# 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…

## 7 Citations

The Adventures of the Rocketeer: Accelerated Motion Under the Influence of Expanding Space*

- PhysicsPublications of the Astronomical Society of Australia
- 2010

Abstract It is well known that interstellar travel is bounded by the finite speed of light, but on very large scales any rocketeer would also need to consider the influence of cosmological expansion…

The kinematic component of the cosmological redshift

- Physics
- 2011

It is widely believed that the cosmological redshift is not a Doppler shift. However, Bunn & Hogg have recently pointed out that to solve this problem properly, one has to transport parallelly the…

There was movement that was stationary, for the four-velocity had passed around†

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Is the Doppler interpretation of galaxy redshifts in a Friedmann–Lemaitre–Robertson–Walker (FLRW) model valid in the context of the approach to comoving spatial sections pioneered by de Sitter,…

Using of the Generalized Special Relativity in Deriving the Equation of the Gravitational Red-Shift

- Physics
- 2011

In this work we present a study of a new method to prove the equation of the gravitational red shift of spec-tral lines. That’s according to the generalized special relativity theory. The equation of…

Bell’s Spaceships: The Views from Bow and Stern

- PhysicsPublications of the Astronomical Society of Australia
- 2018

Abstract Unravelling apparent paradoxes has proven to be a powerful tool for understanding the complexities of special relativity. In this paper, we focus upon one such paradox, namely Bell’s…

Can an infinitely long object fit in an expanding universe?

- PhysicsPublications of the Astronomical Society of Australia
- 2020

Abstract Does space stretch its contents as the universe expands? Usually, we say the answer is no—the stretching of space is not like the stretching of a rubber sheet that might drag things with it.…

Uniformly accelerated traveler in an FLRW universe

- PhysicsPhysical Review D
- 2020

This paper provides an analytical treatment of accelerated and geodesic motion within the framework of the Friedmann -Lemaitre-Robertson-Walker (FLRW) spacetime. By employing conformal time…

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