A Lapse in the Cosmological Constant Problem

TL;DR

This paper introduces a novel higher-dimensional gravitational mechanism inspired by Horava-Lifshitz gravity that addresses the cosmological constant problem by globally constraining 4D geometry, canceling vacuum energy contributions.

Contribution

It proposes a new approach using a 5D anisotropic spacetime with a lapse-induced global constraint, extending vacuum energy sequestering ideas.

Findings

Radiative vacuum energy contributions are canceled at all orders.

The mechanism operates in a 5D spacetime with anisotropic scaling.

Effective gravitational equations differ from standard sequestering.

Abstract

We present a new mechanism for addressing the cosmological constant problem based on global constraints arising from a lapse function in a higher-dimensional gravitational theory. Inspired by Horava-Lifshitz gravity, we consider a 5d spacetime with anisotropic scaling along a compact extra dimension, while preserving Lorentz invariance in four dimensions. In the deep infrared limit, variation with respect to the lapse generates a global constraint on the 4d geometry, closely analogous to that of vacuum energy sequestering. Although the resulting effective gravitational equations differ from standard sequestering, radiative contributions to the Standard Model vacuum energy are nevertheless cancelled at all orders.