The Naked Scientists

The Naked Scientists Forum

Author Topic: What are neutrinos and what do they do?  (Read 9471 times)

Offline anerratic

  • First timers
  • *
  • Posts: 3
    • View Profile
What are neutrinos and what do they do?
« on: 24/08/2009 00:40:50 »
Hi everyone,

I was wondering what nuclear reactions neutrinos take part in and why. I know their properties, and a few of their sources, but i do not understand their role in some reactions such as beta decay. why are they needed?

Thanks,

anerratic.

[MOD EDIT - PLEASE PHRASE THREAD TITLES AS QUESTIONS, IN LINE WITH FORUM POLICY]
« Last Edit: 25/08/2009 10:18:52 by chris »


 

Offline Nizzle

  • Hero Member
  • *****
  • Posts: 964
  • Thanked: 1 times
  • Extropian by choice!
    • View Profile
    • Carnivorous Plants
Re: What are neutrinos and what do they do?
« Reply #1 on: 24/08/2009 10:48:11 »
They are needed to preserve conservation of energy, conservation of momentum, and conservation of angular momentum in beta decay
 

Offline syhprum

  • Neilep Level Member
  • ******
  • Posts: 3818
  • Thanked: 19 times
    • View Profile
Re: What are neutrinos and what do they do?
« Reply #2 on: 25/08/2009 06:44:25 »
Just a communication test!
 

Offline Nizzle

  • Hero Member
  • *****
  • Posts: 964
  • Thanked: 1 times
  • Extropian by choice!
    • View Profile
    • Carnivorous Plants
Re: What are neutrinos and what do they do?
« Reply #3 on: 25/08/2009 07:16:26 »
it worked,

i can read your post ::)
 

Offline Vern

  • Neilep Level Member
  • ******
  • Posts: 2072
    • View Profile
    • Photonics
What are neutrinos and what do they do?
« Reply #4 on: 25/08/2009 16:12:21 »
There is an interesting thing about the neutrino. It is the only particle suspected to exist that can not be annihilated to become photons. All other particles can be theoretically constructed by trapping photons in localized patterns.

Edit: I could change that to say if the neutrino is real, it is the only physical reality that can not be so reduced. So the neutrino nullifies a widely held belief of the early 20th century. I still suspect that old belief may in fact be the reality. It is "The final irreducible constituent of all physical reality is the electromagnetic field."
« Last Edit: 25/08/2009 16:22:58 by Vern »
 

Offline Lars Larsen

  • Jr. Member
  • **
  • Posts: 15
    • View Profile
What are neutrinos and what do they do?
« Reply #5 on: 26/08/2009 22:23:58 »
So the neutrino nullifies a widely held belief of the early 20th century. I still suspect that old belief may in fact be the reality. It is "The final irreducible constituent of all physical reality is the electromagnetic field."

What about gravitation?
 

Offline Vern

  • Neilep Level Member
  • ******
  • Posts: 2072
    • View Profile
    • Photonics
What are neutrinos and what do they do?
« Reply #6 on: 27/08/2009 12:00:24 »
Gravitation is no problem for a speculative soul. It is photon attraction for other photons. Everyone knows photons attract each other gravitationally.  However, most folks then seak some other source for gravitation in general. There is no need for some other source. If the final irreducible constituent of all physical reality is the electromagnetic field, photon-photon attraction would account for gravity.

The exact mechanism for photon-photon attraction is not known. But I suspect it is that photons exist as saturated points within fields of electric and magnetic force. The fields contribute toward the saturation amplitude, so photons must then migrate toward increasing amplitude of the fields.
 

Offline Lars Larsen

  • Jr. Member
  • **
  • Posts: 15
    • View Profile
What are neutrinos and what do they do?
« Reply #7 on: 27/08/2009 15:51:30 »
Gravitation is no problem for a speculative soul. It is photon attraction for other photons. Everyone knows photons attract each other gravitationally.  However, most folks then seak some other source for gravitation in general. There is no need for some other source. If the final irreducible constituent of all physical reality is the electromagnetic field, photon-photon attraction would account for gravity.

The exact mechanism for photon-photon attraction is not known. But I suspect it is that photons exist as saturated points within fields of electric and magnetic force. The fields contribute toward the saturation amplitude, so photons must then migrate toward increasing amplitude of the fields.

Jesus Christ, that blows my mind. That's exactly what Einstein and all the other guys were looking for all the time! GUT, TOE and so on. Put some math to it, dude, and the Nobel prize goes to... ;)
 

Offline Vern

  • Neilep Level Member
  • ******
  • Posts: 2072
    • View Profile
    • Photonics
What are neutrinos and what do they do?
« Reply #8 on: 27/08/2009 17:12:32 »
It's not much more than a hunch, but I suspect that there is a way to get to a GUT and TOE by considering everything in terms of the electromagnetic field. I compiled a list of evidence in support of that idea, but there is not enough interest among physicists for the idea to catch on.
 

lyner

  • Guest
What are neutrinos and what do they do?
« Reply #9 on: 27/08/2009 20:20:57 »
Vern
I took a look at your list in that link.
NO.17 caught my eye.
How do you relate the De Broglie wavelength displayed by a moving electron, when it is diffracted to an electromagnetic wavelength and a frequency of the photon you are postulating?
 

Offline DoctorBeaver

  • Naked Science Forum GOD!
  • *******
  • Posts: 12656
  • Thanked: 3 times
  • A stitch in time would have confused Einstein.
    • View Profile
What are neutrinos and what do they do?
« Reply #10 on: 28/08/2009 11:59:16 »
Gravitation is no problem for a speculative soul. It is photon attraction for other photons. Everyone knows photons attract each other gravitationally.  However, most folks then seak some other source for gravitation in general. There is no need for some other source. If the final irreducible constituent of all physical reality is the electromagnetic field, photon-photon attraction would account for gravity.

The exact mechanism for photon-photon attraction is not known. But I suspect it is that photons exist as saturated points within fields of electric and magnetic force. The fields contribute toward the saturation amplitude, so photons must then migrate toward increasing amplitude of the fields.

*brain explodes

Can you explain what you mean by saturated points? Are they points where the effect of the field is "stronger" (I may have used the wrong word there)? If the EM force is mitigated by photons and you say that photons are saturated points in the EM field, isn't that going round in circles?

I get very confused by fields so I'm probably trying to think in totally the wrong direction.

 

Offline Vern

  • Neilep Level Member
  • ******
  • Posts: 2072
    • View Profile
    • Photonics
What are neutrinos and what do they do?
« Reply #11 on: 28/08/2009 12:12:48 »
Quote from: sophiecentaur
How do you relate the De Broglie wavelength displayed by a moving electron, when it is diffracted to an electromagnetic wavelength and a frequency of the photon you are postulating?
I don't know how the De Broglie wavelength would compare to the calculated wavelength of an electron's photon. The calculated wavelength would be that of a photon with energy equivalent to an electron's mass. There would be lots of dynamics going on.
 

Offline Vern

  • Neilep Level Member
  • ******
  • Posts: 2072
    • View Profile
    • Photonics
What are neutrinos and what do they do?
« Reply #12 on: 28/08/2009 12:21:07 »
Quote from: DoctorBeaver
Can you explain what you mean by saturated points? Are they points where the effect of the field is "stronger" (I may have used the wrong word there)? If the EM force is mitigated by photons and you say that photons are saturated points in the EM field, isn't that going round in circles?
Consider the photon as consisting only of electromagnetic fields. Those planes radiating out from the photon's path are the fields. There are two points of maxima of the fields. These two points are at the centres of each half cycle of the photon wave. The points consist of the same stuff as the fields, but at a saturated amplitude. That saturated amplitude is the same in every photon. It is the maximum amplitude that space can support.

The point was that you can't make one of these from a neutrino. Every physical reality other than the neutrino can be reduced to photons.


« Last Edit: 28/08/2009 12:36:00 by Vern »
 

lyner

  • Guest
What are neutrinos and what do they do?
« Reply #13 on: 28/08/2009 13:33:12 »
Quote from: sophiecentaur
How do you relate the De Broglie wavelength displayed by a moving electron, when it is diffracted to an electromagnetic wavelength and a frequency of the photon you are postulating?
I don't know how the De Broglie wavelength would compare to the calculated wavelength of an electron's photon. The calculated wavelength would be that of a photon with energy equivalent to an electron's mass. There would be lots of dynamics going on.
The De Broglie  wavelength, which is what relates to electron diffraction, is a function of the momentum of the electron - not the mass. I think this may be a problem for you.

Also, your picture of a photon. You understand that a single cycle of a sine wave as you have drawn, involves an infinite number of  harmonics. How does that square with reality? You could expect, if that model of a photon applied, then photon interactions with charge systems and diffraction patterns might be expected to be very different. If you want to draw a picture of a photon I think you are trying to grab a wet bar of soap in a deep bath.
 

Offline Vern

  • Neilep Level Member
  • ******
  • Posts: 2072
    • View Profile
    • Photonics
What are neutrinos and what do they do?
« Reply #14 on: 28/08/2009 14:15:49 »
Quote from: sophiecentaur
The De Broglie  wavelength, which is what relates to electron diffraction, is a function of the momentum of the electron - not the mass. I think this may be a problem for you.
Yes; I know. That's one reason I never tried to compare this electron construct to De Broglie wavelength. I couldn't get my head around the dynamics enough to calculate a diffraction pattern.

And I know that an electromagnetic sine wave involves an infinite number of harmonics. It is just the nature of the beast, but I don't think that precludes an electromagnetic construct for mass. I know that it is very remote that I may have guessed the correct mechanisms for that construct of mass, but the numbers for the strong forces match up.

Calculator Source Code in C



 

Offline Nizzle

  • Hero Member
  • *****
  • Posts: 964
  • Thanked: 1 times
  • Extropian by choice!
    • View Profile
    • Carnivorous Plants
What are neutrinos and what do they do?
« Reply #15 on: 28/08/2009 14:41:02 »
Everyone knows photons attract each other gravitationally.

I feel left out here.. :(

How does a photon with 0 mass attract stuff? Especially heavier particles?
And if you're talking exclusively of photons attracting other photons, isn't it magnetic attraction rather than gravitational attraction?
 

Offline Vern

  • Neilep Level Member
  • ******
  • Posts: 2072
    • View Profile
    • Photonics
What are neutrinos and what do they do?
« Reply #16 on: 28/08/2009 14:47:40 »
No; photons attract each other gravitationally. I didn't just make that up.:) This is true in classical theory and in QM theory.

Edit: I don't remember exactly why, but I think this has to be so for some of the maths to work. I don't know of an experiment that would detect it.
« Last Edit: 28/08/2009 14:57:11 by Vern »
 

Offline Nizzle

  • Hero Member
  • *****
  • Posts: 964
  • Thanked: 1 times
  • Extropian by choice!
    • View Profile
    • Carnivorous Plants
What are neutrinos and what do they do?
« Reply #17 on: 28/08/2009 14:49:07 »
So mass is not a requirement for gravity?
 

Offline Farsight

  • Sr. Member
  • ****
  • Posts: 396
    • View Profile
What are neutrinos and what do they do?
« Reply #18 on: 28/08/2009 14:59:21 »
I think the dynamics is pretty simple Vern. Take a 511keV photon, wrap it in a double loop, and it traps itself. Check out John G Williamson's and Martin van der Mark's papers at http://www.cybsoc.org/cybcon2008prog.htm#jw. They're a little like you. They were formerly at CERN, they wrote a paper in 1991, and it took them siz six years to get it into a journal that few have heard of. That journal was Annales de la Fondation Louis de Broglie. See volume 22, no.2, 133 (1997). It's been "studiously ignored" ever since. John is doing a talk in London on the 12th September.



Nizzle: energy causes gravity. Mass causes gravity because of the energy content.
« Last Edit: 28/08/2009 15:51:44 by Farsight »
 

Offline Vern

  • Neilep Level Member
  • ******
  • Posts: 2072
    • View Profile
    • Photonics
What are neutrinos and what do they do?
« Reply #19 on: 28/08/2009 15:00:30 »
Quote
So mass is not a requirement for gravity?

Well, that depends on how you want to think of a photon. We say a photon has no mass. But we know that photons attract gravitationally. So in that sense, mass is not a requirement. But if you consider photons as a system, they are massive.

Edit: For example, photons trapped in a mirrored box add mass to the photon-box system.
« Last Edit: 28/08/2009 15:34:01 by Vern »
 

Offline Vern

  • Neilep Level Member
  • ******
  • Posts: 2072
    • View Profile
    • Photonics
What are neutrinos and what do they do?
« Reply #20 on: 28/08/2009 15:05:12 »
Quote
I think the dynamics is pretty simple Vern. Take a 511keV photon, wrap it in a double loop, and it traps itself. Check out John G Williamson's and Martin van der Mark's papers at http://www.cybsoc.org/cybcon2008prog.htm#jw.
Thanks Farsight; I'll check it out.
 

Offline Farsight

  • Sr. Member
  • ****
  • Posts: 396
    • View Profile
What are neutrinos and what do they do?
« Reply #21 on: 28/08/2009 15:44:02 »
Looking at the original post, whilst the neutrino is considered to be a lepton, it's doesn't hang around, and it doesn't have much in the way of mass. Hence it's arguably more like a photon than an electron. It doesn't have a "role" per se in Beta decay. A neutron is unstable outside the nucleus, and will undergo Beta-minus decay in about fifteen minutes, turning into a proton, an electron, and an antineutrino. The antineutrino flies off. It doesn't have many properties. It conveys energy, and whilst it has no charge and the mass is debateable, it does have a helicity or spin. IMHO the best way to conceptualize it is as a rolling wave or running loop. Take a look at Vern's image above of a photon, and relate it to this wave in a bullwhip:

   

It isn't quite like that, because a wave in three dimensional space wherein energy = pressure x volume has to be more like a pressure-pulse, where the sinusoidal waveform is giving you the slope. But nevermind the detail there. The moot point is that the neutrino is more like this:



Crack the whip and the running loop travels up its length. If the loop was running the other way, it would be an antineutrino. See http://hyperphysics.phy-astr.gsu.edu/HBASE/Particles/neutrino3.html for a little more on this.

Note that the photon "has no mass" because it's travelling at c. Trap it inside a mirrored box and the system that is the box+photon is now more massive. Here the photon is still moving at c, but not in aggregate with respect to you. If a neutrino travels at c, it has no mass, because mass is a measure of the amount of energy that is not moving at c with respect to you. Hence if the neutrino travels at less than c, it has some mass. If for some reason its speed varies, its mass will vary too. If this does happen, the loop will have to tighten or become multiple loops, which gives quite a nice picture of neutrino oscillation.   
« Last Edit: 28/08/2009 15:47:11 by Farsight »
 

Offline Vern

  • Neilep Level Member
  • ******
  • Posts: 2072
    • View Profile
    • Photonics
What are neutrinos and what do they do?
« Reply #22 on: 29/08/2009 00:59:43 »
Are you thinking that the speed of the neutrino may vary and that may cause it to oscillate through types of neutrinos?
 

Offline Farsight

  • Sr. Member
  • ****
  • Posts: 396
    • View Profile
What are neutrinos and what do they do?
« Reply #23 on: 29/08/2009 14:20:30 »
Yep.

Of course, it can seem a little more complicated, see http://en.wikipedia.org/wiki/Neutrino_oscillation. But the key thing that they don't understand is the relative-motion symmetry between momentum and inertia. A photon "has no mass", but stop it moving at c by trapping it in a mirrored box, or use pair production to make it go round and round as an electron, and the energy/momentum is now exhibited as mass. Mass is just a measure of how much energy is not moving in aggregate with respect to you. Search The Trouble with Physics for "motionless" and take a look at the first paragraph on page 105: http://www.amazon.co.uk/gp/reader/0141018356/ref=sib_vae_pg_105?ie=UTF8&keywords=motionless&p=S03N&twc=1&checkSum=cooQ%2Fqrry7NOMqep1awyTB6xeoXmJb4XYbCGZt8qv3o%3D#reader-page . Then look at the neutrino oscillation wiki article and note this:

"Eigenstates with different masses propagate at different speeds. The heavier ones lag behind while the lighter ones pull ahead".

That's back to front. If you've got something going past you at c there's no mass. Make it travel at an aggregate of 0 km/s and it's all mass. And it's a sliding scale in between. Something concertinaing along will have a variable mass because the velocity varies. When it slows down the mass increases. When it speeds up the mass decreases. All simple stuff once it clicks.   
 

Offline Vern

  • Neilep Level Member
  • ******
  • Posts: 2072
    • View Profile
    • Photonics
What are neutrinos and what do they do?
« Reply #24 on: 29/08/2009 17:24:36 »
Quote from: Farsight
When it slows down the mass increases. When it speeds up the mass decreases. All simple stuff once it clicks.
It is difficult for this to click for me. Momentum is velocity times mass. I suppose if you did the exchange just right momentum would still be conserved and give some validity to it.
 

The Naked Scientists Forum

What are neutrinos and what do they do?
« Reply #24 on: 29/08/2009 17:24:36 »

 

SMF 2.0.10 | SMF © 2015, Simple Machines
SMFAds for Free Forums