Page 6 of 8 FirstFirst ... 45678 LastLast
Results 51 to 60 of 75

Thread: Second experiment confirms neutrinos travel faster than light

  1. #51
    Sage

    Join Date
    Feb 2011
    Last Seen
    10-10-16 @ 10:59 AM
    Gender
    Lean
    Libertarian
    Posts
    6,073

    Re: Second experiment confirms neutrinos travel faster than light

    Quote Originally Posted by Kandahar View Post
    Not to mention that if neutrinos can travel faster than light, then so can macroscopic objects. If information can be sent faster than light, it opens the door to instantaneous teleportation across the universe. You could scan the position of every atom in your body, then step into a machine that would kill you, instantly transmit the information about your atomic composition to a receiver device on a distant world, and be reassembled by the receiver on that world.

    I have no idea what THAT would do to causality (or if relativity would even apply in such a bizarre situation) but it would certainly result in a lot of weirdness.
    My intuitive hunch is that the lighter something is, the more easy it is to make it cross the warp barrier. And since neutrinos have almost no mass, . . .

  2. #52
    Enemy Combatant
    Kandahar's Avatar
    Join Date
    Jul 2005
    Location
    Washington, DC
    Last Seen
    10-15-13 @ 08:47 PM
    Gender
    Lean
    Liberal
    Posts
    20,688

    Re: Second experiment confirms neutrinos travel faster than light

    Quote Originally Posted by solletica View Post
    I find it hard to believe that neutrinos, given their small extremely small mass, behave like little tennis balls even at near-light velocities. They should behave more like wave packets (i. e. photons or low energy electrons).
    They behave like both. Photons, electrons, and neutrinos all behave like waves AND particles. But neither waves nor particles should be able to exceed the speed of light.
    Are you coming to bed?
    I can't. This is important.
    What?
    Someone is WRONG on the internet! -XKCD

  3. #53
    Enemy Combatant
    Kandahar's Avatar
    Join Date
    Jul 2005
    Location
    Washington, DC
    Last Seen
    10-15-13 @ 08:47 PM
    Gender
    Lean
    Liberal
    Posts
    20,688

    Re: Second experiment confirms neutrinos travel faster than light

    Quote Originally Posted by solletica View Post
    My intuitive hunch is that the lighter something is, the more easy it is to make it cross the warp barrier. And since neutrinos have almost no mass, . . .
    Their mass shouldn't really matter (other than the fact that they have mass at all), because relativity indicates that as massive objects approach the speed of light, their mass approaches infinity. Since force equals mass times acceleration, it should be impossible to accelerate any particle beyond the speed of light because it would require an infinite amount of force.
    Are you coming to bed?
    I can't. This is important.
    What?
    Someone is WRONG on the internet! -XKCD

  4. #54
    Sage
    samsmart's Avatar
    Join Date
    Dec 2009
    Last Seen
    @
    Gender
    Lean
    Other
    Posts
    10,316
    Blog Entries
    37

    Re: Second experiment confirms neutrinos travel faster than light

    Quote Originally Posted by Kandahar View Post
    Possibly. But there is nothing in the known laws of physics to indicate that that would be the case. What especially interests me about this experiment is that even though the neutrinos supposedly exceeded the speed of light, they just barely exceeded it (a very small fraction of a percent). But once we've crossed that barrier there is theoretically no reason they couldn't travel much faster...at an arbitrarily fast speed.
    Okay. Very good points. But we don't know what properties of the neutrinos allow it to go FTL. So while it brings up a whole lot of options, it also means we don't know what options are closed to us.

    Quote Originally Posted by Kandahar View Post
    I don't see how (which isn't necessarily to say that it's impossible). Special relativity indicates that the laws of physics should look the same to everyone, regardless of their frame of reference. If neutrinos can travel faster than light, that means that it should be possible to send information faster than light. For example, if you stand on Earth and I stand on Betelgeuse and we fire beams of superluminal neutrinos at each other in Morse Code, we could communicate instantly even though we were 640 light-years apart.
    I can see that it would be potentially possible for instantaneous communication. But aren't there practical limits? For example, if I can send a signal twice the speed of light wouldn't that mean that my Morse Code signal from Earth only get to Betelgeuse in 320 years instead of 640?

    I mean as you say these neutrinos seemed to only go a very small percentage faster than light. But shouldn't there be a difference between someone being able to go a small percentage faster than c and someone being able to go a large percentage faster than c?

    Quote Originally Posted by Kandahar View Post
    And being able to send information faster-than-light DOES have serious repercussions for causality. For example, suppose I've rigged up a series of Christmas lights in a straight line across our section of the galaxy. I've set them up so that I'll send a superluminal neutrino signal to Light 1, which will then turn itself on and send a superluminal signal to Light 2 to do the same, etc. If you're in a spaceship traveling at near the speed of light in the same direction as my superluminal neutrino signal, from your perspective you would see Light 2 turn itself on before Light 1 ever sent it a signal to do so! Since there is nothing special about my frame of reference, I can't say that my interpretation of causality is correct and yours is wrong. You would have witnessed an effect happening before its cause, and your perception of the events would be just as valid as mine.
    Okay. So wouldn't that mean that being able to go FTL would only put us at a higher dimension of time?

    I once had a friend try to explain how dimensions would seem to entities from a different dimension. My friend explained to me how a 2-dimensional being would perceive a 3-dimensional cone. If it would travel from the point of the cone to the base, it would only see a point that got larger and larger and larger until it became a circle the circumference of the base of the cone.

    So maybe with FTL we would be able to go to the next dimension of time. Effectively, people in 1-dimensional time would face the repercussions of manipulated causality but people in 2-dimensional time would witness that event linearly.
    Also, we need to legalize recreational drugs and prostitution.

  5. #55
    Enemy Combatant
    Kandahar's Avatar
    Join Date
    Jul 2005
    Location
    Washington, DC
    Last Seen
    10-15-13 @ 08:47 PM
    Gender
    Lean
    Liberal
    Posts
    20,688

    Re: Second experiment confirms neutrinos travel faster than light

    Quote Originally Posted by samsmart View Post
    Okay. Very good points. But we don't know what properties of the neutrinos allow it to go FTL. So while it brings up a whole lot of options, it also means we don't know what options are closed to us.

    I can see that it would be potentially possible for instantaneous communication. But aren't there practical limits? For example, if I can send a signal twice the speed of light wouldn't that mean that my Morse Code signal from Earth only get to Betelgeuse in 320 years instead of 640?
    The only known universal speed limit, is the speed of light. So once you have a way to break that speed limit, there isn't any additional upper bound to speed (that we know of), which means that you can send information instantaneously for all intents and purposes. If there is some speed limit that hasn't yet been discovered, which is greater than the speed of light but less than infinity, there might be practical limitations. But the same basic logic would apply, you'd just have to assume longer-lived scientists for the purposes of that thought experiment.

    I mean as you say these neutrinos seemed to only go a very small percentage faster than light. But shouldn't there be a difference between someone being able to go a small percentage faster than c and someone being able to go a large percentage faster than c?
    If there is any difference, the currently-known laws of physics do not account for it.

    Okay. So wouldn't that mean that being able to go FTL would only put us at a higher dimension of time?

    I once had a friend try to explain how dimensions would seem to entities from a different dimension. My friend explained to me how a 2-dimensional being would perceive a 3-dimensional cone. If it would travel from the point of the cone to the base, it would only see a point that got larger and larger and larger until it became a circle the circumference of the base of the cone.

    So maybe with FTL we would be able to go to the next dimension of time. Effectively, people in 1-dimensional time would face the repercussions of manipulated causality but people in 2-dimensional time would witness that event linearly.
    That is essentially accurate for how a 2-dimensional being would view the third dimension. But all prominent theories and hypotheses indicate that there is only 1 dimension of time. String theory says that our universe consists of 10 or 11 dimensions...but they are all spatial dimensions except for the 1 time dimension that we already know of. But to answer your question, yes, if neutrinos can travel faster than light it would throw open the door to time travel.
    Last edited by Kandahar; 11-21-11 at 11:15 PM.
    Are you coming to bed?
    I can't. This is important.
    What?
    Someone is WRONG on the internet! -XKCD

  6. #56
    Sage

    Join Date
    Feb 2011
    Last Seen
    10-10-16 @ 10:59 AM
    Gender
    Lean
    Libertarian
    Posts
    6,073

    Re: Second experiment confirms neutrinos travel faster than light

    Quote Originally Posted by whysoserious View Post
    Isn't it generally accepted that those types of particles behave like both?
    All masses behave like particles and waves. Doesn't matter whether it's subatomic or a bowling ball.

    However, recall the equation for the uncertainty principle. . .

    delta x * delta p >= h-bar / 2 .

    Also recall the equation for momentum. . .

    p = mv / sqrt (1 - v^2 / c^2 ),

    so when m is really big (i. e. a bowling ball), a change in p entails a very small change in v. But when m is really small (i. e. a neutrino), a change in p entails a very large change in v. So a bowling ball can have a large error for momentum and still retain its velocity, whereas a neutrino can't.

    And by the uncertainty principle equation, if delta p is big, then delta x is small. In other words, the large margin of error in the momentum allowed for a moving bowling ball ensure that it behaves more like a moving object instead of a wave packet w/the ball jumping around all over the place.

    However, when measuring the velocities of subatomic particles (i. e. neutrinos), v must be confined, or else the integrity of the experiment is compromised. This means p is allowed only a very small margin of error. But by uncertainty principle equation, if delta p is small, delta x (error in position) becomes big, which means that the neutrino will behave more like a wave packet than a moving object.

    Of course, at speeds very near that of light, a neutrino's relativistic mass will become much much larger than its rest mass, so it'll behave more like a billiard ball. But I'm curious exactly how fast these neutrinos were travelling. Was it .9999999c, .9999999999999999999999999999999c? With a neutrino, it matters! If it's velocity isn't extremely, extremely near c, it'll retain its wavelike properties, and the experiment has to account for that.

  7. #57
    Sage

    Join Date
    Feb 2011
    Last Seen
    10-10-16 @ 10:59 AM
    Gender
    Lean
    Libertarian
    Posts
    6,073

    Re: Second experiment confirms neutrinos travel faster than light

    Quote Originally Posted by Kandahar View Post
    Their mass shouldn't really matter (other than the fact that they have mass at all), because relativity indicates that as massive objects approach the speed of light, their mass approaches infinity. Since force equals mass times acceleration, it should be impossible to accelerate any particle beyond the speed of light because it would require an infinite amount of force.
    Yes, but we're talking about neutrinos. Even if the neutrino is traveling at .9999999999999c, it's still won't amount to a billionth of a feather in (relativistic) mass.

  8. #58
    Sage
    samsmart's Avatar
    Join Date
    Dec 2009
    Last Seen
    @
    Gender
    Lean
    Other
    Posts
    10,316
    Blog Entries
    37

    Re: Second experiment confirms neutrinos travel faster than light

    Quote Originally Posted by Kandahar View Post
    The only known universal speed limit, is the speed of light. So once you have a way to break that speed limit, there isn't any additional upper bound to speed (that we know of), which means that you can send information instantaneously for all intents and purposes. If there is some speed limit that hasn't yet been discovered, which is greater than the speed of light but less than infinity, there might be practical limitations. But the same basic logic would apply, you'd just have to assume longer-lived scientists for the purposes of that thought experiment.



    If there is any difference, the currently-known laws of physics do not account for it.
    So what you're saying is that physicists see no difference between "greater than c" and "infinity"?

    Quote Originally Posted by Kandahar View Post
    That is essentially accurate for how a 2-dimensional being would view the third dimension. But all prominent theories and hypotheses indicate that there is only 1 dimension of time. String theory says that our universe consists of 10 or 11 dimensions...but they are all spatial dimensions except for the 1 time dimension that we already know of. But to answer your question, yes, if neutrinos can travel faster than light it would throw open the door to time travel.
    Okay, before we go on, let me clear something up with regards to the example you gave here:

    Quote Originally Posted by Kandahar View Post
    And being able to send information faster-than-light DOES have serious repercussions for causality. For example, suppose I've rigged up a series of Christmas lights in a straight line across our section of the galaxy. I've set them up so that I'll send a superluminal neutrino signal to Light 1, which will then turn itself on and send a superluminal signal to Light 2 to do the same, etc. If you're in a spaceship traveling at near the speed of light in the same direction as my superluminal neutrino signal, from your perspective you would see Light 2 turn itself on before Light 1 ever sent it a signal to do so! Since there is nothing special about my frame of reference, I can't say that my interpretation of causality is correct and yours is wrong. You would have witnessed an effect happening before its cause, and your perception of the events would be just as valid as mine.
    1) There's a series of lights strung throughout the galaxy
    2) For the next light to turn itself on the light before must turn on first and must do so within a certain interval.
    3) If we use a subluminal signal to activate the lights, people at subluminal speeds traveling beside the lights will see Light 2 turn on at the interval after Light 1 turns on.
    4) If we use an FTL signal to activate the lights, people at subluminal speeds traveling beside the lights will see Light 2 turn on before the interval after Light 1. However, those people will still see Light 1 turn on before Light 2.
    5) If we use an FTL singal to activate the lights, people at the same FTL speed traveling beside the lights will see Light 2 turn on at the interval after Light 1 turns on.

    Are these points right?
    If they are not right, which points aren't?
    For these points that aren't, why aren't they?

    I'm not arguing with you, and I hope I'm not coming across that way. I'm just trying to understand all this stuff. :P
    Last edited by samsmart; 11-21-11 at 11:52 PM.
    Also, we need to legalize recreational drugs and prostitution.

  9. #59
    Enemy Combatant
    Kandahar's Avatar
    Join Date
    Jul 2005
    Location
    Washington, DC
    Last Seen
    10-15-13 @ 08:47 PM
    Gender
    Lean
    Liberal
    Posts
    20,688

    Re: Second experiment confirms neutrinos travel faster than light

    Quote Originally Posted by solletica View Post
    Yes, but we're talking about neutrinos. Even if the neutrino is traveling at .9999999999999c, it's still won't amount to a billionth of a feather in (relativistic) mass.
    But we aren't talking about neutrinos traveling at .9999999999999c. These neutrinos (allegedly) exceeded the speed of light, which is substantially different. If you put enough 9s on that decimal, eventually that neutrino will be as massive as the entire universe. It cannot exceed the speed of light because an infinite mass would require an infinite force to accelerate it further.
    Are you coming to bed?
    I can't. This is important.
    What?
    Someone is WRONG on the internet! -XKCD

  10. #60
    Banned
    Join Date
    May 2011
    Location
    Huntsville, AL
    Last Seen
    03-03-17 @ 10:28 AM
    Gender
    Lean
    Conservative
    Posts
    13,813

    Re: Second experiment confirms neutrinos travel faster than light

    Quote Originally Posted by Boring Bob View Post
    This isn't a criticism, but a mere question to help me understand the concept. Is speed not relative? It seems to me that light itself would exceed C if the frame of reference were also moving in the opposite direction of that light, or at least would be measured to be higher. I always thought of C as a speed with the reference point being space itself (the grid points of the universe if you will), though maybe I'm missing some ideas from relativity. If the Earth were to move in the opposite direction of light through space, couldn't an observer then measure the speed of light to be higher than C relative to the earth?
    Time and space...if relativity be real than physics must work (assuming uniform motion) in any frame of reference. No frame of reference can be superior to any other. This is difficult. It always has been.

Page 6 of 8 FirstFirst ... 45678 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •