6 papers
Coupled quintessence from an axion dark sector
Rayff de Souza, Edmund J. Copeland, Jailson Alcaniz
Recent observational data arising from the DESI collaboration has hinted at a possible departure from the standard CDM cosmological model, preferring instead the presence of a d…
CMB anisotropies from cosmic (super)strings in light of ACT DR6
Juhan Raidal, Anastasios Avgoustidis, Edmund Copeland +1
We present updated constraints on cosmic string and superstring parameters derived from Cosmic Microwave Background (CMB) anisotropies. The constraints are obtained via Markov Chai…
The Revised Evolutionary Volume Tolman Test: Cosmological Constraints from Galaxy Evolution
Christopher J. Conselice, Edmund J. Copeland, Sergio Sevillano Muñoz
In this study we adapt a classical cosmology measurement, the volume or number density test, to a modern synthesis of observed galaxy evolution. We do this by using measured galaxy…
Dynamical Systems and Superstring Phases in the Early Universe
Noelia Sánchez González, Joseph P. Conlon, Edmund J. Copeland +1
We study the string theory dynamics of the volume scalar rolling down an exponential potential during the period between inflation and reheating, in a background of cosmic superstr…
Self-Tracking Solutions for Asymptotic Scalar Fields
Martin Mosny, Joseph P. Conlon, Edmund J. Copeland
We explore the dynamics of pure scalar fields rolling on an exponential potential in the absence of any additional background fluid and demonstrate the existence of self-tracking s…
Accelerated cosmological expansion from pseudo-Hermiticity
Edmund J. Copeland, Andrei Lazanu, Peter Millington +1
We show that a well-studied pseudo-Hermitian field theory composed of two complex scalar fields can generate accelerated cosmological expansion through a novel mechanism. The dynam…