GPS接收器信号错误使中微子超越光速。。
针对去年9月份我们关于这个话题的讨论：http://www.ourdev.cn/bbs/bbs_content.jsp?bbs_sn=5071058&bbs_page_no=1&search_mode=1&search_text=光速&bbs_id=9999
对于这个错误的解释：GPS接收器信号错误使中微子超越光速
http://news.3snews.net/technology/20120223/18787.shtml
全文：
据著名期刊美国《科学》杂志网站报道，接近CERN实验者的消息来源透露，去年9月意大利实验室所作的中微子速度超光速结果终于有了解释：GPS信号接收器和PC之间的光缆没接好导致的系统误差造成了这一假象。
此前已经有更多的研究人员站出来称这一与相对论矛盾的实验结果是由于某种还未发现的系统误差所导致，并且相对论在“发现”之后至今的近一百年间已经为多个实验所证实。这次正是如此：研究人员发现检查连接用来校正中微子飞行时间的GPS信号接收器和PC的光缆后，此前中微子比光速快60ns的实验结果就可得到解释。具体进展还需等待进一步证实以及发表正式文章之后。 没接好能导致60ns误差？我估计最后还是光缆长度不对。 要是相对论有问题是不是所有的核电站都要推倒重建？ 回复【1楼】gzhuli 咕唧霖
-----------------------------------------------------------------------
具体细节我也没找到，反正是电视上面和网络上来看，实验室承认错误啦。
回复【2楼】fsclub 绿林好汉
-----------------------------------------------------------------------
相对论和核电站有这么大关系？
顶多就是单位质量放出的能量变多变少吧。 这世道，难讲，有可能真的超越光速了，担心影响太大，特意出来辟谣的。
瞎猜的，别当真就行。其实神马都是浮云，一颗沙子里就有个宇宙呢。 《科学》杂志原文和文中提到的相关信息来源：
http://news.sciencemag.org/scienceinsider/2012/02/breaking-news-error-undoes-faster.html
BREAKING NEWS: Error Undoes Faster-Than-Light Neutrino Results
by Edwin Cartlidge on 22 February 2012, 1:45 PM| 199 Comments
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.
http://news.sciencemag.org/scienceinsider/2012/02/official-word-on-superluminal-ne.html?ref=hp
Official Word on Superluminal Neutrinos Leaves Warp-Drive Fans a Shred of Hope—Barely
by Edwin Cartlidge on 24 February 2012, 11:31 AM| 17 Comments
The CERN particle physics laboratory in Geneva has confirmed Wednesday's report that a loose fiber-optic cable may be behind measurements that seemed to show neutrinos outpacing the speed of light. But the lab also says another glitch could have caused the experiment to underestimate the particles' speed.
In a statement based on an earlier press release from the OPERA collaboration, CERN said two possible "effects" may have influenced the anomalous measurements. One of them, due to a possible faulty connection between the fiber-optic cable bringing the GPS signals to OPERA and the detector's master clock, would have caused the experiment to underestimate the neutrinos' flight time, as described in the original story. The other effect concerns an oscillator, part of OPERA's particle detector that gives its readings time stamps synchronized to GPS signals. Researchers think correcting for an error in this device would actually increase the anomaly in neutrino velocity, making the particles even speedier than the earlier measurements seemed to show.
CERN's statement says OPERA scientists are studying the "potential extent of these two effects" but doesn't indicate which source of error (if either) is likely to outweigh the other. However, Lucia Votano, director of the Gran Sasso laboratory, says the "main suspicion" focuses on the optical-fiber connection. She adds that OPERA researchers deserve credit for "having tenaciously followed this particular evidence via checks completed in the last few days."
The two effects will get a new round of tests in May, when the two labs are scheduled to make velocity measurements with short-pulsed beams designed to give readings much more precise than scientists have achieved so far.
http://blogs.nature.com/news/2012/02/faster-than-light-neutrino-measurement-has-two-possible-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 travelling 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, Switzerland, and sent 730 kilometres to its detector at Gran Sasso National Laboratory in Italy were arriving 60 nanoseconds faster than a light beam would take to travel the same distance. Many physicists were skeptical but the measurement seemed to have been done carefully 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 that 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 that 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. 三个中微子走进酒吧，侍者问 “三位都要来一杯咖啡么？”第一个说：“是的！”，第二个说：“我也不知道。” 第三个说：“不知道。”侍者默默去插好了线缆回来，说：“给我好好再说一遍！” 回复【5楼】gzhuli 咕唧霖
-----------------------------------------------------------------------
你这个和我在lz说的一样。 原子_弹也好，核电站也好，都不是基于相对论的，是基于质能方程的, E=mc平方. 回复【8楼】skylly3
原子_弹也好，核电站也好，都不是基于相对论的，是基于质能方程的, e=mc平方.
-----------------------------------------------------------------------
质能方程就是基于相对论吧。 回复【9楼】lxvtag团长
-----------------------------------------------------------------------
关于你头像的Joke:
老师问：谁知道皮肤的作用。
学生答：为了让你看起来不致于太恐怖！ 回复【7楼】USACH 美丽坚和中国
回复【5楼】gzhuli 咕唧霖
-----------------------------------------------------------------------
你这个和我在lz说的一样。
-----------------------------------------------------------------------
不一样，前两篇文章是LZ位文章的原文出处，仅提到“光纤没接好”，但最后一篇文章的最后一段引述的OPERA声明全文才是关键：
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.
文中提到，目前发现两个问题，这两个问题对时间的影响是相反的：一个是和GPS同步的用于产生时间戳的基准时钟没有正确插值，另一个是将GPS信号引入主时钟的光纤连接。这里我认为文中的connection并不是指“没接好”，而是指整个光纤链路出了问题，最有可能的就是长度量错了，或许是某个临时维修工换了一根长度不一样的光纤上去（中国官方标准解释，呵呵）。 回复【11楼】gzhuli 咕唧霖
-----------------------------------------------------------------------
我就看了前一段…… 回复【12楼】USACH 美丽坚和中国
回复【11楼】gzhuli 咕唧霖
-----------------------------------------------------------------------
我就看了前一段……
-----------------------------------------------------------------------
这些科学家们啊，都成精了。
之前仅发表数据，不下任何结论，自己品味去。
现在只说找到两个潜在问题，不发表任何数据，自己猜去。 回复【13楼】gzhuli 咕唧霖
-----------------------------------------------------------------------
我觉得国外的研究所还好吧。毕竟《科学》不像国内的杂志。 回复【14楼】USACH 美丽坚和中国
-----------------------------------------------------------------------
呵呵，没看出我调侃国内那些砖家的么，动不动就下结论，吹水不上税的。 回复【15楼】gzhuli 咕唧霖
-----------------------------------------------------------------------
额，这个太冷啦……
页:
[1]