Opera Faster Light Nutrinos Try Again

2011 experiment which mistakenly seemed to testify faster-than-low-cal travel

Fig. i What OPERA saw. Leftmost is the proton beam from the CERN SPS accelerator. Information technology passes the beam electric current transformer (BCT), hits the target, creating first, pions and and then, somewhere in the decay tunnel, neutrinos. The cherry lines are the CERN Neutrinos to Gran Sasso (CNGS) beam to the LNGS lab where the OPERA detector is. The proton beam is timed at the BCT. The left waveform is the measured distribution of protons, and the correct that of the detected OPERA neutrinos. The shift is the neutrino travel fourth dimension. Distance traveled is roughly 731 km. At the top are the GPS satellites providing a mutual clock to both sites, making fourth dimension comparison possible. Only the PolaRx GPS receiver is in a higher place-ground, and fiber cables bring the fourth dimension underground.

In 2011, the OPERA experiment mistakenly observed neutrinos appearing to travel faster than light. Even before the source of the error was discovered, the effect was considered dissonant because speeds college than that of lite in a vacuum are more often than not thought to violate special relativity, a cornerstone of the modern understanding of physics for over a century.^{[i] [2]}

OPERA scientists announced the results of the experiment in September 2011 with the stated intent of promoting farther enquiry and debate. Later the squad reported 2 flaws in their equipment set-up that had caused errors far outside their original confidence interval: a fiber optic cable attached improperly, which caused the obviously faster-than-low-cal measurements, and a clock oscillator ticking likewise fast.^[3] The errors were beginning confirmed by OPERA after a ScienceInsider report;^[4] bookkeeping for these two sources of fault eliminated the faster-than-light results.^{[v] [6]}

In March 2012, the co-located ICARUS experiment reported neutrino velocities consistent with the speed of calorie-free in the same short-pulse beam OPERA had measured in November 2011. ICARUS used a partly different timing organisation from OPERA and measured seven different neutrinos.^[vii] In addition, the Gran Sasso experiments BOREXINO, ICARUS, LVD and OPERA all measured neutrino velocity with a short-pulsed beam in May, and obtained understanding with the speed of light.^[8]

On June 8, 2012, CERN research director Sergio Bertolucci declared on behalf of the 4 Gran Sasso teams, including OPERA, that the speed of neutrinos is consistent with that of low-cal. The press release, made from the 25th International Conference on Neutrino Physics and Astrophysics in Kyoto, states that the original OPERA results were wrong, due to equipment failures.^[8]

On July 12, 2012, OPERA updated their paper by including the new sources of errors in their calculations. They establish understanding of neutrino speed with the speed of light.^[nine]

Neutrino speeds "consistent" with the speed of light are expected given the express accuracy of experiments to date. Neutrinos have small but nonzero mass, and so special relativity predicts that they must propagate at speeds lower than that of lite. Nevertheless, known neutrino production processes impart energies far higher than the neutrino mass calibration, and then about all neutrinos are ultrarelativistic, propagating at speeds very close to that of light.

Detection [edit]

The experiment created a course of neutrinos, muon neutrinos, at CERN'due south older SPS accelerator, on the Franco–Swiss border, and detected them at the LNGS lab in Gran Sasso, Italian republic. OPERA researchers used common-view GPS, derived from standard GPS, to measure the times and place coordinates at which the neutrinos were created and detected. Equally computed, the neutrinos' average fourth dimension of flight turned out to be less than what lite would need to travel the same distance in a vacuum. In a two-week span upwards to November half-dozen, the OPERA team repeated the measurement with a unlike way of generating neutrinos, which helped measure travel fourth dimension of each detected neutrino separately. This eliminated some possible errors related to matching detected neutrinos to their cosmos time.^[10] The OPERA collaboration stated in their initial press release that further scrutiny and independent tests were necessary to definitely ostend or abnegate the results.^[viii]

Kickoff results [edit]

In a March 2011 analysis of their data, scientists of the OPERA collaboration reported evidence that neutrinos they produced at CERN in Geneva and recorded at the OPERA detector at Gran Sasso, Italy, had traveled faster than lite. The neutrinos were calculated to take arrived approximately 60.vii nanoseconds (60.7 billionths of a second) sooner than light would have if traversing the same distance in a vacuum. After vi months of cross checking, on September 23, 2011, the researchers announced that neutrinos had been observed traveling at faster-than-low-cal speed.^[11] Similar results were obtained using higher-free energy (28 GeV) neutrinos, which were observed to cheque if neutrinos' velocity depended on their energy. The particles were measured arriving at the detector faster than light past approximately one part per 40,000, with a 0.2-in-a-one thousand thousand take chances of the issue being a false positive, bold the fault were entirely due to random furnishings (significance of half dozen sigma). This measure included estimates for both errors in measuring and errors from the statistical procedure used. It was, nonetheless, a measure of precision, not accuracy, which could be influenced past elements such as incorrect computations or wrong readouts of instruments.^{[12] [13]} For particle physics experiments involving standoff data, the standard for a discovery proclamation is a five-sigma error limit, looser than the observed six-sigma limit.^[xiv]

The preprint of the inquiry stated "[the observed] deviation of the neutrino velocity from c [speed of light in vacuum] would exist a striking issue pointing to new physics in the neutrino sector" and referred to the "early arrival time of CNGS muon neutrinos" as an "anomaly".^[fifteen] OPERA spokesperson Antonio Ereditato explained that the OPERA team had "not establish whatever instrumental result that could explain the outcome of the measurement".^[8] James Gillies, a spokesperson for CERN, said on September 22 that the scientists were "inviting the broader physics community to wait at what they [had] done and really scrutinize it in bang-up detail, and ideally for someone elsewhere in the world to echo the measurements".^[xvi]

Internal replication [edit]

Fig. 2 Analysis of the internal replication in November. Distribution of the early-arrival values for each detected neutrino with bunched-beam rerun. The mean value is indicated by the ruby line and the blue band.

In Nov, OPERA published refined results where they noted their chances of being wrong as even less, thus tightening their error bounds. Neutrinos arrived approximately 57.8 ns before than if they had traveled at lite-speed, giving a relative speed difference of approximately one part per 42,000 against that of light. The new significance level became 6.2 sigma.^[17] The collaboration submitted its results for peer-reviewed publication to the Journal of High Free energy Physics.^{[18] [nineteen]}

In the same paper, the OPERA collaboration also published the results of a repeat experiment running from October 21, 2011 to November seven, 2011. They detected twenty neutrinos consistently indicating an early neutrino arrival of approximately 62.1 ns, in understanding with the outcome of the main assay.^[20]

Measurement errors [edit]

In Feb 2012, the OPERA collaboration announced two possible sources of error that could have significantly influenced the results.^[8]

• A link from a GPS receiver to the OPERA chief clock was loose, which increased the delay through the fiber. The glitch's event was to subtract the reported flight fourth dimension of the neutrinos past 73 ns, making them seem faster than light.^{[21] [22]}
• A clock on an electronic lath ticked faster than its expected 10 MHz frequency, lengthening the reported flight-time of neutrinos, thereby somewhat reducing the seeming faster-than-low-cal effect. OPERA stated the component had been operating outside its specifications.^[23]

In March 2012 an LNGS seminar was held, confirming the fiber cable was not fully screwed in during information gathering.^[5] LVD researchers compared the timing data for cosmic high-energy muons hitting both the OPERA and the nearby LVD detector between 2007 and 2008, 2008–2011, and 2011–2012. The shift obtained for the 2008–2011 menses agreed with the OPERA anomaly.^[24] The researchers also found photographs showing the cable had been loose by October 13, 2011.^[25]

Correcting for the two newly found sources of error, results for neutrino speed appear to exist consistent with the speed of light.^[5]

End results [edit]

On July 12, 2012 the OPERA collaboration published the end results of their measurements between 2009 and 2011. The divergence between the measured and expected inflow time of neutrinos (compared to the speed of light) was approximately 6.5 ± 15 ns. This is consequent with no departure at all, thus the speed of neutrinos is consequent with the speed of light within the margin of error. Also the re-analysis of the 2011 bunched beam rerun gave a similar result.^[ix]

Contained replication [edit]

In March 2012, the co-located ICARUS experiment refuted the OPERA results by measuring neutrino velocity to be that of calorie-free.^[vii] ICARUS measured speed for seven neutrinos in the aforementioned short-pulse beam OPERA had checked in November 2011, and found them, on average, traveling at the speed of low-cal. The results were from a trial run of neutrino-velocity measurements slated for May.^[26]

In May 2012, a new bunched axle rerun was initiated by CERN. Then in June 2012, it was announced past CERN that the iv Gran Sasso experiments OPERA, ICARUS, LVD, and BOREXINO measured neutrino speeds consistent with the speed of lite, indicating that the initial OPERA result was due to equipment errors.^[8]

In addition, Fermilab stated that the detectors for the MINOS projection were beingness upgraded.^[27] Fermilab scientists closely analyzed and placed premises on the errors in their timing system.^[28] On June 8, 2012 MINOS announced that according to preliminary results, the neutrino speed is consistent with the speed of light.^[29]

The measurement [edit]

The OPERA experiment was designed to capture how neutrinos switch betwixt different identities, just Autiero realized the equipment could exist used to precisely measure out neutrino speed as well.^[xxx] An earlier result from the MINOS experiment at Fermilab demonstrated that the measurement was technically viable.^[31] The principle of the OPERA neutrino velocity experiment was to compare travel time of neutrinos against travel fourth dimension of light. The neutrinos in the experiment emerged at CERN and flew to the OPERA detector. The researchers divided this distance past the speed of light in vacuum to predict what the neutrino travel time should be. They compared this expected value to the measured travel fourth dimension.^[32]

Overview [edit]

The OPERA team used an already existing beam of neutrinos traveling continuously from CERN to LNGS, the CERN Neutrinos to Gran Sasso beam, for the measurement. Measuring speed meant measuring the distance traveled by the neutrinos from their source to where they were detected, and the time taken by them to travel this length. The source at CERN was more than 730 kilometres (450 mi) away from the detector at LNGS (Gran Sasso). The experiment was tricky because there was no manner to time an individual neutrino, necessitating more complex steps. As shown in Fig. i, CERN generates neutrinos by slamming protons, in pulses of length 10.5 microseconds (10.5 millionths of a 2d), into a graphite target to produce intermediate particles, which decay into neutrinos. OPERA researchers measured the protons as they passed a section called the beam current transducer (BCT) and took the transducer's position as the neutrinos' starting point. The protons did non actually create neutrinos for another kilometer, merely because both protons and the intermediate particles moved almost at light speed, the error from the assumption was passably low.

The clocks at CERN and LNGS had to be in sync, and for this the researchers used high-quality GPS receivers, backed up with diminutive clocks, at both places. This system timestamped both the proton pulse and the detected neutrinos to a claimed accuracy of 2.3 nanoseconds. Merely the timestamp could not be read like a clock. At CERN, the GPS signal came just to a receiver at a central control room, and had to be routed with cables and electronics to the computer in the neutrino-beam command room which recorded the proton pulse measurement (Fig. iii). The filibuster of this equipment was 10,085 nanoseconds and this value had to be added to the time postage stamp. The information from the transducer arrived at the figurer with a 580 nanoseconds delay, and this value had to be subtracted from the fourth dimension postage. To get all the corrections right, physicists had to measure exact lengths of the cables and the latencies of the electronic devices. On the detector side, neutrinos were detected past the charge they induced, non past the light they generated, and this involved cables and electronics as office of the timing chain. Fig. 4 shows the corrections practical on the OPERA detector side.

Since neutrinos could not be accurately tracked to the specific protons producing them, an averaging method had to be used. The researchers added up the measured proton pulses to get an boilerplate distribution in time of the individual protons in a pulse. The time at which neutrinos were detected at Gran Sasso was plotted to produce another distribution. The two distributions were expected to have similar shapes, but be separated by 2.iv milliseconds, the fourth dimension it takes to travel the distance at light speed. The experimenters used an algorithm, maximum likelihood, to search for the time shift that best fabricated the two distributions to coincide. The shift and so calculated, the statistically measured neutrino arrival fourth dimension, was approximately 60 nanoseconds shorter than the two.four milliseconds neutrinos would accept taken if they traveled just at calorie-free speed. In a later experiment, the proton pulse width was shortened to 3 nanoseconds, and this helped the scientists to narrow the generation time of each detected neutrino to that range.^[33]

Measuring distance [edit]

Distance was measured by accurately fixing the source and detector points on a global coordinate system (ETRF2000). CERN surveyors used GPS to measure the source location. On the detector side, the OPERA team worked with a geodesy group from the Sapienza University of Rome to locate the detector's centre with GPS and standard map-making techniques. To link the surface GPS location to the coordinates of the underground detector, traffic had to be partially stopped on the admission route to the lab. Combining the two location measurements, the researchers calculated the distance,^[34] to an accuracy of twenty cm within the 730 km path.^[35]

Measuring trip fourth dimension [edit]

Fig. 3 CERN SPS/CNGS time measuring arrangement. Protons circulate in the SPS till kicked by a indicate to the beam current transformer (BCT) and on to the target. The BCT is the origin for the measurement. Both the kicker betoken and the proton flux in the BCT get to the waveform digitizer (WFD), the first through the Control Timing Receiver (CTRI). The WFD records the proton distribution. The mutual CNGS/LNGS clock comes from GPS via the PolaRx receiver and the primal CTRI, where the CERN UTC and General Machine Timing (GMT) also go far. The difference betwixt the two references is recorded. The marker x ± y indicates an 'x' nanosecond delay with a 'y' ns error bound.

Fig. four OPERA fourth dimension measuring system at LNGS: various delays of the timing concatenation, and the standard deviations of the error. The top half of the picture is the mutual GPS clock arrangement (PolaRx2e is the GPS receiver), and the bottom half is the clandestine detector. Fiber cables bring the GPS clock underneath. The clandestine detector consists of the blocks from the tt-strip to the FPGA. Errors for each component are shown as x ± y, where ten is the delay caused past the component in transmitting time information, and y is the expected spring on that filibuster.

Timing systems at the two ends of the OPERA experiment

The travel fourth dimension of the neutrinos had to be measured by tracking the time they were created, and the fourth dimension they were detected, and using a common clock to ensure the times were in sync. As Fig. 1 shows, the time measuring system included the neutrino source at CERN, the detector at LNGS (Gran Sasso), and a satellite element common to both. The common clock was the time bespeak from multiple GPS satellites visible from both CERN and LNGS. CERN's beams-department engineers worked with the OPERA team to provide a travel fourth dimension measurement between the source at CERN and a point merely earlier the OPERA detector's electronics, using accurate GPS receivers. This included timing the proton beams' interactions at CERN, and timing the cosmos of intermediate particles somewhen decomposable into neutrinos (see Fig. 3).

Researchers from OPERA measured the remaining delays and calibrations not included in the CERN calculation: those shown in Fig. 4. The neutrinos were detected in an surreptitious lab, but the common clock from the GPS satellites was visible only above footing level. The clock value noted above-ground had to be transmitted to the underground detector with an 8 km fiber cablevision. The delays associated with this transfer of time had to be accounted for in the calculation. How much the error could vary (the standard deviation of the errors) mattered to the analysis, and had to exist calculated for each part of the timing concatenation separately. Special techniques were used to measure the length of the fiber and its consequent delay, required as role of the overall calculation.^[34]

In addition, to sharpen resolution from the standard GPS 100 nanoseconds to the ane nanosecond range metrology labs reach, OPERA researchers used Septentrio's precise PolaRx2eTR GPS timing receiver,^[36] along with consistency checks across clocks (time scale procedures) which allowed for common-view time transfer. The PolaRx2eTR allowed measurement of the fourth dimension commencement between an atomic clock and each of the Global Navigation Satellite Organisation satellite clocks. For calibration, the equipment was taken to the Swiss Metrology Establish (METAS).^[34] In addition, highly stable cesium clocks were installed both at LNGS and CERN to cantankerous-check GPS timing and to increase its precision. Later on OPERA plant the superluminal issue, the fourth dimension scale was rechecked both past a CERN engineer and the German Institute of Metrology (PTB).^[34] Time-of-flight was eventually measured to an accuracy of 10 nanoseconds.^{[viii] [37]} The final error bound was derived by combining the variance of the error for the individual parts.

The assay [edit]

The OPERA team analyzed the results in different ways and using dissimilar experimental methods. Following the initial principal analysis released in September, 3 further analyses were fabricated public in November. In the main November assay, all the existing information were reanalyzed to allow adjustments for other factors, such as the Sagnac effect in which the Globe's rotation affects the distance traveled by the neutrinos. Then an culling analysis adopted a different model for the matching of the neutrinos to their creation time. The third analysis of November focused on a dissimilar experimental setup ('the rerun') which changed the way the neutrinos were created.

In the initial setup, every detected neutrino would take been produced onetime in a x,500 nanoseconds (10.5 microseconds) range, since this was the elapsing of the proton beam spill generating the neutrinos. It was not possible to isolate neutrino production time further inside the spill. Therefore, in their main statistical analyses, the OPERA group generated a model of the proton waveforms at CERN, took the various waveforms together, and plotted the take a chance of neutrinos being emitted at various times (the global probability density office of the neutrino emission times). They then compared this plot against a plot of the arrival times of the 15,223 detected neutrinos. This comparing indicated neutrinos had arrived at the detector 57.8 nanoseconds faster than if they had been traveling at the speed of light in vacuum. An alternative analysis in which each detected neutrino was checked confronting the waveform of its associated proton spill (instead of confronting the global probability density function) led to a compatible outcome of approximately 54.v nanoseconds.^[38]

The November chief analysis, which showed an early inflow time of 57.8 nanoseconds, was conducted bullheaded to avoid observer bias, whereby those running the analysis might inadvertently fine-tune the result toward expected values. To this stop, old and incomplete values for distances and delays from the year 2006 were initially adopted. With the final correction needed non yet known, the intermediate expected result was also an unknown. Analysis of the measurement data under those 'blind' conditions gave an early neutrino arrival of 1043.four nanoseconds. Afterward, the data were analyzed once more taking into consideration the consummate and actual sources of errors. If neutrino and light speed were the same, a subtraction value of 1043.4 nanoseconds should have been obtained for the correction. Nevertheless, the actual subtraction value amounted to merely 985.vi nanoseconds, respective to an arrival time 57.8 nanoseconds earlier than expected.^[17]

Two facets of the outcome came under particular scrutiny within the neutrino community: the GPS synchronization system, and the profile of the proton beam spill that generated neutrinos.^[11] The second business organization was addressed in the November rerun: for this analysis, OPERA scientists repeated the measurement over the same baseline using a new CERN proton beam which circumvented the need to make whatever assumptions about the details of neutrino production during the beam activation, such every bit energy distribution or production rate. This axle provided proton pulses of 3 nanoseconds each with up to 524 nanosecond gaps. This meant a detected neutrino could be tracked uniquely to its generating 3 nanoseconds pulse, and hence its start and end travel times could be directly noted. Thus, the neutrino's speed could now be calculated without having to resort to statistical inference.^[8]

In addition to the four analyses mentioned before—September main analysis, Nov main analysis, alternative analysis, and the rerun analysis—the OPERA team also split the information by neutrino free energy and reported the results for each fix of the September and November main analyses. The rerun analysis had as well few neutrinos to consider splitting the fix further.

[edit]

After the initial study of apparent superluminal velocities of neutrinos, near physicists in the field were quietly skeptical of the results, but prepared to prefer a wait-and-come across approach. Experimental experts were aware of the complexity and difficulty of the measurement, and then an actress unrecognized measurement error was yet a real possibility, despite the care taken by the OPERA team.^{[ citation needed ]} However, because of the widespread interest, several well-known experts did make public comments. Nobel laureates Steven Weinberg,^[39] George Smoot Three, and Carlo Rubbia,^[40] and other physicists not affiliated with the experiment, including Michio Kaku,^[41] expressed skepticism about the accuracy of the experiment on the footing that the results challenged a long-held theory consistent with the results of many other tests of special relativity.^[42] Nevertheless, Ereditato, the OPERA spokesperson, stated that no one had an caption that invalidated the experiment's results.^[43]

Previous experiments of neutrino speed played a role in the reception of the OPERA issue by the physics community. Those experiments did not detect statistically pregnant deviations of neutrino speeds from the speed of light. For instance, Astronomer Royal Martin Rees and theoretical physicists Lawrence Krauss^[39] and Stephen Hawking^[44] stated neutrinos from the SN 1987A supernova explosion arrived almost at the same time as light, indicating no faster-than-light neutrino speed. John Ellis, theoretical physicist at CERN, believed information technology difficult to reconcile the OPERA results with the SN 1987A observations.^[45] Observations of this supernova restricted x MeV anti-neutrino speed to less than 20 parts per billion (ppb) over lightspeed. This was i of the reasons most physicists suspected the OPERA team had made an error.^[32]

Physicists affiliated with the experiment had refrained from interpreting the event, stating in their paper:

Despite the big significance of the measurement reported here and the stability of the assay, the potentially great affect of the result motivates the continuation of our studies in gild to investigate possible still unknown systematic effects that could explain the observed anomaly. We deliberately do not attempt any theoretical or phenomenological interpretation of the results.^[15]

Theoretical physicists Gian Giudice, Sergey Sibiryakov, and Alessandro Strumia showed that superluminal neutrinos would imply some anomalies in the velocities of electrons and muons, as a effect of quantum-mechanical effects.^[46] Such anomalies could exist already ruled out from existing data on catholic rays, thus contradicting the OPERA results. Andrew Cohen and Sheldon Glashow predicted that superluminal neutrinos would radiate electrons and positrons and lose energy through vacuum Cherenkov effects, where a particle traveling faster than light decays continuously into other slower particles.^[47] However, this energy attrition was absent both in the OPERA experiment and in the co-located ICARUS experiment, which uses the same CNGS beam every bit OPERA.^{[1] [48]} This discrepancy was seen by Cohen and Glashow to present "a pregnant challenge to the superluminal interpretation of the OPERA data".^[47]

Many other scientific papers on the anomaly were published as arXiv preprints or in peer reviewed journals. Some of them criticized the upshot, while others tried to find theoretical explanations, replacing or extending special relativity and the standard model.^[49]

Discussions inside the OPERA collaboration [edit]

In the months after the initial declaration, tensions emerged in the OPERA collaboration.^{[l] [51] [18] [21]} A vote of no confidence among the more than xxx group team leaders failed, but spokesperson Ereditato and physics coordinator Autiero resigned their leadership positions anyhow on March xxx, 2012.^{[5] [52] [53]} In a resignation letter, Ereditato claimed that their results were "excessively sensationalized and portrayed with not e'er justified simplification" and defended the collaboration, stating, "The OPERA Collaboration has e'er acted in full compliance with scientific rigor: both when it appear the results and when it provided an caption for them."^[54]

See besides [edit]

• Measurements of neutrino speed
• GSI anomaly

Notes [edit]

1. ^ ^{a b} Reich (2011b).
2. ^ Many sources describe faster-than-light (FTL) as violating special relativity (SR): (Reich (2011c); Cho (2011a); Choi (2011)). Other reliable sources disagree, though; for FTL not necessarily violating SR, see "Tachyon" (2011).
3. ^ Strassler, G. (2012) "OPERA: What Went Wrong" profmattstrassler.com
4. ^ Cartlidge (2012a); Cartlidge (2012b)
5. ^ ^{a b c d} Eugenie Samuel Reich (Apr ii, 2012), "Embattled neutrino project leaders stride down", Nature News, doi:10.1038/nature.2012.10371, S2CID 211730430, retrieved April 2, 2012
6. ^ Reich (2012c).
7. ^ ^{a b} ICARUS (2012b).
8. ^ ^{a b c d due east f g h} "OPERA experiment reports anomaly in flying time of neutrinos from CERN to Gran Sasso" (2011)
9. ^ ^{a b} OPERA (2012).
10. ^ Cartlidge (2011b).
11. ^ ^{a b} Reich (2011a).
12. ^ Brunetti (2011).
13. ^ OPERA (2011a).
14. ^ Seife (2000).
15. ^ ^{a b} OPERA (2011a), p. 29.
16. ^ Jordans & Borenstein (2011a).
17. ^ ^{a b} OPERA (2011b).
18. ^ ^{a b} Cartlidge (2011c).
19. ^ Jha (2011).
20. ^ "A new proton spill from CERN to Gran Sasso" (2011); OPERA (2011b)
21. ^ ^{a b} Cartlidge (2012c).
22. ^ Lindinger & Hagner (2012).
23. ^ "Scientific discipline in action" (2012)
24. ^ LVD and OPERA (2012).
25. ^ Sirri, Gabriele (March 28, 2012). "Measurements and cross checks 
on OPERA timing equipments". Istituto Nazionale di Fisica Nucleare (Powerpoint presentation). p. 8. Archived from the original on February ten, 2022. Retrieved February 10, 2022.
26. ^ Jordans (2012).
27. ^ Hooker (2011).
28. ^ Pease (2011).
29. ^ "MINOS reports new measurement of neutrino velocity". Fermilab Today. June 8, 2012. Retrieved June 8, 2012.
30. ^ Nosengo (2011)
31. ^ Cartlidge (2011a).
32. ^ ^{a b} Cho (2011b).
33. ^ The CERN-neutrino-to-Gran-Sasso beam commendation is from "Upstream from OPERA: extreme attention to detail" (2011); the rest of the clarification draws heavily on the article past Cho (2011b), and, to some extent, by Cartlidge (2011b).
34. ^ ^{a b c d} "Upstream from OPERA: farthermost attending to detail" (2011)
35. ^ Colosimo et al. (2011).
36. ^ "Knocking Einstein: Septentrio in CERN experiment" (2011).
37. ^ Feldmann (2011); Komatsu (2011)
38. ^ OPERA (2011), pp. xiv, 16–21. sfnp fault: no target: CITEREFOPERA2011 (help)
39. ^ ^{a b} Matson (2011).
40. ^ Padala (2011).
41. ^ Jordans & Borenstein (2011b).
42. ^ Reich (2011c); Cho (2011b); Overbye (2011); Gary (2011)
43. ^ Palmer (2011).
44. ^ "Hawking on the future of mankind" (2012).
45. ^ Brumfiel (2011).
46. ^ Giudice, Sibiryakov & Strumia (2011)
47. ^ ^{a b} Cohen & Glashow (2011)
48. ^ ICARUS (2012a).
49. ^ Resource listing at INFN SuperLuminal Neutrino, archived from the original on September two, 2012
50. ^ Grossman (2011a).
51. ^ Grossman (2011b).
52. ^ Cartlidge (2012d).
53. ^ Grossman (2012b).
54. ^ Antonio Ereditato (March thirty, 2012). "OPERA: Ereditato's Betoken of View". Le Scienze.

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External links [edit]

• OPERA: What Went Incorrect
• BBC documentary on the OPERA effect
• OPERA Principal Page
• CNGS Neutrino axle at CERN
• OPERA publications
• Webcast of OPERA neutrino bibelot presentation past Dario Autiero
• Works which cite the OPERA result
• Resource list of The Net Advance of Physics
• Some other summary of OPERA-related arXiv papers
• CERN OPERA neutrinos travel faster than light, September 22, 2011, YouTube
• The Neutrinos CERN interview.faster than light Einstein might have been wrong?! HD, YouTube, September 23, 2011
• CERN/LNGS researchers' discussion of how to bank check the time transfer

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Source: https://en.wikipedia.org/wiki/Faster-than-light_neutrino_anomaly