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arXiv · 2109.01760

$Λ$CDM: Much more than we expected, but now less than what we want

Michael S. Turner
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Abstract

The $\rmΛ$CDM cosmological model is remarkable: with just 6 parameters it describes the evolution of the Universe from a very early time when all structures were quantum fluctuations on subatomic scales to the present, and it is consistent with a wealth of high-precision data, both laboratory measurements and astronomical observations. However, the foundation of $\rmΛ$CDM involves physics beyond the standard model of particle physics: particle dark matter, dark energy and cosmic inflation. Until this `new physics' is clarified, $\rmΛ$CDM is at best incomplete and at worst a phenomenological construct that accommodates the data. I discuss the path forward, which involves both discovery and disruption, some grand challenges and finally the limits of scientific cosmology.

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Michael S. Turner. 2021-09-04. $Λ$CDM: Much more than we expected, but now less than what we want. https://arxiv.org/abs/2109.01760

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