Fundamental Physics with the Lyman-Alpha Forest: Constraints on the Growth of Structure and Neutrino Masses from SDSS...

We present an effective field theory (EFT) approach to extract fundamental cosmological parameters from the Lyman-alpha forest flux fluctuations as an alternative to the standard simulation-based techniques. As a first application, we reanalyze the publicly available one-dimensional Lyman-alpha flux power spectrum data from the Sloan Digital Sky Survey. Our analysis relies on informative priors on EFT parameters that we extract from a combination of public hydrodynamic simulation and emulator data. Assuming the concordance cosmological model, our one-parameter analysis yields a 2% measurement of the late time mass fluctuation amplitude σ_{8}=0.841±0.017, or equivalently, the structure growth parameter S_{8}=0.852±0.017, consistent with the standard cosmology. This result is obtained assuming that nonlinear EFT parameters are cosmology-independent functions of the linear bias parameter. When this assumption is loosened, the limit degrades by a factor of 3, suggesting that informative priors are necessary for competitive constraints. Combining our EFT likelihood with Planck+baryon acoustic oscillation data, we find a new constraint on the total neutrino mass, ∑m_{ν}<0.08  eV (at 95% CL). Our study defines priorities for the development of EFT methods and sets the benchmark for cosmological analyses of the Lyman-alpha forest data from the Dark Energy Spectroscopic Instrument.