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Updated: May 18, 2026

The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry

The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry

Published on: August 12, 2013

New window on primordial non-gaussianity.

Enrico Pajer¹, Matias Zaldarriaga

¹Department of Physics, Princeton University, Princeton, New Jersey 08544, USA.

Physical Review Letters

|October 4, 2012

Summary

Measurements of the cosmic microwave background

Area of Science:

Cosmology
Astrophysics
Cosmic Microwave Background

Background:

Primordial curvature perturbations on scales smaller than 1 Mpc are poorly understood.
The cosmic microwave background (CMB) spectrum offers a unique window into these scales.

Purpose of the Study:

To explore the unexplored range of scales (50 to 10^4 Mpc^-1) using CMB spectral distortions.
To utilize correlations between μ distortion and temperature anisotropies for testing primordial non-Gaussianity.

Main Methods:

Analysis of the μ distortion of the CMB spectrum.
Focus on low multipoles (l~100) of the μ distortion.
Fisher matrix forecast for observational constraints.

Main Results:

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Last Updated: May 18, 2026

The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry

The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry

Published on: August 12, 2013

Measurement of Scattering Nonlinearities from a Single Plasmonic Nanoparticle

Measurement of Scattering Nonlinearities from a Single Plasmonic Nanoparticle

Published on: January 3, 2016

Investigation of Early Plasma Evolution Induced by Ultrashort Laser Pulses

Investigation of Early Plasma Evolution Induced by Ultrashort Laser Pulses

Published on: July 2, 2012

Correlations between μ distortion and temperature anisotropies can probe primordial non-Gaussianity.
The μT two-point correlation measures f(NL)(loc) (primordial bispectrum), while μμ measures τ(NL) (primordial trispectrum).
A cosmic variance limited experiment could achieve Δf(NL)(loc) ~ O(10^-3).

Conclusions:

CMB spectral distortions provide a clean probe of small-scale primordial perturbations.
This method offers a unique opportunity to test Gaussianity at very small scales.
Future experiments can yield highly precise constraints on non-Gaussianity parameters.