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\begin{document}

\title{No Faster-Than-Light Observers (GenRel)}
\author{%
	Mike Stannett\footnote{Corresponding author: \texttt{m.stannett@sheffield.ac.uk}}~, Edward Higgins\\
	\small{University of Sheffield, UK}
	\\[6pt]
	Hajnal Andr\'eka, Judit Madar\'asz, Istv\'an N\'emeti, Gergely Sz\'ekely$^{\dag}$\\
	\small{Alfr\'ed R\'enyi Institute of Mathematics, Budapest, Hungary}\\
	\small{($^{\dag}$ Secondary affiliation: University of Public Service, Budapest, Hungary)}}
\maketitle

\abstract{We have previously verified, in the first order theory \textsf{SpecRel} of Special Relativity, that inertial observers cannot travel faster than light \cite{NoFTLSR,No_FTL_observers-AFP}. We now prove the corresponding result for \textsf{GenRel}, the first-order theory of General Relativity. Specifically, we prove that whenever an observer $m$ encounters another observer $k$ (so that $m$ and $k$ are both present at some spacetime location $x$), $k$ will necessarily be observed by $m$ to be traveling at less than light speed.
}

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\end{document}

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