59 citations · 103 across the 16 of their papers we have counts for
18 papers
On the foundations of anthropic reasoning: Implications for life across the universe
Brendon J. Brewer, Geraint F. Lewis, Jesse Goodman
With only one confirmed example, namely the Earth, the abundance of life across the universe remains deeply uncertain, and local evidence about Earth's particular circumstances can…
Algorithmic bottlenecks in evolution: Genetic code, symbolic language, and the Great Filter hypothesis
Mikhail Prokopenko, Nihat Ay, Angelica Breviario +12
The Great Filter hypothesis proposes that the emergence of technological societies capable of interstellar travel depends on a small number of exceptionally hard and highly improba…
Wising up to CatWISE: using simulation-based inference to interpret the ecliptic bias and confirm the cosmic dipole excess
Oliver T. Oayda, Geraint F. Lewis
We apply Simulation-Based Inference ('SBI') to the cosmic dipole problem for the first time, measuring the distribution of quasar counts over the sky in the CatWISE2020 ('CatWISE')…
Local environmental dependence on weak-lensing shear statistics
Sonia Akter Ema, Md Rasel Hossen, Krzysztof Bolejko +1
Despite the assumption that an ideal FLRW observer is not dependent on the local environment, observations are biased by the positions of the observers due to the matter correlatio…
Cosmic Multipoles in Galaxy Surveys II: Comparing Different Methods in Assessing the Cosmic Dipole
Vasudev Mittal, Oliver T. Oayda, Geraint F. Lewis
We present a comparative analysis of estimators and Bayesian methods for determining the number count dipole from cosmological surveys. The increase in discordance between the numb…
Streams and Shells Decoded: A Density-Driven Approach to Stellar Clustering in Galactic Halos with AstroLink
Viraj Ekanayaka, Smrithi Gireesh Babu, William H. Oliver +1
We present a novel method to differentiate stream-like and shell-like tidal remnants of stellar systems in galactic halos using the density-based approach of the clustering algorit…
Revisiting The Cosmological Time Dilation of Distant Quasars: Influence of Source Properties and Evolution
Brendon J. Brewer, Geraint F. Lewis, Yuan Li
After decades of searching, cosmological time dilation was recently identified in the timescale of variability seen in distant quasars. Here, we expand on the previous analysis to…
Cosmic Multipoles in Galaxy Surveys Part I: How Inferences Depend on Source Counts and Masks
Oliver T. Oayda, Vasudev Mittal, Geraint F. Lewis
We present a new approach to constructing and fitting dipoles and higher-order multipoles in synthetic galaxy samples over the sky. Within our Bayesian paradigm, we illustrate that…
Biological arrow of time: Emergence of tangled information hierarchies and self-modelling dynamics
Mikhail Prokopenko, Paul C. W. Davies, Michael Harré +6
We study open-ended evolution by focusing on computational and information-processing dynamics underlying major evolutionary transitions. In doing so, we consider biological organi…
A Bayesian approach to the cosmic dipole in radio galaxy surveys: Joint analysis of NVSS & RACS
Oliver T. Oayda, Vasudev Mittal, Geraint F. Lewis +1
We examine the sky distribution of radio galaxies in the NRAO VLA Sky Survey (NVSS) and the Rapid ASKAP Continuum Survey (RACS). Analyses of these samples have reported tension bet…
The Hierarchical Structure of Galactic Haloes: Differentiating Clusters from Stochastic Clumping with AstroLink
William H. Oliver, Pascal J. Elahi, Geraint F. Lewis +1
We present AstroLink, an efficient and versatile clustering algorithm designed to hierarchically classify astrophysically-relevant structures from both synthetic and observational…
The Cosmic Dipole in the Quaia Sample of Quasars: A Bayesian Analysis
Vasudev Mittal, Oliver T. Oayda, Geraint F. Lewis
We present a Bayesian analysis of the Quaia sample of 1.3 million quasars as a test of the cosmological principle. This principle postulates that the universe is homogeneous and is…
Multiverse Predictions for Habitability: Origin of Life Scenarios
McCullen Sandora, Vladimir Airapetian, Luke Barnes +2
If the origin of life is rare and sensitive to the local conditions at the site of its emergence, then, using the principle of mediocrity within a multiverse framework, we may expe…
Multiverse Predictions for Habitability: Planetary Characteristics
McCullen Sandora, Vladimir Airapetian, Luke Barnes +1
Recent detections of potentially habitable exoplanets around sunlike stars demand increased exploration of the physical conditions that can sustain life, by whatever methods availa…
Multiverse Predictions for Habitability: Element Abundances
McCullen Sandora, Vladimir Airapetian, Luke Barnes +2
We investigate the dependence of elemental abundances on physical constants, and the implications this has for the distribution of complex life for various proposed habitability cr…
Big Bang Nucleosynthesis Initial Conditions: Revisiting Wagoner et al. (1967)
Charlie Sharpe, Geraint F. Lewis, Luke A. Barnes
We revisit Wagoner et al. (1967), a classic contribution in the development of Big Bang Nucleosynthesis. We demonstrate that it presents an incorrect expression for the temperature…
The Trouble with "Puddle Thinking": A User's Guide to the Anthropic Principle
Geraint F. Lewis, Luke A. Barnes
Are some cosmologists trying to return human beings to the centre of the cosmos? In the view of some critics, the so-called "anthropic principle" is a desperate attempt to salvage…
Nonlinear Chaplygin Gas Cosmologies
P. P. Avelino, K. Bolejko, G. F. Lewis
We study the nonlinear regime of Unified Dark Energy models, using Generalized Chaplygin Gas cosmologies as a representative example, and introduce a new parameter characterizing t…