Toward solving the cosmological constant problem by embedding

TL;DR

This paper proposes a mechanism to address the cosmological constant problem by embedding scalar field theories into larger frameworks, avoiding fine-tuning at tree level, with potential implications for quantum corrections.

Contribution

It introduces a generic embedding approach that dynamically fine-tunes parameters to nullify vacuum energy without fine-tuning original theory parameters.

Findings

Vacuum energy vanishes at tree level in the extended theory

No fine-tuning needed for original scalar field coupling constants

Potential extension to quantum loop corrections

Abstract

The typical scalar field theory has a cosmological constant problem. We propose a generic mechanism by which this problem is avoided at tree level by embedding the theory into a larger theory. The metric and the scalar field coupling constants in the original theory do not need to be fine-tuned, while the extra scalar field parameters and the metric associated with the extended theory are fine-tuned dynamically. Hence, no fine-tuning of parameters in the full Lagrangian is needed for the vacuum energy in the new physical system to vanish at tree level. The cosmological constant problem can be solved if the method can be extended to quantum loops.