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arXiv · 2209.13029

A Forecast for Large Scale Structure Constraints on Horndeski Gravity with Line Intensity Mapping

Bryan R. Scott·Kirit S. Karkare·Simeon Bird
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Abstract

We consider the potential for line intensity mapping (LIM) of the rotational CO(1-0), CO(2-1) and CO(3-2) transitions to detect deviations from General Relativity from $0 < z < 3$ within the framework of a very general class of modified gravity models, called Horndeski theories. Our forecast assumes a multi-tracer analysis separately obtaining information from the matter power spectrum and the first two multipoles of the redshift space distortion power spectrum. To achieve $\pm 0.1$ level constraints on the slope of the kinetic gravity braiding and Planck mass evolution parameters, a mm-wave LIM experiment would need to accumulate $\approx 10^8-10^9$ spectrometer hours, feasible with instruments that could be deployed in the 2030s. Such a measurement would constrain large portions of the remaining parameter space available to Scalar-Tensor modified gravity theories. Our modeling code is publicly available.

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Bryan R. Scott, Kirit S. Karkare, Simeon Bird. 2022-09-26. A Forecast for Large Scale Structure Constraints on Horndeski Gravity with Line Intensity Mapping. https://doi.org/10.1093/mnras/stad1501

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