arXiv:2606. 07771v1 Announce Type: cross Abstract: Foundation models for astronomical surveys offer powerful learned representations that can be transferred to downstream regression tasks such as galaxy property estimation.
By Karla Tame-Narvaez, Aleksandra \'Ciprijanovi\'c, Shubhendu Trivedi
arXiv:2609.38312v1 Announce Type: cross
Abstract: The Platonic Representation Hypothesis predicts that sufficiently scaled foundation models converge on a shared representation of the world. As each...
By Michael J. Smith, Shashwat Sourav
The paper presents a probabilistic machine‑learning framework for classifying low‑ and high‑resolution stellar and extragalactic spectra, targeting the upcoming 4MOST survey. Four approaches were evaluated—CNNs, Dirichlet distribution, Monte Carlo dropout (MCD), and Bayesian neural networks with variational inference—using SDSS data and a 4MOST mock dataset. The MCD‑augmented CNN achieved the highest accuracies (92.6% on SDSS, 93.9% on mock data) while also delivering well‑calibrated uncertainty estimates with minimal extra computational cost.
By Simon Barton, Martin Sahl\'en, Andreas Korn, Christian Glaser
arXiv:2512. 10222v2 Announce Type: replace-cross Abstract: Semi-analytic models are a widely used approach to simulate galaxy properties within a cosmological framework, relying on simplified yet physically motivated prescriptions.
By Natal\'i S. M. de Santi, Francisco Villaescusa-Navarro, Pablo Araya-Araya, Gabriella De Lucia, Fabio Fontanot, Lucia A. Perez, Manuel Arn\'es-Curto, Violeta Gonzalez-Perez, \'Angel Chandro-G\'omez, Rachel S. Somerville, Tiago Castro
The paper introduces a method for estimating uncertainty in hierarchical taxonomic reasoning produced by black‑box large language models (LLMs). By extracting proxy features with an open‑source tool and training lightweight supervised estimators that incorporate hierarchy‑aware supervision, the authors predict rank‑wise correctness. Across three LLMs, these estimators outperform token‑likelihood baselines, raising micro AUROC from 0.57 to 0.75–0.80, with a rank‑specific multi‑head design delivering the best results.
By Shuting Xie, Nathaniel Lesperance, Graham W. Taylor
The paper presents a spectral hierarchy for classifying the cosmic web by applying scale-weighting kernels to the density field before using eigenvalue-based methods. This framework unifies existing web definitions—potential/tidal, curvature-based, and higher-derivative levels—into a single, interpretable hierarchy that captures structure from large to small scales. The authors quantify the hierarchy’s information content by correlating a web contrast field with halo distributions, showing that it retains significant tracer-relevant information across scales, especially at nonlinear levels.
By Francisco-Shu Kitaura, Francesco Sinigaglia