collaborators

9 papers

astro-ph.IM2025

Learned harmonic mean estimation of the Bayesian evidence with normalizing flows

Alicja Polanska, Matthew A. Price, Davide Piras +2

We present the learned harmonic mean estimator with normalizing flows - a robust, scalable and flexible estimator of the Bayesian evidence for model comparison. Since the estimator…

astro-ph.CO2025

High-Dimensional Bayesian Model Comparison in Cosmology with GPU-accelerated Nested Sampling and Neural Emulators

Toby Lovick, David Yallup, Davide Piras +2

We demonstrate a GPU-accelerated nested sampling framework for efficient high-dimensional Bayesian inference in cosmology. Using JAX-based neural emulators and likelihoods for cosm…

astro-ph.CO2025

Transfer learning for multifidelity simulation-based inference in cosmology

Alex A. Saoulis, Davide Piras, Niall Jeffrey +3

Simulation-based inference (SBI) enables cosmological parameter estimation when closed-form likelihoods or models are unavailable. However, SBI relies on machine learning for neura…

astro-ph.CO2025

Anchors no more: Using peculiar velocities to constrain and the primordial Universe without calibrators

Davide Piras, Francesco Sorrenti, Ruth Durrer +1

We develop a novel approach to constrain the Hubble parameter and the primordial power spectrum amplitude using type Ia supernovae (SNIa) data. By considering…

astro-ph.CO2025

Constraining the primordial power spectrum using a differentiable likelihood

Subarna Chaki, Andrina Nicola, Alessio Spurio Mancini +2

The simplest inflationary models predict the primordial power spectrum (PPS) of curvature perturbations to be nearly scale-invariant. However, various other models of inflation pre…

astro-ph.CO2025

Savage-Dickey density ratio estimation with normalizing flows for Bayesian model comparison

Kiyam Lin, Alicja Polanska, Davide Piras +2

A core motivation of science is to evaluate which scientific model best explains observed data. Bayesian model comparison provides a principled statistical approach to comparing sc…