35 citations · 139 across the 15 of their papers we have counts for
16 papers
Accelerating systems as probes of Lorentz violation
Quentin G. Bailey, Nils A. Nilsson, Sawyer J. Star
We investigate the Fulling-Davies-Unruh effect in a local Lorentz-violating effective field theory, focusing on the quantum-field response of accelerated detectors. We canonically…
Classical radiation fields for scalar, electromagnetic, and gravitational waves with spacetime-symmetry breaking
Quentin G. Bailey, Alexander S. Gard, Nils A. Nilsson +2
An effective field theory framework is used to investigate some Lorentz-violating effects on the generation of electromagnetic and gravitational waves, complementing previous work…
Spacetime-symmetry breaking effects in gravitational-wave generation at the first post-Newtonian order
Nils A. Nilsson, Christophe Le-Poncin Lafitte
Current searches for signals of departures from the fundamental symmetries of General Relativity using gravitational waves are largely dominated by propagation effects like dispers…
Dynamical dark energy from spacetime-symmetry breaking -- late-time behaviour and phantom crossing
Nils A. Nilsson
We investigate the late-time cosmological dynamics in a simple case of explicit spacetime-symmetry breaking. By expanding in a small symmetry-breaking coefficient we are able to wr…
On the energy flow of in Hořava-Lifshitz cosmology
Ewa Czuchry, Nils A. Nilsson
Hořava-Lifshitz gravity has been proposed as a ghost-free quantum gravity model candidate with an anisotropic UV-scaling between space and time. We present here a cosmological back…
A New Test of Dynamical Dark Energy Models and Cosmic Tensions in Hořava Gravity
Eleonora Di Valentino, Nils A. Nilsson, Mu-In Park
Horava gravity has been proposed as a renormalizable, higher-derivative, Lorentz-violating quantum gravity model without ghost problems. A Horava gravity based dark energy (HDE) mo…
Induced cosmological anisotropy by a gauge-gravity interaction
Bum-Hoon Lee, Hochoel Lee, Wonwoo Lee +2
We present a simple model which generates cosmological anisotropies on top of standard FLRW geometry. This is in some sense reminiscent of the mean field approximation, where the m…
SME Gravity in the Early Universe
Nils A. Nilsson
In this talk, we give a short overview of recent work on cosmological solutions within the SME gravitational sector under the assumption of explicit spacetime-symmetry breaking. We…
Explicit spacetime-symmetry breaking and the dynamics of primordial fields
Nils A. Nilsson
We study the effects of explicit spacetime-symmetry breaking on primordial tensor fluctuations using an effective-field theory for Lorentz/CPT violation. We find that the graviton…
Tests of Standard Cosmology in Horava Gravity and Bayesian Evidence for a Closed Universe, and the Hubble Tension
Nils A. Nilsson, Mu-In Park
We consider some background tests of standard cosmology in the context of Horava gravity with different scaling dimensions for space and time, which has been proposed as a renormal…
3+1 Formulation of the Standard-Model Extension Gravity Sector
Kellie O'Neal-Ault, Quentin G. Bailey, Nils A. Nilsson
We present a 3+1 formulation of the effective field theory framework called the Standard-Model Extension in the gravitational sector. The explicit local Lorentz and diffeomorphism…
Preferred-frame Effects, the Tension, and Probes of Hořava-Lifshitz Gravity
Nils A. Nilsson
We discuss implications on the tension due to preferred-frame effects in the context of Hořava-Lifshitz gravity. By using a combination of low-redshift data (Sne1a, elliptica…
A 3+1 Decomposition of the Minimal Standard-Model Extension Gravitational Sector
Nils A. Nilsson, Kellie O'Neal-Ault, Quentin G. Bailey
The 3+1 (ADM) formulation of General Relativity is used in, for example, canonical quantum gravity and numerical relativity. Here we present a 3+1 decomposition of the minimal Stan…
Cosmology in a toy model of Lorentz breaking gravity
Nils A. Nilsson, Mariusz P. Dabrowski
We explore cosmological solutions to Lorentz breaking gravity using the gravitational sector of the Standard Model Extension (SME). By using a simple toy model for Lorentz violatio…
Hořava-Lifshitz cosmology in light of new data
Nils A. Nilsson, Ewa Czuchry
We present new observational constraints on Lorentz violating Hořava-Lifshitz cosmological scenarios using an updated cosmological data set from Cosmic Microwave Background (Planck…
Energy Scale of Lorentz Violation in Rainbow Gravity
Nils A. Nilsson, Mariusz P. Dabrowski
We modify the standard relativistic dispersion relation in a way which breaks Lorentz symmetry - the effect is predicted in a high-energy regime of some modern theories of quantum…