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arXiv · 1711.10369

Tests of $Λ$CDM and Conformal Gravity using GRB and Quasars as Standard Candles out to $z \sim 8$

Carl Roberts·Keith Horne·Alistair O. Hodson·Alasdair Dorkenoo Leggat
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Abstract

We compare the cosmology of conformal gravity (CG), (Mannheim 2006), to $Λ$CDM. CG cosmology has repulsive matter and radiation on cosmological scales, while retaining attractive gravity at local scales. Mannheim (2003) finds that CG agrees with $Λ$CDM for supernova data at redshifts $z<1$. We use GRBs and quasars as standard candles to contrast these models in the redshift range $0<z<8$. We find CG deviates significantly from $Λ$CDM at high redshift and that $Λ$CDM is favoured by the data with $Δχ^2=48$. Mannheim's model has a bounded dark energy contribution, but we identify a $λ$ fine-tuning problem and a cosmic coincidence problem.

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Carl Roberts, Keith Horne, Alistair O. Hodson, Alasdair Dorkenoo Leggat. 2017-11-28. Tests of $Λ$CDM and Conformal Gravity using GRB and Quasars as Standard Candles out to $z \sim 8$. https://arxiv.org/abs/1711.10369

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