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arXiv · 2310.11977

Constraints on dark energy from TDCOSMO & SLACS lenses

Natalie B. Hogg
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Abstract

Problems with the cosmological constant model of dark energy motivate the investigation of alternative scenarios. I make the first measurement of the dark energy equation of state using the hierarchical strong lensing time delay likelihood provided by TDCOSMO. I find that the combination of seven TDCOSMO lenses and 33 SLACS lenses is only able to provide a weak constraint on the dark energy equation of state, $w < -1.75$ at 68% confidence, which nevertheless implies the presence of a phantom dark energy component. When the strong lensing time delay data is combined with a collection of cosmic microwave background, baryon acoustic oscillation and Type Ia supernova data, I find that the equation of state is $w = -1.025\pm 0.029$.

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Natalie B. Hogg. 2023-10-18. Constraints on dark energy from TDCOSMO & SLACS lenses. https://doi.org/10.1093/mnrasl%2Fslae005

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