4 ms·

Is this what I've heard called "particle zoo" research, where they're just using higher and higher energies to pile up more and more improbable bundles of funda

Is this what I've heard called "particle zoo" research, where they're just using higher and higher energies to pile up more and more improbable bundles of fundamental stuff?

maaku 12y ago
Yes. It's somewhat shameful that we physicists still call these constructs 'particles' as to the lay person this still implies some sort of fundamental nature. They are actually predicted constructs of still smaller particles that only appear momentarily at sufficiently high energy. That said, it is important, interesting research because if there are important deviations from the standard model, it is likely to be hinted at by the actual mass values among other things.
- cbd1984 12y ago
  > It's somewhat shameful that we physicists still call these constructs 'particles' Are they any less particle-like than an electron? Than a proton? Even though a proton isn't fundamental, it's still considered a particle.
  - cozzyd 12y ago
    Well, there is clearly a hierarchy of importance of particles, although I don't know a very clear cut criterion (other than being "interesting"). Protons and neutrons are clearly important, but excited states thereof (e.g. N(1440), N(1520), etc., see http://pdg8.lbl.gov/rpp2014v1/pdgLive/ParticleGroup.action?node=BXXX005 http://pdg8.lbl.gov/rpp2014v1/pdgLive/ParticleGroup.action?n...) are clearly less so. Their masses and quantum numbers obviously tell us something about how baryons work, but nobody will get too excited about N(XXXX).
  - duaneb 12y ago
    I would imagine the particulate properties would change at different scales, energies, etc, so being a 'particle' is an emergent property of more fundamental states.
  - maaku 12y ago
    Electrons are fundamental particles as far as we know, protons are not. You can shoot something at a proton and see that there are three little things inside. That is I think an important distinction to make.

Is this what I've heard called "particle zoo" research, where they're just using higher and higher energies to pile up more and more improbable bundles of fundamental stuff?

maaku 12y ago

Yes. It's somewhat shameful that we physicists still call these constructs 'particles' as to the lay person this still implies some sort of fundamental nature. They are actually predicted constructs of still smaller particles that only appear momentarily at sufficiently high energy. That said, it is important, interesting research because if there are important deviations from the standard model, it is likely to be hinted at by the actual mass values among other things.

cbd1984 12y ago
> It's somewhat shameful that we physicists still call these constructs 'particles' Are they any less particle-like than an electron? Than a proton? Even though a proton isn't fundamental, it's still considered a particle.
- cozzyd 12y ago
  Well, there is clearly a hierarchy of importance of particles, although I don't know a very clear cut criterion (other than being "interesting"). Protons and neutrons are clearly important, but excited states thereof (e.g. N(1440), N(1520), etc., see http://pdg8.lbl.gov/rpp2014v1/pdgLive/ParticleGroup.action?node=BXXX005 http://pdg8.lbl.gov/rpp2014v1/pdgLive/ParticleGroup.action?n...) are clearly less so. Their masses and quantum numbers obviously tell us something about how baryons work, but nobody will get too excited about N(XXXX).
- duaneb 12y ago
  I would imagine the particulate properties would change at different scales, energies, etc, so being a 'particle' is an emergent property of more fundamental states.
- maaku 12y ago
  Electrons are fundamental particles as far as we know, protons are not. You can shoot something at a proton and see that there are three little things inside. That is I think an important distinction to make.