Talk:Pseudorapidity

Untitled

The table should be extended to $\theta =180^{\circ }$

{Relation to rapidity in limit} The following statement: "...in the approximation that the mass of the particle is nearly zero, pseudorapidity is numerically close to the experimental particle physicist's definition of rapidity" is too vague. In this limit pseudorapidity _equals_ rapidity. Just plug in m=0 in the formula — Preceding unsigned comment added by 83.89.32.26 (talk) 19:17, 16 May 2012 (UTC)

{Correction} If one express

$\tan {\frac {\theta }{2}}={\frac {\sin {\frac {\theta }{2}}}{\cos {\frac {\theta }{2}}}}={\sqrt {\frac {1-\cos \theta }{1-\sin \theta }}}$

while the longitudinal and trasversal components of momentum $\mathbf {p}$ are

$p_{T}=|\mathbf {p} |\sin \theta$

and

$p_{L}=|\mathbf {p} |\cos \theta$

the result for $\eta$ is

$\eta ={\frac {1}{2}}\ln \left[{\frac {|\mathbf {p} |-p_{L}}{|\mathbf {p} |-p_{T}}}\right]$ — Preceding unsigned comment added by 200.1.26.102 (talk) 18:54, 29 April 2013 (UTC)

Hyperbolic geometry

This article is about an application of angle of parallelism, a key metric concept in hyperbolic geometry. The equations find the angle of parallelism based on a leg of an ideal triangle in the hyperbolic plane. Today the reference to Chiochia was added, but we need a reference that tells how the particle scientists came to exploit hyperbolic geometry this way. — Rgdboer (talk) 22:01, 6 October 2015 (UTC)