Calculating the Eta Particle's Composition

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Discussion Overview

The discussion centers around the composition of the eta particle, specifically the expression for its state in terms of quark-antiquark pairs. Participants explore the theoretical framework underlying this representation, including aspects of SU(3) flavor symmetry.

Discussion Character

  • Technical explanation, Conceptual clarification

Main Points Raised

  • One participant questions the expression for the eta particle, seeking clarification on its formulation.
  • Another participant explains that the eta particle's expression represents a definite-weight state of SU(3) flavor, referring to its eigenstate properties related to specific SU(3) generators.
  • A later reply draws an analogy between the eta particle's state and the product states of two spin 1/2 particles, noting the complexity introduced by the additional generators in SU(3) compared to SU(2).
  • One participant requests a reference for further reading on the topic.
  • A reference to Howard Georgi's "Lie Algebras In Particle Physics" is provided as a standard source for this subject matter.

Areas of Agreement / Disagreement

Participants do not express disagreement, but the discussion remains focused on clarifying the theoretical aspects of the eta particle's composition without reaching a consensus on additional interpretations or implications.

Contextual Notes

The discussion does not address potential limitations or assumptions underlying the SU(3) framework or the specific expression for the eta particle.

yola
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Why is the eta particle written as 1/sqrt(6) *(uu(bar) + dd(bar) -2ss(bar))?
Thanks
 
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Because that's a definite-weight state of SU(3) flavor. And by definite-weight state I mean an eigenstate of specific SU(3) generators (specifically what are called Casimir operators, the analog of \vec{J}^2 for SU(2)). It's analogous to working out the product states of two spin 1/2 particles, but a little bit more complicated because the algebra of SU(3) has more generators than SU(2).
 
Last edited:
Can you please specify for me a reference to check?
Thanks
 
Howard Georgi, "Lie Algebras In Particle Physics" is a standard reference.
 
Great, Thanks
 

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