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arXiv · 1605.06426

Lifting Primordial Non-Gaussianity Above the Noise

Yvette Welling·Drian van der Woude·Enrico Pajer
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Abstract

Primordial non-Gaussianity (PNG) in Large Scale Structures is obfuscated by the many additional sources of non-linearity. Within the Effective Field Theory approach to Standard Perturbation Theory, we show that matter non-linearities in the bispectrum can be modeled sufficiently well to strengthen current bounds with near future surveys, such as Euclid. We find that the EFT corrections are crucial to this improvement in sensitivity. Yet, our understanding of non-linearities is still insufficient to reach important theoretical benchmarks for equilateral PNG, while, for local PNG, our forecast is more optimistic. We consistently account for the theoretical error intrinsic to the perturbative approach and discuss the details of its implementation in Fisher forecasts.

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Yvette Welling, Drian van der Woude, Enrico Pajer. 2016-05-20. Lifting Primordial Non-Gaussianity Above the Noise. https://doi.org/10.1088/1475-7516%2F2016%2F08%2F044

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