Screening of scalar fields in Dirac-Born-Infeld theory

Burrage, Clare; Khoury, Justin

Abstract

We study a new screening mechanism which is present in Dirac-Born-Infeld (DBI)-like theories. A scalar field with a DBI-like Lagrangian is minimally coupled to matter. In the vicinity of sufficiently dense sources, nonlinearities in the scalar dominate and result in an approximately constant acceleration on a test particle, thereby suppressing the scalar force relative to gravity. Unlike generic P(X) or chameleon theories, screening happens within the regime of validity of the effective field theory thanks to the DBI symmetry. We derive an exact form for the field profile around multiple sources and determine the constraints on the theory parameters from tests of gravity. Perturbations around the spherically-symmetric background propagate superluminally, but we argue for a chronology protection analogous to Galileons. This is the first example of a screening mechanism for which quantum corrections to the theory are under control and exact solutions to cosmological N-body problems can be found.

Citation

Burrage, C., & Khoury, J. (2014). Screening of scalar fields in Dirac-Born-Infeld theory. Physical Review D, D90(2), Article 024001. https://doi.org/10.1103/PhysRevD.90.024001

• Journal Article Type: Article
• Acceptance Date: Jul 1, 2014
• Publication Date: Jul 1, 2014
• Deposit Date: Apr 20, 2017
• Publicly Available Date: Apr 20, 2017
• Journal: Physical Review D
• Print ISSN: 2470-0010
• Electronic ISSN: 2470-0029
• Publisher: American Physical Society
• Peer Reviewed: Peer Reviewed
• Volume: D90
• Issue: 2
• Article Number: 024001
• DOI: https://doi.org/10.1103/PhysRevD.90.024001
• Public URL: https://nottingham-repository.worktribe.com/output/729401
• Publisher URL: https://journals.aps.org/prd/abstract/10.1103/PhysRevD.90.024001
• Contract Date: Apr 20, 2017