What's a 'real Neutral Particle'?

Most recent answer: 07/10/2013

Q:
I was doing some basic wikipedia research and I stumbled upon the concept of neutral particles. Here is the link: http://en.wikipedia.org/wiki/Neutral_particle So my question is what is the difference between a "neutral particle" that has no electrical charge vs. a "real neutral particle"? And why is a "real neutral particle" the same as as its antiparticle while a "neutral particle" isn't necessarily its own antiparticle, as implied by the wikipedia article? Thanks
- Aziz (age 22)
Glen Allen, VA, USA
A:

Hello Aziz,

I've been a card-carrying high energy physicist for over 25 years but I have never heard of the term  "real neutral particle" before.   I looked at the Wiki article you suggested and poked around a bit but couldn't find much enlightenment.  As far as I can tell it is what its definition says:  a particle with no electric charge and is it's own anti-particle.   There are examples such as photons, gravitons, Higg's bosons, etc.   Other neutral particles such as the neutron have distinct anti-particles, an anti-neutron in this case.  Neutrons are made out of quarks, anti-neutrons out of anti-quarks, they are different and have different quantum numbers.

 

LeeH


(published on 07/10/2013)