The no-boundary measure in scalar-tensor gravity

Sahlmann H, Yeom Dh, Hwang Di (2012)

Publication Status: Published

Publication Type: Journal article, Original article

Publication year: 2012


Publisher: Institute of Physics: Hybrid Open Access

Book Volume: 29

Article Number: 095005

Journal Issue: 9

DOI: 10.1088/0264-9381/29/9/095005


In this paper, we study the no-boundary wavefunction in scalartensor gravity with various potentials for the non-minimally coupled scalar field. Our goal is to calculate probabilities for the scalar fieldand hence the effective gravitational coupling and cosmological constantto take specific values. Most calculations are performed in the minisuperspace approximation, and we use a saddle point approximation for the Euclidean action, which is then evaluated numerically. We find that for potentials that have several minima, none of them is substantially preferred by the quantum-mechanical probabilities. We argue that the same is true for the stable and the runaway solution in the case of a dilaton-type potential. Technically, this is due to the inclusion of quantum-mechanical effects (fuzzy instantons). These results are in contrast to the often-held view that vanishing gravitation or cosmological constants would be exponentially preferred in quantum cosmology, and they may be relevant to the cosmological constant problem and the dilaton stabilization problem. © 2012 IOP Publishing Ltd.

Authors with CRIS profile

How to cite


Sahlmann, H., Yeom, D.-h., & Hwang, D.-i. (2012). The no-boundary measure in scalar-tensor gravity. Classical and Quantum Gravity, 29(9).


Sahlmann, Hanno, Dong-han Yeom, and Dong-il Hwang. "The no-boundary measure in scalar-tensor gravity." Classical and Quantum Gravity 29.9 (2012).

BibTeX: Download