Cosmic Inflation and Structure Formation Through Global Analysis

Introduction

During the last decades, high-precision experiments have made increasingly detailed measurements of diffuse Extragalactic Background Light (EBL) emitted by cosmological sources. This has revolutionized the understanding of our cosmic origins.

Importance of Cosmic Measurements

The Cosmic Microwave Background (CMB) is our most precious resource for understanding the Big Bang, while the Cosmic Infrared and Optical Backgrounds (CIB and COB) provide unique constraints on the evolution of large-scale structure from the first galaxies to today.

Challenges in Measurement

Until recently, measurements of these effects were limited by either foregrounds or instrumental noise. However, the combined signal-to-noise ratio has now grown so large that the interplay between astrophysical confusion and instrumental systematic uncertainties dominates the error budget.

Objectives of the Origins Project

To make further progress, it has become critical to account for all sources of uncertainties simultaneously. In the Origins project, I will solve this challenge through joint integrated end-to-end analysis of multiple state-of-the-art experiments to construct a single coherent model of all main diffuse astrophysical emission processes from 1 µm to 23 GHz.

Methodology

In a novel approach, Origins will utilize archival observations from:

• ACT
• AKARI
• COBE/DIRBE
• COBE/FIRAS
• IRAS
• Planck
• WMAP

Many of these observations will be in the form of raw time-ordered data, along with upcoming measurements from Simons Observatory and SPHEREx.

Expected Outcomes

This will result in:

1. The world’s strongest and most robust constraints on primordial inflationary gravitational waves.
2. The most accurate map of CIB fluctuations published to date.
3. Possibly the world’s first map of large-scale COB fluctuations.

Simultaneously, it will redefine our understanding of thermal dust emission in the Milky Way, spanning a wide range of the electromagnetic spectrum, and will improve the precision of current models of Zodiacal Light by several orders of magnitude.

Conclusion

This Open Science project will define a new paradigm for next-generation CMB B-mode and EBL experiments.