Measuring the Curvature of the Universe

TL;DR

This paper presents a method to measure the universe's curvature using features of the CMB spectrum, focusing on acoustic peak spacing and damping tail to provide robust, model-independent tests.

Contribution

It introduces a technique that relies on the gross features of the CMB spectrum, avoiding uncertainties in structure formation models.

Findings

Acoustic peak spacing and damping tail are effective for curvature measurement.

The method provides consistency tests to exclude exotic universe models.

Position of the first peak is less robust for curvature determination.

Abstract

We discuss how the curvature of the universe can be robustly measured employing only the gross features of the CMB anisotropy spectrum. Though the position of the first peak is not robust, uncertainties in the model for structure formation can be removed by using the spacing of the acoustic peaks and the location of the damping tail. Combined these provide important consistency tests that can be used to discriminate against a truly exotic model.