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The dimensions in the equation

${\displaystyle \xi _{+1}({\vec {p}})={\sqrt {\frac {2|{\vec {p}}|}{|{\vec {p}}|+p_{z}}}}{\begin{pmatrix}|{\vec {p}}|+p_{z}\\p_{x}+ip_{y}\end{pmatrix}}={\begin{pmatrix}\cos {\frac {\theta }{2}}\\e^{i\phi }\sin {\frac {\theta }{2}}\end{pmatrix}}\,}$

are definitely wrong as cos and sin are dimensionless. — Preceding unsigned comment added by Hardi27 ( talk • contribs) 09:53, 30 September 2012 (UTC) reply

It appears to have been fixed at some point. 67.198.37.16 ( talk) 03:09, 1 December 2020 (UTC) reply

It is not clear from the article what ${\displaystyle \chi _{\lambda }}$ is. I assume it is supposed to be a helicity eigenstate, like ${\displaystyle \xi _{\lambda }}$, but it is not actually defined as such anywhere. ( Bjfar ( talk) 03:10, 22 April 2013 (UTC)) reply

I'm fairly confident that ${\displaystyle \chi _{\lambda }=\xi _{\lambda }}$ and its just a screw-up typo in the equations. But not my ball-o-wax, so I won't mess with it. Yes this needs to be fixed. 67.198.37.16 ( talk) 03:16, 1 December 2020 (UTC) reply