What is the meaning behind the quark content of the neutral pion?

websterling
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The quark content of the neutral pion is listed as \frac{u\overline{u}-d\overline{d}}{\sqrt{2}} What is the proper way to interpret this?
 
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Can you elaborate? Is your question related to the quantum mechanical interpretation of a superposition of states, or is it more directly related to particle physics? If it is about particle physics, then perhaps the more appropriate way to look at this superposition is as a consequence of the approximate isospin symmetry.
 
what is \frac{u\overline{u}+d\overline{d}}{\sqrt{2}} ? :confused:
 
tiny-tim said:
what is \frac{u\overline{u}+d\overline{d}}{\sqrt{2}} ? :confused:

That should be a "-" instead of a "+" in the expession- it was correct in my original post.

In, for example, the Wikipedia Pion article, the positive pion's quark composition is listed as u\overline{d}, and the neutral pion's composition is listed as u\overline{u} or d\overline{d}

Additionally, the neutral pion's quark content is listed as\frac{u\overline{u}-d\overline{d}}{\sqrt{2}}

My question is, from a particle physics standpoint, how is \frac{u\overline{u}-d\overline{d}}{\sqrt{2}} related to u\overline{u} or d\overline{d}?
 
It represents a superposition of the two; the sqrt(2) is the normalization factor.
 
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