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We present Free-Range Gaussians, a multi-view reconstruction method that predicts non-pixel, non-voxel-aligned 3D Gaussians from as few as four images. This is done through flow matching over Gaussian parameters. Our generative formulation…

Computer Vision and Pattern Recognition · Computer Science 2026-04-07 Ahan Shabanov , Peter Hedman , Ethan Weber , Zhengqin Li , Denis Rozumny , Gael Le Lan , Naina Dhingra , Lei Luo , Andrea Vedaldi , Christian Richardt , Andrea Tagliasacchi , Bo Zhu , Numair Khan

The cosmic web is a complex spatial pattern of walls, filaments, cluster nodes and underdense void regions. It emerged through gravitational amplification from the Gaussian primordial density field. Here we infer analytical expressions for…

Cosmology and Nongalactic Astrophysics · Physics 2014-12-17 Job Feldbrugge , Johan Hidding , Rien van de Weygaert

The Gaussian random field (GRF) and the Gaussian Markov random field (GMRF) have been widely used to accommodate spatial dependence under the generalized linear mixed model framework. These models have limitations rooted in the symmetry and…

Methodology · Statistics 2022-12-15 Marcos O. Prates , Dipak K. Dey , Michael R. Willig , Jun Yan

The study of strong-lensing systems conventionally involves constructing a mass distribution that can reproduce the observed multiply-imaging properties. Such mass reconstructions are generically non-unique. Here, we present an alternative…

Astrophysics of Galaxies · Physics 2021-06-30 Philipp Denzel , Sampath Mukherjee , Prasenjit Saha

One of the major science goals over the coming decade is to test fundamental physics with probes of the cosmic large-scale structure out to high redshift. Here we present a fully Bayesian approach to infer the three-dimensional cosmic…

Cosmology and Nongalactic Astrophysics · Physics 2019-10-09 Natalia Porqueres , Jens Jasche , Guilhem Lavaux , Torsten Enßlin

Reconstructing the initial conditions of the universe is a key problem in cosmology. Methods based on simulating the forward evolution of the universe have provided a way to infer initial conditions consistent with present-day observations.…

Cosmology and Nongalactic Astrophysics · Physics 2023-04-11 Ronan Legin , Matthew Ho , Pablo Lemos , Laurence Perreault-Levasseur , Shirley Ho , Yashar Hezaveh , Benjamin Wandelt

Gaussian random fields are popular models for spatially varying uncertainties, arising for instance in geotechnical engineering, hydrology or image processing. A Gaussian random field is fully characterised by its mean function and…

Numerical Analysis · Mathematics 2019-02-19 Jonas Latz , Marvin Eisenberger , Elisabeth Ullmann

Gaussian random fields play an important role in many areas of science and engineering. In practice, they are often simulated by sampling from a high-dimensional multivariate normal distribution, which arises from the discretisation of a…

Numerical Analysis · Mathematics 2026-02-12 Yoshihito Kazashi , Eike H. Müller , Robert Scheichl

We introduce state-space models where the functionals of the observational and the evolutionary equations are unknown, and treated as random functions evolving with time. Thus, our model is nonparametric and generalizes the traditional…

Methodology · Statistics 2014-02-24 Anurag Ghosh , Soumalya Mukhopadhyay , Sandipan Roy , Sourabh Bhattacharya

Molecular line emissions are commonly used to trace the distribution and properties of molecular Interstellar Medium (ISM). However, the emissions are heavily blended on the Galactic disk toward the inner Galaxy because of the relatively…

Astrophysics of Galaxies · Physics 2024-10-07 Haoran Feng , Zhiwei Chen , Zhibo Jiang , James S. Urquhart

As a statistical measure to quantify the topological structure of the large-scale structure in the universe, the genus number is calculated for a number of non-Gaussian distributions in which the density field is characterized by a…

Astrophysics · Physics 2009-10-28 Takahiko Matsubara , Jun'ichi Yokoyama

Magnetic fields are present on all scales in the Universe. While we understand the processes which amplify the fields fairly well, we do not have a "natural" mechanism to generate the small initial seed fields. By using fully relativistic…

Cosmology and Nongalactic Astrophysics · Physics 2014-09-18 Ellie Nalson , Adam J. Christopherson , Karim A. Malik

General relativistic cosmology cannot be reduced to linear relativistic perturbations superposed on an isotropic and homogeneous (Friedmann-Robertson-Walker) background, even though such a simple scheme has been successfully applied to…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 Eleonora Villa , Licia Verde , Sabino Matarrese

A critical discourse is provided on the current status of the astrophysics of galaxies in view of open fundamental questions on the law of gravitation and the physics-driven variation of the galaxy-wide stellar initial mass function…

Astrophysics of Galaxies · Physics 2023-10-04 Pavel Kroupa

The relationship between the metric and nonrelativistic matter distribution depends on the theory of gravity and additional fields, providing a possible way of distinguishing competing theories. With the assumption that the geometry and…

Astrophysics · Physics 2008-10-28 Mustafa A. Amin , Robert V. Wagoner , Roger D. Blandford

We present a numerical study of the relation between the cosmic peculiar velocity field and the gravitational acceleration field. We show that on mildly non-linear scales (4-10 Mpc Gaussian smoothing), the distribution of the Cartesian…

The accelerated expansion of the universe has been widely confirmed, posing challenges to the standard $\Lambda$CDM model, particularly the cosmological coincidence problem. This has motivated the exploration of modified gravity theories,…

General Relativity and Quantum Cosmology · Physics 2025-01-03 Gaurav N. Gadbail , Sanjay Mandal , P. K. Sahoo , Kazuharu Bamba

The evolution of probability distribution functions (PDFs) of continuous density, velocity and velocity derivatives ( deformation tensor) fields in the theory of cosmological gravitational instability are considered. We show that in the…

Astrophysics · Physics 2007-05-23 Lev Kofman

We study the problem of approximate sampling from non-log-concave distributions, e.g., Gaussian mixtures, which is often challenging even in low dimensions due to their multimodality. We focus on performing this task via Markov chain Monte…

Machine Learning · Statistics 2024-05-30 Tim Tsz-Kit Lau , Han Liu , Thomas Pock

Key non-Gaussian properties of cosmological fields can be captured by their one-point statistics, providing a complement to two-point statistical measurements from power spectra or correlation functions. Large deviation theory can robustly…

Cosmology and Nongalactic Astrophysics · Physics 2023-07-31 Aoife Boyle , Alexandre Barthelemy , Sandrine Codis , Cora Uhlemann , Oliver Friedrich