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Thread: Neutrinos and antineutrinos

  1. #1 Neutrinos and antineutrinos 
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    What differs neutrino from the antineutrino? Neutrinos are almost massless and lack an electric charce, so what could make them different?


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    Forum Masters Degree bit4bit's Avatar
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    Opposite/different quantum 'spins'?


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    The Doctor Quantime's Avatar
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    I'll have a loook.

    There are three types of neutrinos. Electron, muon and tau.

    Electron = <50eV?
    Muon = <0.5MeV
    Tau = <70MeV?

    The only properties of the neutrino is Mass in GeV/c^2 which is what the figures are next to them. So there would only be antimass.
    "If you wish to make an apple pie from scratch, you must first invent the universe". - Carl Sagan
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  5. #4  
    Moderator Moderator AlexP's Avatar
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    Quote Originally Posted by bit4bit
    Opposite/different quantum 'spins'?
    They can have the same spin, that's not it.

    Quote Originally Posted by svwillmer
    The only properties of the neutrino is Mass in GeV/c^2 which is what the figures are next to them. So there would only be antimass.
    That's not it either, sorry... There's a property of particles called helicity. The helicity of a particle is described as being either "left-handed" or "right-handed." It has to do with the direction of spin in regard to the direction of momentum. A neutrino and an antineutrino are the same thing, except that they have opposite helicity.
    "There is a kind of lazy pleasure in useless and out-of-the-way erudition." -Jorge Luis Borges
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  6. #5 Re: Neutrinos and antineutrinos 
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    Quote Originally Posted by Elina
    What differs neutrino from the antineutrino? Neutrinos are almost massless and lack an electric charce, so what could make them different?
    See what chemboy said.

    Here's a way to visualize it. See this bullwhip?



    Imagine cracking the bullwhip; imagine that loop running down the length of the bullwhip until it gets to the end: Crack!

    Now imagine it running the other way. Or in other words again: what's different about the neutrino and the antineutrino is the direction of the action turn compared to the direction of propagation.
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    Forum Ph.D. Steve Miller's Avatar
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    Hello Farsight!

    I don't understand you last sentence. The end of the sentence the least.

    Or in other words again: what's different about the neutrino and the antineutrino is the direction of the action turn compared to the direction of propagation.
    Does that mean the whip running backwards from the actual crack to the moment
    the crack was set off?

    Steve
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  8. #7  
    The Doctor Quantime's Avatar
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    Quote Originally Posted by Steve Miller
    Hello Farsight!

    I don't understand you last sentence. The end of the sentence the least.

    Or in other words again: what's different about the neutrino and the antineutrino is the direction of the action turn compared to the direction of propagation.
    Does that mean the whip running backwards from the actual crack to the moment
    the crack was set off?

    Steve
    Yes.
    "If you wish to make an apple pie from scratch, you must first invent the universe". - Carl Sagan
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  9. #8  
    Forum Ph.D. Steve Miller's Avatar
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    Quote Originally Posted by svwillmer
    Quote Originally Posted by Steve Miller
    Hello Farsight!

    I don't understand you last sentence. The end of the sentence the least.

    Or in other words again: what's different about the neutrino and the antineutrino is the direction of the action turn compared to the direction of propagation.
    Does that mean the whip running backwards from the actual crack to the moment
    the crack was set off?

    Steve
    Yes.
    Are you sure? Your are not th actual author, you'll have noticed?
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  10. #9  
    The Doctor Quantime's Avatar
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    Quote Originally Posted by Steve Miller
    Quote Originally Posted by svwillmer
    Quote Originally Posted by Steve Miller
    Hello Farsight!

    I don't understand you last sentence. The end of the sentence the least.

    Or in other words again: what's different about the neutrino and the antineutrino is the direction of the action turn compared to the direction of propagation.
    Does that mean the whip running backwards from the actual crack to the moment
    the crack was set off?

    Steve
    Yes.
    Are you sure? Your are not th actual author, you'll have noticed?
    Well think about it, momentum reversed, velocity reversed, direction reversed. It's pretty obvious; I don't have to be the author to know the answer to your question.
    "If you wish to make an apple pie from scratch, you must first invent the universe". - Carl Sagan
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  11. #10  
    Forum Ph.D. Steve Miller's Avatar
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    Hey ya svwillmer,

    you seem to know better that the actual author. So then, what was the sample good for? Watch out your stand
    cracking a bull whip? The whip will reverse the crack and flutter you away?

    Steve
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  12. #11  
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    Quote Originally Posted by Steve Miller
    Hello Farsight!

    I don't understand your last sentence. The end of the sentence the least.

    Or in other words again: what's different about the neutrino and the antineutrino is the direction of the action turn compared to the direction of propagation.
    Does that mean the whip running backwards from the actual crack to the moment the crack was set off?
    Not backwards in time. Just backwards. It's going the other way. If you've got a running loop that's turning in a clockwise direction. It can go this way O→ or this way ←O . There's nothing special about the clockwise direction. You could walk round to the other side of it and say it was turning in an anticlockwise direction. What's important is the direction of the turning action compared to the direction of propagation. One configuration is the mirror image of the other.

    The electron and positron are related in a similar fashion. Some people talk about a positron as a "time reversed electron", but it isn't. It's a mirror image of the electron. It's like your left and right hand, they have opposite "handedness" or chirality. The neutrino and antineutrino are similar, but we don't call it chirality we call it helicity, and there's no twist to keep them in place so they have no charge and they move more like a photon. You could say the photon is a transverse wave, the electron is a standing wave or soliton and the neutrino is a rolling wave, but I'm not sure that quite captures it. And I'm a bit cautious about using the word spin, because it tends to imply a "billiard ball particle" whirling like a dervish with topspin or backspin. It isn't like that. It's just action.

    A lot of people don't really know what action is. But it's quite easy when it clicks. Here's an excerpt from my paper A Qualitative 3+1 Dimensional Geometrical Model which is under review at a journal. It isn't accepted physics, but I'm confident that some significant elements of it will eventually be vindicated.

    How then can intangible space be employed to construct tangible matter? The first clues are readily available in common life where we can observe many intangible objects but fail to note their true properties. For example, a knot in a string appears at first glance to be a tangible object. But when think more deeply, we can reason that the knot itself has neither surface nor substance, for these properties belong to the string. The crease in my pants is in a similar class. It is a one-dimensional discontinuity, a line a little under a yard long. A fold is something similar, as is a twist. When these intangible things are motionless, we talk of geometry and topology, but when they are in motion, then we then talk of action.

    To illustrate, consider a shout. Is a shout a thing? Can we measure its width? Can we measure its length? Can we identify its precise location? The answer to these questions is no, because a shout is an action. We understand what it is, we do not expect to find shout particles, and whilst we might consider it to be a thing, we consider it to be an intangible thing that we can neither touch nor grasp. A kick is another action. It exhibits no mass, colour, surface, or particles, and whilst it might therefore appear to be intangible, a kick from a pony will challenge that view. An action is not in fact intangible, and I will demonstrate how an action can be employed to construct matter.

    A photon is an action. Unlike a shout, which is a longitudinal wave moving in air, a photon is a transverse wave in space. The photon is customarily shown as a wavelike variation of the electric field accompanied by an orthogonal variation in the magnetic field, both being aspects of the electromagnetic field....
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  13. #12  
    Forum Professor sunshinewarrior's Avatar
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    Quote Originally Posted by Farsight
    Quote Originally Posted by Steve Miller
    Hello Farsight!

    I don't understand your last sentence. The end of the sentence the least.

    Or in other words again: what's different about the neutrino and the antineutrino is the direction of the action turn compared to the direction of propagation.
    Does that mean the whip running backwards from the actual crack to the moment the crack was set off?
    Not backwards in time. Just backwards. It's going the other way. If you've got a running loop that's turning in a clockwise direction. It can go this way O→ or this way ←O . There's nothing special about the clockwise direction. You could walk round to the other side of it and say it was turning in an anticlockwise direction. What's important is the direction of the turning action compared to the direction of propagation. One configuration is the mirror image of the other.

    The electron and positron are related in a similar fashion. Some people talk about a positron as a "time reversed electron", but it isn't. It's a mirror image of the electron. It's like your left and right hand, they have opposite "handedness" or chirality. The neutrino and antineutrino are similar, but we don't call it chirality we call it helicity, and there's no twist to keep them in place so they have no charge and they move more like a photon. You could say the photon is a transverse wave, the electron is a standing wave or soliton and the neutrino is a rolling wave, but I'm not sure that quite captures it. And I'm a bit cautious about using the word spin, because it tends to imply a "billiard ball particle" whirling like a dervish with topspin or backspin. It isn't like that. It's just action.

    A lot of people don't really know what action is. But it's quite easy when it clicks. Here's an excerpt from my paper A Qualitative 3+1 Dimensional Geometrical Model which is under review at a journal. It isn't accepted physics, but I'm confident that some significant elements of it will eventually be vindicated.

    How then can intangible space be employed to construct tangible matter? The first clues are readily available in common life where we can observe many intangible objects but fail to note their true properties. For example, a knot in a string appears at first glance to be a tangible object. But when think more deeply, we can reason that the knot itself has neither surface nor substance, for these properties belong to the string. The crease in my pants is in a similar class. It is a one-dimensional discontinuity, a line a little under a yard long. A fold is something similar, as is a twist. When these intangible things are motionless, we talk of geometry and topology, but when they are in motion, then we then talk of action.

    To illustrate, consider a shout. Is a shout a thing? Can we measure its width? Can we measure its length? Can we identify its precise location? The answer to these questions is no, because a shout is an action. We understand what it is, we do not expect to find shout particles, and whilst we might consider it to be a thing, we consider it to be an intangible thing that we can neither touch nor grasp. A kick is another action. It exhibits no mass, colour, surface, or particles, and whilst it might therefore appear to be intangible, a kick from a pony will challenge that view. An action is not in fact intangible, and I will demonstrate how an action can be employed to construct matter.

    A photon is an action. Unlike a shout, which is a longitudinal wave moving in air, a photon is a transverse wave in space. The photon is customarily shown as a wavelike variation of the electric field accompanied by an orthogonal variation in the magnetic field, both being aspects of the electromagnetic field....
    Fascinating. Thanks.

    shanks
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  14. #13  
    Forum Ph.D. Steve Miller's Avatar
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    Farsight,

    Do you kind of mashing this up? Do you refer to the loop or to particle(s ) (- physics ) properties?

    http://en.wikipedia.org/wiki/Helicit...cle_physics%29

    Steve
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  15. #14  
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    I thank you all for your answers.
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