Observing the evolution of the CMB

TL;DR

This paper investigates the potential to observe short-term changes in the Cosmic Microwave Background (CMB), finding that certain effects like the dipole shift could be detectable within a decade, while higher multipole changes require millennia.

Contribution

It quantifies the detectability of short-term CMB variations, highlighting the feasibility of observing galactic motion effects within a decade.

Findings

Dipole change detectable in ~10 years

Higher multipole changes detectable in ~4000 years

Future experiments could observe CMB evolution on short time scales

Abstract

Most cosmological parameters are expected to change significantly only on cosmological time scales, but given the large amount of information contained within the Cosmic Microwave Background (CMB) sky, we can expect that changes in the CMB should be observable on much shorter time scales. Here we quantify this expectation, examining the detectability of the dominant effects on short time scales. We find that an ideal future experiment with currently achievable sensitivity could detect the changing dipole due to our galactic motion in about 10 years, but that it would take around 4000 years to detect a change in the higher order multipoles.