A Space & astronomy forum. SpaceBanter.com

Go Back   Home » SpaceBanter.com forum » Astronomy and Astrophysics » Astronomy Misc
Site Map Home Authors List Search Today's Posts Mark Forums Read Web Partners

Do I understand this correctly?



 
 
Thread Tools Display Modes
  #1  
Old November 24th 10, 03:25 PM posted to sci.physics,sci.astro
Joe Snodgrass
external usenet poster
 
Posts: 15
Default Do I understand this correctly?


Am I correct in my understanding that, although it was discovered in
1998 that the neutrino does indeed have mass, people still don't know
what that mass is? TIA.
  #2  
Old November 24th 10, 03:56 PM posted to sci.physics,sci.astro
Sam Wormley[_2_]
external usenet poster
 
Posts: 3,966
Default Do I understand this correctly?

On 11/24/10 8:25 AM, Joe Snodgrass wrote:

Am I correct in my understanding that, although it was discovered in
1998 that the neutrino does indeed have mass, people still don't know
what that mass is? TIA.


Background
http://en.wikipedia.org/wiki/Neutrino

Generation 1
Electron neutrino νe 2.2 eV
Electron antineutrino νe 2.2 eV
Generation 2
Muon neutrino νμ 170 keV
Muon antineutrino νμ 170 keV
Generation 3
Tau neutrino ντ 15.5 MeV
Tau antineutrino ντ 15.5 MeV


  #3  
Old November 24th 10, 04:26 PM posted to sci.physics,sci.astro
Martin Brown
external usenet poster
 
Posts: 1,707
Default Do I understand this correctly?

On 24/11/2010 14:56, Sam Wormley wrote:
On 11/24/10 8:25 AM, Joe Snodgrass wrote:

Am I correct in my understanding that, although it was discovered in
1998 that the neutrino does indeed have mass, people still don't know
what that mass is? TIA.


Background
http://en.wikipedia.org/wiki/Neutrino

Generation 1
Electron neutrino νe 2.2 eV
Electron antineutrino νe 2.2 eV
Generation 2
Muon neutrino νμ 170 keV
Muon antineutrino νμ 170 keV
Generation 3
Tau neutrino ντ 15.5 MeV
Tau antineutrino ντ 15.5 MeV



I have to say I find it hard to reconcile the table of numbers given
above with the paper summarised in Science that put a rough bound on the
sum of the (rest) masses of the three types of neutrino at 0.28eV.

http://www.sciencedaily.com/releases...0712115104.htm

Regards,
Martin Brown
  #4  
Old November 24th 10, 06:01 PM posted to sci.astro,sci.physics
John Park
external usenet poster
 
Posts: 155
Default Do I understand this correctly?

Martin Brown ) writes:
On 24/11/2010 14:56, Sam Wormley wrote:
On 11/24/10 8:25 AM, Joe Snodgrass wrote:

Am I correct in my understanding that, although it was discovered in
1998 that the neutrino does indeed have mass, people still don't know
what that mass is? TIA.


Background
http://en.wikipedia.org/wiki/Neutrino

Generation 1
Electron neutrino νe 2.2 eV
Electron antineutrino νe 2.2 eV
Generation 2
Muon neutrino νμ 170 keV
Muon antineutrino νμ 170 keV
Generation 3
Tau neutrino ντ 15.5 MeV
Tau antineutrino ντ 15.5 MeV



I have to say I find it hard to reconcile the table of numbers given
above with the paper summarised in Science that put a rough bound on the
sum of the (rest) masses of the three types of neutrino at 0.28eV.

http://www.sciencedaily.com/releases...0712115104.htm

Well there's no actual inconsistency, since the numbers quoted were all upper
bounds. I think it's harder to put a limit on the mass of one species in
isolation than to estimate the total mass of all species (particle
physics vs astrophysics?).

--John Park
  #5  
Old November 24th 10, 07:20 PM posted to sci.astro
߃-- ¹¹
external usenet poster
 
Posts: 38
Default Do I understand this correctly?

The neutrino was "invented" to keep false theory from falling apart.
Another phantom particle, made to fit establishment particle physics,
that has impossible qualities, and really doesn't exist in our reality,
but keeps Big Bang lovers happy.

߃--¹¹

  #6  
Old November 24th 10, 07:40 PM posted to sci.physics,sci.astro
PD
external usenet poster
 
Posts: 1,572
Default Do I understand this correctly?

On Nov 24, 8:25*am, Joe Snodgrass wrote:
Am I correct in my understanding that, although it was discovered in
1998 that the neutrino does indeed have mass, people still don't know
what that mass is? *TIA.


What we know is that neutrinos oscillate between "flavors" -- muon
neutrinos to electron neutrinos and vice versa, tau neutrinos to muon
neutrinos and vice versa, etc. We have seen such behavior in hadrons,
including K mesons containing strange quarks, and mesons containing
charm and bottom quarks. You can google "K-long K-short" if you like.

Quantum mechanically, the oscillation is expected from a mixture of
states being produced, and the oscillation rate is proportional to the
difference between the squares of the neutrino masses, and so this is
the quantity that's been measured. If all the neutrinos were massless,
then the difference would be zero, and the oscillation rate would be
zero. This, however, doesn't tell you what the masses are, only that
they are different.

Technically, the situation is a bit more muddled, because the neutrino
*mass* states are not identical to neutrino *flavor* states. One is a
mixture of the other. Thus, if you form a specific *mass* state, then
you are producing a mix of flavor states, and an oscillation will
occur between mass states; and vice versa.

PD
  #7  
Old November 24th 10, 07:53 PM posted to sci.physics,sci.astro
hanson
external usenet poster
 
Posts: 2,934
Default Do I understand this correctly?

Joe Snodgrass wrote:
Am I correct in my understanding that, although it was discovered in
1998 that the neutrino does indeed have mass, people still don't
know what that mass is? TIA.

Paul "PD" wrote:
What we know is that neutrinos oscillate between "flavors" -- muon
neutrinos to electron neutrinos and vice versa, tau neutrinos to muon
neutrinos and vice versa, etc. We have seen such behavior in hadrons,
including K mesons containing strange quarks, and mesons containing
charm and bottom quarks. You can google "K-long K-short" if you like.

Quantum mechanically, the oscillation is expected from a mixture of
states being produced, and the oscillation rate is proportional to the
difference between the squares of the neutrino masses, and so this is
the quantity that's been measured. If all the neutrinos were massless,
then the difference would be zero, and the oscillation rate would be
zero. This, however, doesn't tell you what the masses are, only that
they are different.

Technically, the situation is a bit more muddled, because the neutrino
*mass* states are not identical to neutrino *flavor* states. One is a
mixture of the other. Thus, if you form a specific *mass* state, then
you are producing a mix of flavor states, and an oscillation will
occur between mass states; and vice versa.

hanson wrote:
.... ahahaha...Paul, you write "This, however, doesn't tell you
what the masses are, only that they are different."... ahahaha..
and then you go and write a lengthy tripe around it, instead
of explaining what "mass" FUNDAMENTALLY means. Bad
pedagogic, Paul...Now, explain to Joe what "mass" here is.
TFTLIA... ahahahaha... ahahahahanson


  #8  
Old November 24th 10, 08:13 PM posted to sci.physics,sci.astro
PD
external usenet poster
 
Posts: 1,572
Default Do I understand this correctly?

On Nov 24, 12:53*pm, "hanson" wrote:
Joe Snodgrass wrote:

Am I correct in my understanding that, although it was discovered in
1998 that the neutrino does indeed have mass, people still don't
know what that mass is? TIA.

Paul "PD" wrote:

*What we know is that neutrinos oscillate between "flavors" -- muon
neutrinos to electron neutrinos and vice versa, tau neutrinos to muon
neutrinos and vice versa, etc. We have seen such behavior in hadrons,
including K mesons containing strange quarks, and mesons containing
charm and bottom quarks. You can google "K-long K-short" if you like.

Quantum mechanically, the oscillation is expected from a mixture of
states being produced, and the oscillation rate is proportional to the
difference between the squares of the neutrino masses, and so this is
the quantity that's been measured. If all the neutrinos were massless,
then the difference would be zero, and the oscillation rate would be
zero. This, however, doesn't tell you what the masses are, only that
they are different.

Technically, the situation is a bit more muddled, because the neutrino
*mass* states are not identical to neutrino *flavor* states. One is a
mixture of the other. Thus, if you form a specific *mass* state, then
you are producing a mix of flavor states, and an oscillation will
occur between mass states; and vice versa.

hanson wrote:

... ahahaha...Paul, you write "This, however, doesn't tell you
what the masses are, only that they are different."... ahahaha..
and then you go and write a lengthy tripe around it, instead
of explaining what "mass" FUNDAMENTALLY means. Bad
pedagogic, Paul...Now, explain to Joe what "mass" here is.
TFTLIA... ahahahaha... ahahahahanson


I don't think that was his question, hanson.
If you want to know what mass fundamentally means, why don't you make
a new post with that question?
  #9  
Old November 24th 10, 08:20 PM posted to sci.physics,sci.astro
Androcles[_35_]
external usenet poster
 
Posts: 14
Default Do I understand this correctly?


"PD" wrote in message
...
On Nov 24, 12:53 pm, "hanson" wrote:
Joe Snodgrass wrote:

Am I correct in my understanding that, although it was discovered in
1998 that the neutrino does indeed have mass, people still don't
know what that mass is? TIA.

Paul "PD" wrote:

What we know is that neutrinos oscillate between "flavors" -- muon
neutrinos to electron neutrinos and vice versa, tau neutrinos to muon
neutrinos and vice versa, etc. We have seen such behavior in hadrons,
including K mesons containing strange quarks, and mesons containing
charm and bottom quarks. You can google "K-long K-short" if you like.

Quantum mechanically, the oscillation is expected from a mixture of
states being produced, and the oscillation rate is proportional to the
difference between the squares of the neutrino masses, and so this is
the quantity that's been measured. If all the neutrinos were massless,
then the difference would be zero, and the oscillation rate would be
zero. This, however, doesn't tell you what the masses are, only that
they are different.

Technically, the situation is a bit more muddled, because the neutrino
*mass* states are not identical to neutrino *flavor* states. One is a
mixture of the other. Thus, if you form a specific *mass* state, then
you are producing a mix of flavor states, and an oscillation will
occur between mass states; and vice versa.

hanson wrote:

... ahahaha...Paul, you write "This, however, doesn't tell you
what the masses are, only that they are different."... ahahaha..
and then you go and write a lengthy tripe around it, instead
of explaining what "mass" FUNDAMENTALLY means. Bad
pedagogic, Paul...Now, explain to Joe what "mass" here is.
TFTLIA... ahahahaha... ahahahahanson


I don't think
====================
We already know that, Duck. No need to repeat it.




  #10  
Old November 24th 10, 08:29 PM posted to sci.physics,sci.astro
Sam Wormley[_2_]
external usenet poster
 
Posts: 3,966
Default Do I understand this correctly?

On 11/24/10 8:25 AM, Joe Snodgrass wrote:

Am I correct in my understanding that, although it was discovered in
1998 that the neutrino does indeed have mass, people still don't know
what that mass is? TIA.


Using cold atoms to measure neutrino mass
http://george.ph.utexas.edu/papers/neutrino_mass.pdf

 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
everyone correctly witness outside Chester when the systematic youths present onto the alive rear [email protected] Amateur Astronomy 0 August 14th 07 10:19 AM
Let's see if I understand this correctly FB Astronomy Misc 1 March 20th 07 10:38 PM
Do we really understand the Sun? SuperCool Plasma Misc 0 May 25th 05 02:48 PM
Saturn's moons, now named correctly Chris Taylor UK Astronomy 10 November 16th 04 12:21 AM


All times are GMT +1. The time now is 12:32 PM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 SpaceBanter.com.
The comments are property of their posters.