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Big story ....CERN scientists break the speed of light

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Comments

  • Closed Accounts Posts: 6,556 ✭✭✭the_monkey


    Wow !!! , Can't wait for the religious fools on this - Einstein was wrong => the Bible is correct - well i'm convinced .... :rolleyes:


  • Registered Users, Registered Users 2 Posts: 1,136 ✭✭✭del88


    the_monkey wrote: »
    Wow !!! , Can't wait for the religious fools on this - Einstein was wrong => the Bible is correct - well i'm convinced .... :rolleyes:
    Maybe Jesus gave them an extra little push seems how the nutrinos were heading for rome.... he does work in mysterious ways ..


  • Closed Accounts Posts: 8,156 ✭✭✭Iwannahurl


    Upper limit on speed:
    If the spatial distance between two events A and B is greater than the time interval between them multiplied by c then there are frames of reference in which A precedes B, others in which B precedes A, and others in which they are simultaneous. As a result, if something were travelling faster than c relative to an inertial frame of reference, it would be travelling backwards in time relative to another frame, and causality would be violated. In such a frame of reference, an "effect" could be observed before its "cause". Such a violation of causality has never been recorded, and would lead to paradoxes such as the tachyonic antitelephone.
    So now you know.


  • Registered Users, Registered Users 2 Posts: 784 ✭✭✭thecornflake


    Iwannahurl wrote: »
    Upper limit on speed:
    If the spatial distance between two events A and B is greater than the time interval between them multiplied by c then there are frames of reference in which A precedes B, others in which B precedes A, and others in which they are simultaneous. As a result, if something were travelling faster than c relative to an inertial frame of reference, it would be travelling backwards in time relative to another frame, and causality would be violated. In such a frame of reference, an "effect" could be observed before its "cause". Such a violation of causality has never been recorded, and would lead to paradoxes such as the tachyonic antitelephone.
    So now you know.

    Grand, i just derived all my formulae for my new theorem from the results of the experiment that will be performed next week.


  • Closed Accounts Posts: 5,132 ✭✭✭Killer Pigeon


    So, does this mean all the Relativity and Quantum Mechanics courses I'm taking this year are utterly pointless?


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  • Closed Accounts Posts: 1,345 ✭✭✭The Dagda


    So, does this mean all the Relativity and Quantum Mechanics courses I'm taking this year are utterly pointless?


    Unforetunately it does, but the good news is, you can now go back and do something else. It's an ill wind...


  • Registered Users, Registered Users 2 Posts: 861 ✭✭✭Professor_Fink


    The Dagda wrote: »
    Unforetunately it does, but the good news is, you can now go back and do something else. It's an ill wind...

    No it doesn't. Superluminal particles aren't specifically forbidden by either quantum mechanics or relativity, but we've never seen them, and they present so many paradoxes we never believed they could actually exist. However, they can present difficulties with formulating field theories.

    Also, the experiment is probably wrong.


  • Registered Users, Registered Users 2 Posts: 500 ✭✭✭parrai


    So say it's true, (or fair enough, they have said it's true) what are the practical/potential uses for this break through?


  • Moderators, Science, Health & Environment Moderators Posts: 23,243 Mod ✭✭✭✭godtabh


    .

    Also, the experiment is probably wrong.

    Why do you say that?


  • Registered Users, Registered Users 2 Posts: 151 ✭✭Anonymo


    No it doesn't. Tachyons aren't specifically forbidden by either quantum mechanics or relativity, but we've never seen them, and they present so many paradoxes we never believed they could actually exist. However, they can present difficulties with formulating field theories.

    Also, the experiment is probably wrong.

    Just a couple of comments on this. Firstly, these are not necessarily tachyons. Though tachyons are the general name to things moving at greater than the speed of light, this discovery might not actually be saying anything about the speed of light. Instead it may be an indication that there are extra dimensions (offering a shorter path to the neutrinos). Tachyons are, as you mention, generally looked on as a sign of instability and it is the desire to avoid them, for instance, that limits the number of string theory dimensions to 10.

    Your last claim that 'the experiment is probably wrong' could do with some explanation. The CERN guys are generally very careful. It could be that some systematic error has not been accounted for. That I would agree with, but not your statement.


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  • Registered Users, Registered Users 2 Posts: 6,854 ✭✭✭zuutroy


    What hasn't been mentioned is that the effect of doing the experiment in air. It's the speed of light in a vacuum that's the universal constant. Would like to see this addressed.


  • Closed Accounts Posts: 5,132 ✭✭✭Killer Pigeon


    Also, the experiment is probably wrong.

    It's either wrong or just sensationised.


  • Registered Users, Registered Users 2 Posts: 151 ✭✭Anonymo


    zuutroy wrote: »
    What hasn't been mentioned is that the effect of doing the experiment in air. It's the speed of light in a vacuum that's the universal constant. Would like to see this addressed.

    Agree completely with this. However, they have calculated the result based on the speed of light in a vacuum. The speed of light through other media will presumably move at a lower velocity making the problem even worse. Nonetheless, this is just an assumption that I'm making and, like you, would like to see it addressed.


  • Closed Accounts Posts: 3,619 ✭✭✭fontanalis


    Was there an idea of somethign called inflation put forward years ago that claimed the expansion after the big bang may have travelled faster than light?


  • Registered Users, Registered Users 2 Posts: 151 ✭✭Anonymo


    fontanalis wrote: »
    Was there an idea of somethign called inflation put forward years ago that claimed the expansion after the big bang may have travelled faster than light?

    In that case no information was moving faster than light. What was happening was that the fabric of spacetime itself was inflated (akin to inflating a balloon) and objects in the spacetime (like dots on the balloon) moved apart at faster than the speed of light. No information was transmitted between points. This is a fundamental difference.

    The paradigm of inflation is quite widely accepted in cosmology. It is used to explain the fact that the temperature of the universe is so uniform, which couldn't have been the case unless there was a period of such rapid expansion in the early universe (unless some very exotic scenario is invoked).


  • Registered Users, Registered Users 2 Posts: 861 ✭✭✭Professor_Fink


    Anonymo wrote: »
    Your last claim that 'the experiment is probably wrong' could do with some explanation. The CERN guys are generally very careful. It could be that some systematic error has not been accounted for. That I would agree with, but not your statement.

    Even they don't believe it, which is why they haven't claimed it as a discovery (despite the 6.1\sigma gap). Literally everyone I talked to today thought it was probably some form of unaccounted for systematic error. I literally don't know a single physicist willing to take an even money bet in favour of this.

    Of course they are careful, which is what makes the story worth paying attention to, but as far as I can see the general feeling is that this will turn out like the pioneer anomaly.


  • Registered Users, Registered Users 2 Posts: 861 ✭✭✭Professor_Fink


    It's either wrong or just sensationised.

    Nope. If it's correct it is the most important experimental result in nearly 100 years.


  • Registered Users, Registered Users 2 Posts: 861 ✭✭✭Professor_Fink


    zuutroy wrote: »
    What hasn't been mentioned is that the effect of doing the experiment in air. It's the speed of light in a vacuum that's the universal constant. Would like to see this addressed.

    Seriously? You think this passed vetting at CERN with that kind of elementary error?


  • Registered Users, Registered Users 2 Posts: 861 ✭✭✭Professor_Fink


    Anonymo wrote: »
    ...it is the desire to avoid them, for instance, that limits the number of string theory dimensions to 10.

    Really? The only proof I know is for bosonic string theory, but it is based on the differing number of spin eigenstates for massive and massless particles of fixed spin, and not on ruling out tachyons.


  • Registered Users, Registered Users 2 Posts: 151 ✭✭Anonymo


    Really? The only proof I know is for bosonic string theory, but it is based on the differing number of spin eigenstates for massive and massless particles of fixed spin, and not on ruling out tachyons.

    To an extent I'm being a bit loose with this. By adding fermions to the theory the superstring theory will then have ghosts in the fermionic sector as well as the usual ghost (tachyon) state from the bosonic sector. Eliminating the ghosts in the fermionic sector fixes the spacetime dimension to be 10 which also eliminates the tachyon.


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  • Registered Users, Registered Users 2 Posts: 7,237 ✭✭✭mcmoustache


    Does this not contradict what was observed when SN1987A exploded. Then neutrinos were detected only hours earlier, if even that, than the photons.

    If the CERN experiment was kosher, then the gap between neutrino and photon detection in the supernova event above would have been in the order of years and not hours as was observed*.

    *60 nano seconds in 2 milliseconds means 60/2000000 = 0.00003. It means that the gap is .003%. The supernova was 160,000 light years away so the gap would have been about 5 years. It wasn't.

    **(Info pulled from a slashdot post and not all my own work)


  • Registered Users, Registered Users 2 Posts: 151 ✭✭Anonymo


    Does this not contradict what was observed when SN1987A exploded. Then neutrinos were detected only hours earlier, if even that, than the photons.

    If the CERN experiment was kosher, then the gap between neutrino and photon detection in the supernova event above would have been in the order of years and not hours as was observed*.

    *60 nano seconds in 2 milliseconds means 60/2000000 = 0.00003. It means that the gap is .003%. The supernova was 160,000 light years away so the gap would have been about 5 years. It wasn't.

    **(Info pulled from a slashdot post and not all my own work)

    Yep and this is probably the main reason that the result is not believed. The main systematic must be something to do with the distance measurement. For the supernova measurement neutrinos are compared directly to photons. The reason photons arrive later is because they are scattering off each other - they are moving faster than the neutrinos but the neutrinos are moving freely. The issue with this experiment is that photons cannot pass through mountains! So the neutrino speed must be calculated by knowing the distance extremely accurately.


  • Registered Users, Registered Users 2 Posts: 6,854 ✭✭✭zuutroy


    Seriously? You think this passed vetting at CERN with that kind of elementary error?

    No, just that I haven't seen it addressed anywhere. I just can't help thinking there'll be some caveat or technicality that will make it a damp squib.


  • Registered Users, Registered Users 2 Posts: 861 ✭✭✭Professor_Fink


    zuutroy wrote: »
    No, just that I haven't seen it addressed anywhere. I just can't help thinking there'll be some caveat or technicality that will make it a damp squib.

    Then watch the webcast. They've been through the entire experiment and timing procedure in detail.


  • Closed Accounts Posts: 8,156 ✭✭✭Iwannahurl


    Nope. If it's correct it is the most important experimental result in nearly 100 years.



    Fair enough, we assume this new finding is provisional until replicated. And replicated more than once, presumably, given the maxim that extraordinary claims require extraordinary proofs.

    The hypothesis that neutrinos are faster than light has been around for a while, it seems.

    So this is the first convincing observation that it might be true?

    May I ask you to speculate, in layman's language that I can understand, what the implications of this discovery might be, if it is shown to be a real phenomenon?

    Might it help to solve one or two of the unsolved problems in Physics, for example?


  • Registered Users, Registered Users 2 Posts: 861 ✭✭✭Professor_Fink


    Anonymo wrote: »
    Yep and this is probably the main reason that the result is not believed.

    Actually, no, its not a contradiction. The supernova data is for energies centred on 10MeV where as the OPERA result is for 17GeV, which is a huge difference. There have been proposed models where the velocity is energy dependent, and the current results support that.

    On the other hand, you are right that it is held up as a reason not to believe the current results.


  • Registered Users, Registered Users 2 Posts: 26,578 ✭✭✭✭Turtwig


    Just for some lulz.:D

    neutrinos.png


  • Closed Accounts Posts: 2,616 ✭✭✭FISMA


    No it doesn't. Superluminal particles aren't specifically forbidden by either quantum mechanics or relativity...
    +1
    Also, the experiment is probably wrong.
    +1

    Agreed.

    First, Einstein said no [material] thing, that is of matter, can go the speed of light or faster. If you read Einstein's works, you'll see that he held out the possibility of a superluminal realm. One where greater than lights speeds were possible. The only caveat being that we would not be able to sense/perceive such a realm.

    Kudos to the people at Cern and I hope that their results are independently verified. However, until such time as they are, I'll keep the cork on the Champagne...


  • Registered Users, Registered Users 2 Posts: 122 ✭✭GenghisCon


    A lament for C, as sung by an Irish bachelor farmer.

    Sung to the air of “The sea around us” by Dominic Behan

    My mind it is troubled as I set out on my toil.
    With spade and with hoe I attend to the soil.
    But news I’ve received has shook me to my core,
    Relativity it seems may be special no more.

    (chorus)
    The C oh the C, is grá geal mo chroi!
    You were immutable or so it appeared to me…
    But now it would seem you’re as fickle as could be,
    and neutrinos may even be swifter than thee?

    If neutrinos have mass but can beat light to the punch…
    …what does it mean for E = MC such n such ?
    But if neutrinos change state can they skip forward in time…
    and not be the same particle that crosses the finish line?


    (chorus)

    If the ether is dense, light may even twist a wee bit.
    If space time was flat a neutrino wouldn't win in a fit.
    Could it be that the limit and light’s speed are not one and the same…
    and that neutrino and anti-neutrinos are just arbitrary names?


    (chorus)

    But what do I know? this matters not one jot.
    There’s more spuds to be set as I bemoan my lot.
    My sheepdog’s got pleurisy, we’ve got more bugs than bed,
    and from the smell of that box, Schrödinger’s cat is certainly dead.

    (chorus)


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  • Registered Users, Registered Users 2 Posts: 1,792 ✭✭✭Gandalph


    It was only a matter of time, Usain Bolt came close to beating the speed of light in training one day.


  • Closed Accounts Posts: 3 dapperdon


    Gandalph wrote: »
    It was only a matter of time, Usain Bolt came close to beating the speed of light in training one day.

    I wonder was the particle tested for performance enhancing substances when it did a Ben Johnson ?.

    I think this will prove to be instrumentation error or similar, i saw it said that it was only a few meters per second faster then the speed of light, you have to wonder why such a tiny increase when you would think vastly faster then light speeds would be just as possible once it had broken light speed.

    Cant help thinking its another "cold fusion" hoopla.


  • Registered Users, Registered Users 2 Posts: 28 AIDO Tours


    zuutroy wrote: »
    What hasn't been mentioned is that the effect of doing the experiment in air. It's the speed of light in a vacuum that's the universal constant. Would like to see this addressed.


    the experiment wasn't done in air, it was done in rock. Sound travels faster through a more dense medium so why shouldn't Light?


  • Closed Accounts Posts: 8,156 ✭✭✭Iwannahurl


    If it is an error or a false alarm, I doubt very much that's it's in the Cold Fusion category.

    Is it not the case that Neutrinos/Tachyons have been the subject of very serious scientific study for decades?

    In terms of the process of scientific research, nothing unusual is going on. It's just that this particular finding is generating a lot of general interest, excitement, speculation and media coverage.

    And why not? All the better to stimulate people's interest in science, especially the young aspiring physicists.


  • Closed Accounts Posts: 8,156 ✭✭✭Iwannahurl


    MIT physicist Peter Fisher answers questions about reports that experiments in Switzerland and Italy show neutrinos can break light’s speed limit.


    Q. If this turns out to be some kind of unrecognized systematic error in the measurements, would that reflect badly on the scientists who reported it, or would it just be a reflection of science working as it’s supposed to?

    A. I would say more the latter. I know a number of the people on the OPERA experiment [at Gran Sasso] and they are very thoughtful, careful people who would never publish a result like this unless they were certain there was no better explanation. I would bet that whatever the explanation is, it will be very interesting.




    http://web.mit.edu/newsoffice/2011/3q-fisher-neutrinos-opera.html


  • Registered Users, Registered Users 2 Posts: 6,854 ✭✭✭zuutroy


    AIDO Tours wrote: »
    the experiment wasn't done in air, it was done in rock. Sound travels faster through a more dense medium so why shouldn't Light?

    Because they have totally different means of propagation.


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  • Registered Users, Registered Users 2 Posts: 28 AIDO Tours


    zuutroy wrote: »
    Because they have totally different means of propagation.


    I disagree with the word totally. Different yes but totally no, they both are propagated as waves, or at least when I was in UCC up to 1999 that was the case


  • Registered Users, Registered Users 2 Posts: 6,854 ✭✭✭zuutroy


    AIDO Tours wrote: »
    I disagree with the word totally. Different yes but totally no, they both are propagated as waves, or at least when I was in UCC up to 1999 that was the case

    Sound is transferred through the vibration of matter. Light is transferred through electromagnetic waves/photons and has no need for matter to propagate. The only thing they have in common is that they're waves, but of completely different types (and in light's case it isn't even a wave a lot of the time!)
    Sound travels faster through denser materials because the atoms are packed closely together. Light generally travels slower through matter due to localised disturbances in the electric field of the atoms caused by the electromagnetic wave.


  • Closed Accounts Posts: 130 ✭✭Kohl


    I'm no physicist, but could the neutrinos possibly have come from somewhere else?


  • Closed Accounts Posts: 206 ✭✭okeanes


    the paticals that are moving faster than light , how are they moving ?

    does this change anything , and what about science teachers will they have to do a coarse to fully understand this and teach correctly to students .


  • Registered Users, Registered Users 2 Posts: 28 AIDO Tours


    zuutroy wrote: »
    Sound is transferred through the vibration of matter. Light is transferred through electromagnetic waves/photons and has no need for matter to propagate........
    Sound travels faster through denser materials .... Light generally travels slower......


    I still disagree with the word totally :) otherwise you are 100% correct.

    It is too long since I studied this stuff and longer again since I made use of it


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  • Registered Users, Registered Users 2 Posts: 31 Ghost_of_ED209


    Come on.... We all know this was Chuck Norris... He roundhouse kicked someone so hard that his foot broke the speed of light.


  • Moderators, Sports Moderators Posts: 28,114 Mod ✭✭✭✭Podge_irl


    AIDO Tours wrote: »
    I disagree with the word totally. Different yes but totally no, they both are propagated as waves, or at least when I was in UCC up to 1999 that was the case

    They're really not comparable.

    On a very simplistic level they both propagate as waves but to deal with light properly you have to delve into wave packets and quantisation. The mechanisms behind them are almost completely different.
    the paticals that are moving faster than light , how are they moving ?

    Glib answer - they're probably not moving faster then light. If it turns out they were (which I could almost guarantee it won't), then we wouldn't know.


  • Closed Accounts Posts: 2,207 ✭✭✭longhalloween


    Look, chances are everything we know about the universe is wrong and will be proven wrong at some point.

    But right now the models work and all this will simply further our knowledge. It's a good thing that Einstein was proven wrong, because if our knowledge about physics peaked in the 1940's that would be kinda sad.


  • Moderators, Sports Moderators Posts: 28,114 Mod ✭✭✭✭Podge_irl


    Look, chances are everything we know about the universe is wrong and will be proven wrong at some point.

    That's not even remotely true. Things will undoubtedly be refined somewhat, but to call it "wrong" would be incredibly unfair and essentially inaccurate.
    It's a good thing that Einstein was proven wrong, because if our knowledge about physics peaked in the 1940's that would be kinda sad.

    He hasn't been proven wrong. Nor did he think that GR was the be all and end all. He dedicated quite a large part of his later life to trying to reconcile it with QM but ultimately failed. But if GR was wrong then we wouldn't have GPS amongst many other things.


  • Closed Accounts Posts: 29 Giuseppe55


    How did they detect the neutrinos, anyway? My understanding is that neutrinos practically never interact with any other particles.


  • Registered Users, Registered Users 2 Posts: 1,792 ✭✭✭Gandalph


    Its no coincidence Jurrasic Park is back in the cinema lads! We are officially time travellers!


  • Closed Accounts Posts: 3,619 ✭✭✭fontanalis


    The barman says, sorry we don't serve time travelers.
    Two time travelers walk into a bar.


  • Closed Accounts Posts: 8,156 ✭✭✭Iwannahurl


    I was into the Neutrinos before they arrived.


  • Closed Accounts Posts: 8,156 ✭✭✭Iwannahurl


    A neutrino walks into a bar.

    And doesn't stop.


  • Closed Accounts Posts: 8,156 ✭✭✭Iwannahurl


    Neutrino.

    Who's there?

    Knock knock.


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