collaborators

6 papers

astro-ph.CO2026

Impact of inhomogeneous curvature on growth rate measurements from magnitude fluctuations

Andrew Nguyen, Chris Blake, Hayley J. Macpherson

Our interpretation of current cosmological observations rests on the assumptions of homogeneity and isotropy, leading to uniform background curvature and expansion characterised by…

astro-ph.CO2026

On the potential for inhomogeneities to mimic an evolving dark energy

Hayley J. Macpherson, Georgios Valogiannis

In this work we explore the ability of inhomogeneities to result in an apparent dynamical evolution of dark energy. The idea that inhomogeneities may alter the expansion history of…

astro-ph.CO2026

Large-scale weak lensing convergence in nonlinear general relativity

Hayley J. Macpherson

In this work we investigate the weak lensing convergence using an end-to-end nonlinear general relativistic framework. Combining numerical relativity simulations of large-scale str…

astro-ph.CO2025

A theoretical prediction for the dipole in nearby distances using cosmography

Hayley J. Macpherson, Asta Heinesen

Cosmography is a widely applied method to infer kinematics of the Universe at small cosmological scales while remaining agnostic about the theory of gravity at play. Usually cosmol…

astro-ph.CO2025

The Effect of Nonlinear Gravity on the Cosmological Background During Preheating

Ryn Grutkoski, Hayley J. Macpherson, John T. Giblin +1

We use numerical relativity to study the violent preheating era at the end of inflation. This epoch can result in highly nonlinear fluctuations in density and gravitational potenti…

astro-ph.CO2024

First investigation of void statistics in numerical relativity simulations

Michael J. Williams, Hayley J. Macpherson, David L. Wiltshire +1

We apply and extend standard tools for void statistics to cosmological simulations that solve Einstein's equations with numerical relativity (NR). We obtain a simulated void catalo…