To save chestnut trees, we may have to play God, Why you should add native plants to your garden, What you can do right now to advocate for the planet, Why poison ivy is an unlikely climate change winner, The gory history of Europes mummy-eating fad, This ordinary woman hid Anne Frankand kept her story alive, This Persian marvel was lost for millennia. Those neutrinos might be all around us, as an inevitable part of the galaxy, but we cannot directly detect them. Neutrino oscillation might, for example, then make early neutrino more detectable by the distant detector. Given how big this question is, maybe it would be best to delete this answer? Another reason to disbelieve it is that there are strong and fairly model-independent reasons to believe that it cannot be correct. There are a myriad of ways the neutrino has shown itself to us, and each one provides us with an independent measurement and constraint on its properties. (I actually had something similar happen to me on an experiment: I had an analog signal splitter "upstairs" that sent a signal echo back to my detectors "downstairs", and a runty little echoed pulse came back upstairs after about a microsecond and got processed like another event. Is there a generic term for these trajectories? Ask Ethan: Do Neutrinos Always Travel At Nearly The Speed Of Light? The paper is on arXiv; a webcast is/was planned here. I'm quite impressed that they had ~100ns timing resolution between the two laboratories; the "discovery" came about because they were trying to do ten times better than that. As the Earth moves we observe a dipole, and in different directions we measure different wavelengths for the same physical object (photon). The lowest-energy neutrinos weve ever detected have so much energy that their speed must be, at minimum, 99.99999999995% the speed of light, which means that they can move no slower than 299,792,457.99985 meters-per-second. (Unless the neutrinos are tachyons; in that case, I guess Lorentz invariance is technically still intact, but the observation of a tachyon would be equally big news.). Faster Than Ignoring the boilerplate media hype about the possibilities of time travel and alternate dimensions - I'm looking for academic sources that might suggest how this could be true, or alternatively, how this discrepancy could be accounted for. Divide distance by time, and the particles must have been traveling 0.0025 percent faster than the speed of light in a vacuum. [This paragraph is disproved by the Nov. 17 result.] decay at the time. @jonathan light travels at a velocity below c in fibre optic cable. Anyway, I'll be interested in seeing how it pans out. Faster-than-light neutrino experiment to @MSalters: I agree. Inside South Africas skeleton trade. Physics Neutrino watch: Speed claim baffles it is unlikely that the neutrinos go superluminal or SR is not holding true anymore, it is unlikely that the distance is measured incorreclty, it is unlikely that the GPS setup/usage is incorrect. The arXiv paper studied them, and seem to exclude it. The official announcement of the result, on September 23 at the European physics laboratory CERN near Geneva, was met with cheering but also with a barrage of questions from those scrutinizing the experiment for unknown sources of error that may be misleading the physicists. Why don't we use the 7805 for car phone chargers? One of the most common skepticism of people who no nothing about the experiment is stuff like: You might worry about[] have they correctly accounted for the time delay of actually reading out the signals? Thats what Patreon supporter Laird Whitehill wants to know, asking: I know neutrinos travel almost at the speed of light. Either energy and momentum were being lost, and these supposedly fundamental conservation laws were no good, or there was a hitherto undetected additional particle being created that carried that excess energy and momentum away. Last (?) But, it's still possible! They can change flavor from one type (electron, mu, tau) into another. It is less important that the rotation of the Earth. Site design / logo 2023 Stack Exchange Inc; user contributions licensed under CC BY-SA. As such, it is comparable to an object spontaneously heating up in a cold environment. These are simple measurements that could be checked in an afternoon by a competent 2nd-year grad student. The idea that nothing can exceed the speed of light in a vacuum forms a cornerstone in physics - first laid out by James Clerk Maxwell and later incorporated into Albert Einstein's theory of special relativity. IMO what really needs to happen now is two things: (1) Other groups will try to reproduce the anomaly. It's a direct measurement of average velocity. If you get rid of the speed limit principle, the magnetic field cannot exist anymore. The community was properly incredulous and the wide interest prompted a large number of other checks they could make. Initial analysis of the work by the wider scientific community argued that the relatively long-lasting bunches of neutrinos could introduce a significant error into the measurement. Subscribers, enter your e-mail address for full access to the Science News archives and digital editions. IMO this is only possible if they are synchronised as in the above paper (instant observer) and not in the Einstein way that only considers one path between the observer and any other point (Synchronisation around the circumference of a rotating disk gives a non vanishing time difference that depends on the direction used). What is detected is watermark patterns in the steady stream of particles. the atomic number of the nucleus changed by 2. but 0 neutrinos or antineutrinos are emitted. They discard one of the basic assumptions of relativity, a symmetry that makes the laws of physics look the same when viewed from different reference frames. Are Neutrinos not faster than light Only one ancient account mentions the existence of Xerxes Canal, long thought to be a tall tale. I found that odd given that they do have a downstream muon detector system, but they may be concerned about backgrounds. The solar and atmospheric neutrino experiment results are consistent with one another, but not with the full suite of neutrino data including beamline neutrinos. The issue we have is twofold: The only neutrino interactions we see are the ones coming from neutrinos moving indistinguishably close to the speed of light. In 2004 Mewes and Alan Kostelecky of Indiana University in Bloomington published a paper in Physical Review D describing one such theory. Speedy neutrino result may be due to instrument glitch, http://www.newscientist.com/blogs/shortsharpscience/2012/02/speedy-neutrino-result-may-be.html, Loose Cable Explains Faulty 'Faster-than-light' Neutrino Result, http://www.space.com/14654-error-faster-light-neutrinos.html?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+spaceheadlines+%28SPACE.com+Headline+Feed%29. This phenomena may have been explained. The MAJORANA experiment, shown here, has the potential to finally detect this rare decay. Lets dive on in. It is likely to be several months before they report back. This means that the shift can only be detected statistically, and it makes the result extremely vulnerable to unanticipated systematic errors, e.g., correlations between the time of emission of the neutrinos and their energy (which strongly affects the efficiency of detection) or the direction of emission. E.g., it holds both for tachyonic neutrinos without a preferred frame and for models in which neutrinos are not tachyonic and there is a preferred frame. Note that the author of the pre-print you link in you edit has. What happened to the idea of tachyonic or other superluminal neutrinos? ", Oscillation Project with Emulsion-tRacking Apparatus, or OPERA, Do Not Sell or Share My Personal Information. You have a few longer answers which were already updated, but here is a concise statement of the situation in mid-2014: An independent measurement by the ICARUS collaboration, also using neutrinos traveling from CERN to Gran Sasso but using independent detector and timing hardware, found detection times "compatible with the simultaneous arrival of all events with equal speed, the one of light.". "This is reinforcing the previous finding and ruling out some possible systematic errors which could have in principle been affecting it," said Antonio Ereditato of the Opera collaboration. WebAs I have been researching I've come up on many articles claiming that Neutrinos can go faster than the speed of light a miniscule amount but still faster. MINOS will soon upgrade its equipment with snazzy new atomic clocks, says Rob Plunkett, a Fermilab physicist working on a MINOS experiment. It seems to indicate that you could transform a matter particle (a neutrino) into an antimatter particle (an antineutrino) simply by changing your motion relative to the neutrino. Neutrino 'faster than light' scientist resigns - BBC News @Carl: and this is supposed to make one trust their report, independent measurement by the ICARUS collaboration, Times of Flight between a Source and a Detector observed from a GPS satelite, Measurement of the neutrino velocity with the OPERA detector in the CNGS beam, arxiv.org/ftp/arxiv/papers/1109/1109.4897.pdf, Cosmological Principle and Relativity - Part I, Improving the copy in the close modal and post notices - 2023 edition, New blog post from our CEO Prashanth: Community is the future of AI. Neutrinos might have mass, but their mass is so small that of all the ways the Universe has to create them, only the neutrinos made in the Big Bang itself should be moving slow compared to the speed of light today. Standard Big Bang cosmology corresponds to =1. The new, preliminary result shows that neutrinos arrived at OPERA 1.6 nanoseconds slower than light would have, with an error of 6.2 nanoseconds. A bad cable connector can take a beautiful digital logic signal and reflect part of it back to the emitter, in a time-dependent way, turning the received signal into an analog mess with a complicated shape. That mission has never been more important than it is today. The Special Theory of Relativity (STR) of Einstein, through the principle of the speed limit, makes the magnetic force come from the electric one and the magnetic force is an electric force, as physicists know; an easy demonstration of that can be found in chapter 3 of my file at the following link (also English inside): http://www.fisicamente.net/FISICA_2/UNIFICAZIONE_GRAVITA_ELETTROMAGNETISMO.pdf. "If things travel faster than the speed of light, A can cause B, [but] B can also cause A," Parke said. "So far no arguments have been put forward that rule out our effect," Dr Ereditato said. Neutrino experiment repeat at Cern finds same result - BBC News Everybodys bias in responding to this is going to be that this is some sort of systematic uncertainty that they didnt figure out.. Extracting arguments from a list of function calls. All particles show the same speed limit as light, yet neutrinos with a rest mass greater than light possess a larger speed limit? Inevitably, if this turned out to be the case, the real upper limit is slightly higher again, since neutrinos are massive and thus move below the maximum speed. Does eating close to bedtime make you gain weight? As a nonprofit news organization, we cannot do it without you. You can clearly see that the timing offset was introduced in mid-2008 and not corrected until the end of 2011. Like most scientists, my guess is an unaccounted for systematic error (because they definitely have statistical significance and precision on their side) that has yet to be pointed out, but it probably won't take too long with all the theoretical physicists that will be pouring through this experiment. (I'm a theorist, BTW; you do not have to be an experimentalist to acknowledge that. It's just unlikely, very unlikely, just as the 4-sigma evidence for new CP violation in like-sign dimuons was possible, only to fall flat on its face when ATLAS and CMS failed to see the same thing. If so, would it be a real violation of Lorentz invariance or an "almost, but not quite" effect. And yet neutrinos and antineutrinos, despite appearing to move at the speed of light, must have a non-zero rest mass, otherwise this neutrino oscillation phenomenon would not be possible. Given the sheer diversity of possible `goof-up' explanations on this page (all answers combined), I can't help feeling that we are trying to find one plausible way in which this can be MADE to look wrong. We end up with statistical errors. When Physicists thought neutrinos were faster than the speed of light. Fermilab might have a better shot. Can you plausibly make a 60ns delay by a loose cable? In theory, because neutrinos have a non-zero rest mass, it should be possible for them to slow down to non-relativistic speeds. It looks like they took an insane amount of care with their measurement of distance and time. Generating points along line with specifying the origin of point generation in QGIS. I'm sure they spent an entire year shitting pineapples because they couldn't identify the problem. I suspect that the syncronization used in the GPS is in the same as in the above paper and not as Einstein did. Other proposals could accommodate faster-than-light travel with violating this principle of relativity, says Lee Smolin, a theoretical physicist at the Perimeter Institute for Theoretical Physics in Waterloo, Canada. If neutrinos really traveled faster than the speed of light, the supernova's neutrinos should have arrived in 1983, not 1987. Sources: [1] (Associated Press), [2] (Guardian.co.uk), [3] (Original Publication - Cornell University). This means that the neutrino will have a slightly shorter distance to travel than it would if the experiment were stationary. @Ron, any (general) relativistic effect cannot make the speed superluminal, but it can make your length measurement based on GPS incorrect. faster than light - Superluminal neutrinos - Physics Stack Exchange But since they have mass, there is no reason that they couldnt travel at any speed. matter, it will have a certain probability of oscillating, something that can only happen if neutrinos have very small but non-zero masses. There have been plenty of papers (well, preprints) have been put forward offering various explanations of the OPERA results, but none of them has been widely accepted yet as far as I know so it's rather premature to say the results have been explained. Previous experiments of neutrino speed played a role in the reception of the OPERA result by the physics community. Those experiments did not detect statistically significant deviations of neutrino speeds from the speed of light. It was the closest observed supernova to Earth in more than three centuries, and the neutrinos that arrived from it came in a burst lasting about ~10 seconds: equivalent to the time that neutrinos are expected to be produced. After all, this isnt the first report of improbably speedy neutrinos. The OPERA team later discovered a faulty piece of equipment (a cable) was responsible for the timing mismatch. Is the wave-particle duality a real duality? According to Dr. Phil Plait, there's a rumour that it's been a faulty connection. The results of the neutrino experiment shook the world of physics The head of an experiment that appeared to show subatomic particles travelling faster than the speed Its a fascinating question. Virtually every physicist interviewed strongly doubts the results will hold up, including the experimenters themselves. First off, they cannot be zero. When a nucleus experiences a double neutron decay, two electrons and two neutrinos get emitted [+] conventionally. I can assure you that the OPERA people are acutely and painfully aware of the long history of highly "significant" bumps just going away. If you're going to measure speed (distance / time), you have to get the distance and time both from the same reference frame. Neutrino Faster Than Light Propulsion, not it is also unlikely that the light speed has been measured incorreclty so far. Read again what i wrote, This probably should be a comment. The GERDA experiment, a decade ago, placed the strongest constraints on neutrinoless double beta [+] decay at the time. But archaeology is confirming that Persia's engineering triumph was real. Is climate change killing Australian wine? E.g., the delay in the 8.3-km optical fiber has been measured both by two-way timing and using a portable clock, and it's been measured repeatedly over time so that one can rule out changes in optical properties due to aging of the plastic. Opinions expressed by Forbes Contributors are their own. In summary: nothing is wrong with the calculation, the theoretical assumptions, rotation of the Earth, etc A hardware problem caused the 60 ns time gap. As an experimentalist I don't begrudge the OPERA guys their error at all. Those bunches lasted 10 millionths of a second - 160 times longer than the discrepancy the team initially reported in the neutrinos' travel time. Instead of seeing it move away from you, youd see it move towards you. Thanks for making a community wiki reply. There's no complicated theoretical analysis that needs to be done to determine whether the speed of light was exceeded. But we cant really do that in practice. Whatever you are using as a timing signal, that has to travel down the cables to your computer and when you are talking about nanoseconds, you have to know exactly how quickly the current travels, and it is not instantaneous. Until theres a revolutionary new technology or experimental technique, this will, however unfortunate it is, continue to be the case. But at this point nobody sober would be willing to say that this is right., Questions or comments on this article? Heres where the disconnect between theory and experiment lies. [1]. level 2. If a systematic error enters there though, the fact of the precision of measurement with GPS, not disputed, would be a demonstration of the difference between accuracy and precision. intrinsic angular momentum exhibits either clockwise or counterclockwise spin, corresponding to whether the particle in question is a neutrino or antineutrino. In other words, the more energy your neutrino has, the more likely it is to interact with you. My answer is only a "would-be" consideration that, if read by the experimenters, could give them some "debug" clues. According their calculations, theres only a one in a billion chance that what theyre seeing is a statistical fluke. All experimental measures of |v-c|/c are within this limit. [+] It was the closest observed supernova to Earth in more than three centuries, and the neutrinos that arrived from it came in a burst lasting about ~10 seconds: equivalent to the time that neutrinos are expected to be produced. Please be respectful of copyright. All neutrinos always have a left-handed spin; all anti-neutrinos always have a right-handed spin. Do neutrinos travel faster than the speed of light? It would mean that the antineutrino emitted by one nucleus could, hypothetically, be absorbed (as a neutrino) by the other nucleus, and youd be able to get a decay where: There are currently multiple experiments, including the MAJORANA experiment, looking specifically for this neutrinoless double beta decay. I suppose an explanation along these lines would mean interesting new particle physics.