Neutrinos faster than the speed of light?

Discussion in 'Physics & Math' started by Magical Realist, Nov 1, 2013.

  1. Magical Realist Valued Senior Member

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  3. Janus58 Valued Senior Member

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    Old news that has already been corrected. It turned out that a loose connection in the detecting equipment led to an error in the calculated arrival of the Neutrinos. So no FTL neutrinos after all. I just wish that media outlets were just a zealous at reporting the "never mind", as they are about the original sensational story.
     
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  5. Magical Realist Valued Senior Member

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    Gotta check those connectors. lol! Tks..
     
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  7. Arcadian Registered Member

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    Does that mean that those particles are time traveling ?
     
  8. Read-Only Valued Senior Member

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    Hardly. All it means is that the speed was measured incorrectly.
     
  9. Trapped Banned Banned

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    Wow... I remember all the fuss, hard to imagine that was back in 2011. Tempus fugit!
     
  10. Number 9 Bus Shelter Registered Member

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    Sorry for the bump but I just wanted to say I'm really happy that has been proven wrong. If that was true, the whole universe of physics would collapse.
     
  11. origin Trump is the best argument against a democracy. Valued Senior Member

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    It would? Why?
     
  12. Number 9 Bus Shelter Registered Member

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    I meant to say modern physics, sorry. If a Neutrino can, in fact, travel faster than light then the theory of relativity would be wrong. We would have to rethink space and time.

    /watch?v=9XjS4I4oQDY
     
  13. pmb Banned Banned

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    That's incorrect. There is nothing in special relativity that prevents a particle from moving faster than the speed of light. The only thing not possible is to accelerate a particle to a speed v < c to a v = c or v > c. Moving faster than c doesn't violate relativity though. There's nothing in the theory to suggest such a thing.
     
  14. pmb Banned Banned

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    First off the phrase pure energy is meaningless term in physics and should never be used. Second, it's merely assumed (i.e. a postulate) that the proper mass, m, of a photon is zero, i.e. m = 0. However experimentally all that can be said is that

    m < 10^(-51) kg

    This can be found in Classical Electrodynamics – Third Ed. by J.D. Jackson, (1998) page 7. The effects of a non-zero value of m are taken into account in what’s known as the Proca Lagrangian (aka Proca Lagrangian Density) which is found on page 600 of Jackson in Eq. (12.91). See http://en.wikipedia.org/wiki/Proca_action

    One of the modifications m has on the equations of electrodynamics is that Coulomb force no longer follows an inverse square law. The potential has the form of a Yukawa potential, i.e. Phi(r) = qe^(-mr)/r.

    That’s incorrect. Photons, regardless of the value of their proper mass, are the quanta of light so claiming that a beam of photons which have mass is not light is an error.

    That would be inconsistent with special relativity so its hardly correct to claim that it’s possible. According to special relativity what is instantaneous in one inertial frame is not instantaneous in other inertial frames. Therefore instantaneous applies to only to certain frames of reference.
     
  15. Number 9 Bus Shelter Registered Member

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    Don't tell this to me, go tell this to Michio Kaku in the video I linked in my previous post.

    Also, Einstein himself said that nothing can go faster than light. One of his headaches was that thing called quantum entanglement, which can send information faster than light
     
  16. pmb Banned Banned

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    In the first place my speakers don't work so I wouldn't be able to hear what he's saying. In the second place I’m explaining that he’s wrong and that the information given in this thread as a result is wrong.
    In the third place I was referring to your assertion that If a Neutrino can, in fact, travel faster than light then the theory of relativity would be wrong. Not the video. And I tried that link. It gave me an error.
    However if that's what he claims then he's wrong too. Quantum entanglement cannot be used to send information. If he said he can then I'd be very surprised. If he did, then shame on him.

    And he was wrong. Although at the time he said it he was logically correct. In his relativity paper Einstein proved that it would take an infinite amount of energy to accelerate a particle to the speed of light, and that’s most certainly true even today. It was for that reason he said that Velocities greater than that of light have ... no possibility of existence. However the field of relativistic quantum mechanics didn't come into existence until several decades later. In relativistic quantum mechanics its known that particles can be created which are already moving so it wasn't required to accelerate them to such speeds. It was for this reason that Feinberg postulated the existence of tachyons, i.e. particles which are born traveling faster than the speed of light.

    In the paper where tachyons were Feinberg postulated the existence of tachyons, i.e. Possibility of Faster-Than-Light Particles, (1967), Physical Review, 159 (5): 1089–1105, (which you can download at http://www.relativitycalculator.com/images/superluminal_velocities/possibility_faster_than_light) Feinberg wrote
     
  17. brucep Valued Senior Member

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    Even if the result was confirmed it wouldn't make much difference to the usefulness of relativistic theory. Maybe the comic book version of relativity theory might be in trouble. Maybe the TV version could be in trouble. The unfortunate thing about the experiment conducted at CERN is the science teams 'monumental wood' couldn't be contained leading to the announcement of a multitude of bogus results and some job loss associated with how the experiment was conducted including spilling the beans to the media before confirmation. Deviations from the scientific method can be painful for the deviant [lol]. The relativistic limit is no information can be transferred faster than the speed of light. In the link look at #5 applet phase velocity and group velocity. Click on 'instructions' where they do a great job of explaining what each velocity represents.

    http://www-ee.eng.hawaii.edu/~zqyun/caevp.html
    Scroll down to the instructions page for this comment
    "It is known that the phase velocity can be greater than the speed of light in free space
    without violating the rule of Einstein’s theory of relativity: ‘nothing can travel at a speed
    greater than light.’ The reason is that the phase velocity does not represent the signal or
    energy velocity."

    The question becomes can a message be sent faster than the speed of light or can a particle with invariant mass be accelerated to/beyond the speed of light. The answer remains 'no' but folks are continuing to test the limits.

    Have a good one.
     
  18. Number 9 Bus Shelter Registered Member

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    That video is very recent, the guy has a PhD in physics. So... it is very unlikely that he is wrong, dude.

    oh you should get your speakers fixed btw
     
  19. pmb Banned Banned

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    A person is not right merely because they have a PhD. You'd be amazed at some of the errors people with PhDs make. And, dude, I'm no slouch either. I have the same exact level of education in quantum mechanics that he does, i.e. I also took the graduate level quantum mechanics course sequence when I as in graduate school. I'm telling you that he's wrong. It's not a guess. It's something I know. Information cannot be encoded using quantum entanglement. No information can be transmitted that way.

    See http://en.wikipedia.org/wiki/No-communication_theorem
    Now unless you're prepared to prove this theorem wrong let's move on.




    I'm getting a new system and am waiting for that to come in.
     
  20. Number 9 Bus Shelter Registered Member

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    I didn't know you had a PhD as well. Well then, that is really confusing. It seems that no one knows for sure what is known and what is not. I'm pretty sure both of you would agree that, for example, objects with heat emit radiation, like visible light. No problem. But when it comes to quantum mechanics, you have a different opinion. It seems that people don't know what is known and proven and what is not.

    What can I say then.
     
  21. brucep Valued Senior Member

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    Kaku's videos lack rigor for the sake of not having to be precise about the physics in videos which will be watched by those who don't know the difference anyway. Or more than likely you misinterpret what he's trying to convey without any actual physics. You're wrong because you didn't have a clue going in and are the main reason he can't show you the actual physics.
     
  22. pmb Banned Banned

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    I didn't say that I had a PhD. I said I have the same education in quantum mechanics than someone with a PhD in physics. That doesn't mean I have the same over all education in all areas of physics as someone with a PhD. I also don't have the same education in the other areas of theoretical physics related to quantum mechanics such as quantum field theory and relativistic quantum mechanics etc. I went to grad school for two years at night before I had to stop due to an illness in my family. However that didn't mean that I stopped learning physics. My physicist friends, all of whom have PhDs, tell me that I have the equivalence of an MS in physics if one takes my education and experience into account. Many of my friends and acquaintances have written textbooks in physics. One of them wrote the quantum mechanics textbook that’s used at MIT. I’ve discussed this subject with him before and have learned about this particular subject many times. I know what I’m talking about on this point.

    You can't just say that because someone has a PhD that means that they're right and the guy without the PhD is wrong. I know my physics very well. In fact those physicist friends gave me wonderful recommendations when I applied to a local community college to tutor math and physics.

    There’s nothing confusing here. Kaku didn’t put that in any textbook, that’s for certain. I showed you the theorem that proves that it can’t be done too. I’m certain Kaku knows this too. I’ll write to him and see why he said what he did.
     
  23. pmb Banned Banned

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    Hold on. I confused what you said about Kaku with what Nick_Hosein said about FTL communication. What exactly is it that Kaku said that you're referring to?
     

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