Extended Ho\v{r}ava Gravity with Physical Ground-State Wavefunction

TL;DR

This paper introduces an extended Hořava gravity model that ensures UV completion, healthy IR behavior, and a stable vacuum, addressing key issues in quantum gravity theories.

Contribution

It develops a new extended Hořava gravity framework that maintains power-counting renormalizability and stability by softly breaking detailed balance while ensuring a physical ground state.

Findings

Avoids strong coupling problem

Remains power-counting renormalizable

Has a stable vacuum state

Abstract

We propose a new extended theory of Ho\v{r}ava gravity based on the following three conditions: (i) UV completion, (ii) healthy IR behavior and (iii) a stable vacuum state in quantized version of the theory. Compared with other extended theories, we stress that any realistic theory of gravity must have physical ground states when quantization is performed. To fulfill the three conditions, we softly break the detailed balance but keep its basic structure unchanged. It turns out that the new model constructed in this way can avoid the strong coupling problem and remains power-counting renormalizable, moreover, it has a stable vacuum state by an appropriate choice of parameters.