# LBNL-2016: Inflation Summary

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Jump to navigationJump to search## Status of Inflation Chapter

- Introduction
- Implications of a detection of primordial gravitational waves with CMB-S4
- The energy scale of inflation
- Planckian field ranges and symmetries
- Constraints on the graviton mass
- Following up on a detection

- Lessons from upper limits
- CMB data products and simulations to achieve goals for PGW
- Improved constraints on primordial density perturbations
- The power spectrum of primordial density perturbations
- Higher order correlations
- Isocurvature

- Constraints on curvature, cosmic birefringence, cosmic strings, axions,...
- Spatial curvature
- Cosmic Birefringence
- Cosmic Strings
- Anomalies

- Summary

## Currently needed

- Realistic forecasts for:
- tensor-to-scalar ratio (first version from Victor Buza, Colin Bischoff, John Kovac in the draft)
- tensor spectral index, running
- scalar spectral index, running
- non-Gaussianity, including BBB

- Section on isocurvature modes
- Additional discussion on bispectrum
- Discussion of trispectrum
- Streamline various sections

## Open questions

Bigger picture questions

- Should the inflation chapter be thought of as independent at some level? If so, it should likely include higher level discussion
- CMB-S4 can only reach theoretically well motivated thresholds for r. As a consequence r is the main inflationary driver of the design, and the chapter is focused on primordial gravitational waves. Other aspects imply CMB-S4 will have high angular resolution. Should the discussion of constraints on the power spectrum, bispectrum,... be expanded?
- Should the inflation chapter be focused on inflation or include implications of high-scale inflation for other areas of fundamental physics?

More detailed questions

- How much time and effort should be spent on strawman models that produce B-mode power in excess of the inflationary signal?
- Should various sections be moved or remain in the inflation chapter?
- Constraints on the graviton
- Birefringence