Regularizing (away) vacuum energy

TL;DR

This paper argues that the vacuum energy density is not a physically meaningful quantity in quantum field theory, challenging its role in cosmology and quantum gravity, and suggests revising the vacuum concept to address the cosmological constant problem.

Contribution

It formulates minimal requirements for predictions in quantum field theories and demonstrates that vacuum energy density does not meet these, proposing a conceptual revision of the vacuum.

Findings

Vacuum energy density is not physically significant in the standard model.

Effective field theory regularization procedures exclude vacuum energy from physical predictions.

Revising the vacuum concept may be necessary to solve the cosmological constant problem.

Abstract

In this paper I formulate Minimal Requirements for Candidate Predictions in quantum field theories, inspired by viewing the standard model as an effective field theory. I then survey standard effective field theory regularization procedures, to see if the vacuum expectation value of energy density ($\langle\rho\rangle$) is a quantity that meets these requirements. The verdict is negative, leading to the conclusion that $\langle\rho\rangle$ is not a physically significant quantity in the standard model. Rigorous extensions of flat space quantum field theory eliminate $\langle\rho\rangle$ from their conceptual framework, indicating that it lacks physical significance in the framework of quantum field theory more broadly. This result has consequences for problems in cosmology and quantum gravity, as it suggests that the correct solution to the cosmological constant problem involves a revision of the vacuum concept within quantum field theory.