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\centerline{\bf Special and General Relativity (PHZ 4601/5606) Fall 2017 
Solutions} \medskip

\centerline{\bf Set 4} 

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% \end{figure} \centerline{Potential as function of $z$.}

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\item{\bf 11. Rindler 2.9.}
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$$ \triangle x = \beta\,\triangle t = 8\,,$$
$$ (\triangle\tau)^2 = 64 = (\triangle t)^2\,(1-\beta^2) =
   \frac{64\,(1-\beta^2)}{\beta^2}\,, $$
$$ \beta^2 = 1 - \beta^2\ \Rightarrow\ \beta=\frac{1}{\sqrt{2}} =
   0.7071\dots \,.$$

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