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Updated: Oct 2, 2025

The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry
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Why Must Primordial Non-Gaussianity Be Very Small?

Jason Kristiano1,2, Jun'ichi Yokoyama1,2,3,4

  • 1Research Center for the Early Universe (RESCEU), Graduate School of Science, The University of Tokyo, Tokyo 113-0033, Japan.

Physical Review Letters
|February 25, 2022
PubMed
Summary

One-loop corrections to the primordial power spectrum in single-field inflation are significantly larger than expected. This implies primordial non-Gaussianity must be smaller than current bounds to ensure cosmological perturbation theory remains valid.

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