Antineutrino

[Rosemary]

I had a question about antimatter, and I wasn't sure where to ask it, so I thought I would try here.

 

I was wondering what the difference between antimatter and matter was.

 

Everything I have researched has said that it is charge, but that can not be true. Neutrinos are elementary particles, and they have antineutrinos, yet there charge is zero.

 

I saw several things about them being majorana particles, but each thing (at least the ones that know anything about neutrinos) says that they can not be majorana particles because they do not have vector interactions. I do not know what vector interactions have to do with them being majorana particles.

 

I have also heard of Strangeness being the other factor, but with neutrinos, there are not strange quarks, so you would have the same problem with that as you would have with charge.

 

Also, I recently heard that neatrinos were "right handed" and antineutrinos were "left handed", but in that case how would you know which was which?

 

Thanks,

Rosie

[ecoli]

from Wikipedia "Because antineutrinos and neutrinos are neutral particles it is possible that they are actually the same particle."

 

This means neutrinos would be a Majorana particle.

[BhavinB]

http://hyperphysics.phy-astr.gsu.edu/hbase/particles/neutrino3.html#c1

[ecoli]

http://hyperphysics.phy-astr.gsu.edu/hbase/particles/neutrino3.html#c1

 

opposite spin states, of course. But is that enough to be considered an anti-particle. I thought it had to be an opposite charge to be considered anti-matter.

[BhavinB]

'opposite' implies a linear negation. However, a true definition of antimatter is far more complicated. I'm not an expert to say what that means however. But to say all neutral particles are their own anti-particle is an incorrect statement.

 

ex: Neutron and anti-neutron

[swansont]

'opposite' implies a linear negation. However' date=' a true definition of antimatter is far more complicated. I'm not an expert to say what that means however. But to say all neutral particles are their own anti-particle is an incorrect statement.

 

ex: Neutron and anti-neutron[/quote']

 

But a neutron is not a fundamental particle - it's made up constituent particles (quarks) that have their own antiparticles, and are charged.

[BhavinB]

But a neutron is not a fundamental particle - it's made up constituent particles (quarks) that have their own antiparticles, and are charged.

 

Are you asserting also that a neutrino is its own anti-particle?

 

B

[swansont]

Are you asserting also that a neutrino is its own anti-particle?

 

B

 

 

No. I'm just saying that comparing the neutrino to the neutron isn't quite apples-to-apples. The only particles that are their own antiparticles, with which I am familiar, are Bosons. But I'm not a particle physicist.

[BhavinB]

No. I'm just saying that comparing the neutrino to the neutron isn't quite apples-to-apples. The only particles that are their own antiparticles, with which I am familiar, are Bosons. But I'm not a particle physicist.

 

me neither

 

What branch of physics do you study?

[swansont]

me neither

 

What branch of physics do you study?

 

Atomic. Specifically laser cooling and trapping, currently with regard to the application of the techniques to atomic clocks.

[Rosemary]

I would have thought they would be majorana particles, but I have read in several places, that they can not be majorana particles because they lack vector interactions (instead they have elastic interactions)