Aquila that appeared to make the trip in about 60 nanoseconds less than light speed. Many other physicists suspected that the result was due to some kind of error, given that it seems at odds with Einstein's special theory of relativity, which says nothing can travel faster than the speed of light. That theory has been vindicated by many experiments over the decades.

According to sources familiar with the experiment, the 60 nanoseconds discrepancy appears to come from a bad connection between a fiber optic cable that connects to the GPS receiver used to correct the timing of the neutrinos' flight and an electronic card in a computer. After tightening the connection and then measuring the time it takes data to travel the length of the fiber, researchers found that the data arrive 60 nanoseconds earlier than assumed. Since this time is subtracted from the overall time of flight, it appears to explain the early arrival of the neutrinos. New data, however, will be needed to confirm this hypothesis.

回复此楼

» 猜你喜欢

华南师范大学广州市光谱分析与功能探针重点实验室诚招青年英才和博士后岗位研究人员已经有11人回复
华南师范大学广州市光谱分析与功能探针重点实验室诚招青年英才和博士后岗位研究人员已经有10人回复
物理化学论文润色/翻译怎么收费? 已经有123人回复
PbS量子点如何确定浓度已经有11人回复
大湾区大学刘天辉课题组招收2026级博士生（与中山大学物理学院联合培养）已经有22人回复
PbS量子点紫外吸收已经有0人回复
求标准卡片Cu0.4In0.4Zn1.2S2 PDF#32-0340 已经有2人回复
比利时鲁汶大学与国家留学基金委共同资助博士研究生CSC-KU Leuven PhD Scholarship 已经有0人回复
量子点电致发光器件（QLED）：蓝光量子点（QDs）和纳米氧化锌电子传输材料已经有0人回复
七嗪类物质合成求助已经有0人回复
需要一个圆偏振光诱导化学反应，请问使用圆偏振光作为光源，应该需要哪些设备搭建已经有0人回复

» 本主题相关价值贴推荐，对您同样有帮助:

技术博客：http://hi.baidu.com/coolrainbow/blog

1楼2012-02-23 13:24:09

已阅回复此楼关注TA 给TA发消息送TA红花 TA的回帖

zhxd1028

禁虫 (小有名气)

★
小木虫(金币+0.5):给个红包，谢谢回帖

本帖内容被屏蔽

7楼2012-02-23 18:40:07

已阅回复此楼关注TA 给TA发消息送TA红花 TA的回帖

查看全部 31 个回答

coolrainbow

木虫 (著名写手)

未来国家冻凉

QC强帖: 11
应助: 1 (幼儿园)
贵宾: 0.1
金币: 3979.5
散金: 10
红花: 50
帖子: 1137
在线: 272.3小时
虫号: 239560
注册: 2006-04-07
性别: GG
专业: 理论和计算化学

Nature连接：
http://blogs.nature.com/news/201 ... ossible-errors.html

Faster-than-light neutrino measurement has two possible errors

22 Feb 2012 | 22:49 GMT | Posted by Eugenie Samuel Reich | Category: Physics & Mathematics

The OPERA collaboration, which made headlines in September with the revolutionary claim to have clocked neutrinos traveling faster than the speed of light, has identified two possible sources of error in its experiment. If true its result would have violated Einstein’s Special Theory of Relativity, a cornerstone of modern physics.

OPERA had collected data suggesting that neutrinos generated at CERN near Geneva and sent 730 kilometers to its detector Gran Sasso National Laboratory were arriving 60 nanoseconds faster than a light beam would take to travel the same distance. Many physicists were skeptical but the measurement appeared to be carefully done and reached a statistically significant level.

But according to a statement OPERA began circulating today, two possible problems have now been found with its set-up. As many physicists had speculated might be the case, both are related to the experiment’s pioneering use of Global Positioning System (GPS) signals to synchronize atomic clocks at each end of its neutrino beam. First, the passage of time on the clocks between the arrival of the synchronizing signal has to be interpolated and OPERA now says this may not have been done correctly. Second, there was a possible faulty connection between the GPS signal and the OPERA master clock.

An anonymously sourced account on Science Insider today broke the news that OPERA may have made a mistake . That report says the faulty connection can account exactly for the 60 nanosecond effect. OPERA’s official statement stops short of that, saying instead that its two possible sources of error point in opposite directions and it is still working things out. Its statement reads in full:

“The OPERA Collaboration, by continuing its campaign of verifications on the neutrino velocity measurement, has identified two issues that could significantly affect the reported result. The first one is linked to the oscillator used to produce the events time-stamps in between the GPS synchronizations. The second point is related to the connection of the optical fiber bringing the external GPS signal to the OPERA master clock.

These two issues can modify the neutrino time of flight in opposite directions. While continuing our investigations, in order to unambiguously quantify the effect on the observed result, the Collaboration is looking forward to performing a new measurement of the neutrino velocity as soon as a new bunched beam will be available in 2012. An extensive report on the above mentioned verifications and results will be shortly made available to the scientific committees and agencies.”

Caren Hagner, a member of OPERA at the University of Hamburg in Germany, says “For the moment the collaboration decided not to make a quantitative statement, because we have to recheck and discuss the findings more thoroughly.”

At Fermilab, members of the MINOS collaboration (Main Injector Neutrino Oscillation Search) continue to try to make their own independent measurement of the speed of neutrinos, with initial results expected later this year.