Geoffrey Endean has published some interesting papers on Cosmology in Conformally Flat Spacetime [1], but Laurent Querella [2] claims that "the arguments leading to Endean's conclusions are incorrect, and we reject his CFS cosmology".(adsbygoogle = window.adsbygoogle || []).push({});

However, this section (3.1) of Querella's paper seems to be based on a non-standard (mis)interpretation of the identity [tex]d\tau_0 \equiv dt_0[/tex]. The standard meaning of this identity is that the rates of two clocks aredefinedto be the same in the current epoch, but Querella seems to have (wrongly) assumed that Endean was defining [tex]d\tau \equiv dt[/tex] so that the rates of these two clocks are defined to be the same in every epoch.

Do you think that this statement by Querella makes sense, or do you think that he has misinterpreted the meaning of [tex]d\tau_0 \equiv dt_0[/tex]? Querella section 3.1 said:Turning aside from the interpretation of equations (9) Endean (1997) states a new “principle of identical clock rates” asserting that the flows of CFS and cosmic times are identical, viz. [tex]d\tau_0 \equiv dt_0[/tex]. This, a major offense, shows unambiguously that CFS cosmology is fundamentally unsound. For instance, this “principle” has the awkward consequence that K is no longer constant but determined as a function of [tex]\eta[/tex], namely [tex]K(\eta) = 1/sin^2\eta[/tex]. This is in total contradiction with the exact solution (8).

[1] Geoffrey Endean, Cosmology in Conformally Flat Spacetime, The Astrophysical Journal, 479: 40-45, 1997 April 10.

[2] Laurent Querella, Kinematic Cosmology in Conformally Flat Spacetime, The Astrophysical Journal, 508:129-131, 1998 November 20, http://arxiv.org/abs/gr-qc/9807020.

.

**Physics Forums - The Fusion of Science and Community**

Dismiss Notice

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Cosmology in Conformally Flat Spacetime

Can you offer guidance or do you also need help?

Draft saved
Draft deleted

Loading...

Similar Threads - Cosmology Conformally Flat | Date |
---|---|

I Stress–energy pseudotensor of gravitation field for DE | Jan 30, 2018 |

I Metric for the Lambdavacuum | Aug 26, 2017 |

A Hawking and Unruh effects -- Differences and interpretation | Aug 1, 2017 |

I How to show that Electrodynamics is conformally invariant? | Jul 27, 2016 |

**Physics Forums - The Fusion of Science and Community**