Cosmological radar ranging in an expanding universe

@article{Lewis2008CosmologicalRR,
  title={Cosmological radar ranging in an expanding universe},
  author={Geraint F. Lewis and Matthew Joseph Francis and Luke A. Barnes and Juliana Kwan and J. Berian James},
  journal={Monthly Notices of the Royal Astronomical Society},
  year={2008},
  volume={388},
  pages={960-964}
}
While modern cosmology, founded in the language of general relativity, is almost a century old, the meaning of the expansion of space is still being debated. In this paper, the question of radar ranging in an expanding universe is examined, focusing upon light travel times during the ranging; it has recently been claimed that this proves that space physically expands. We generalize the problem into considering the return journey of an accelerating rocketeer, showing that while this agrees with… 

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