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When modeling global satellite data to recover a planetary magnetic or gravitational potential field and evaluate it elsewhere, the method of choice remains their analysis in terms of spherical harmonics. When only regional data are…

Geophysics · Physics 2017-10-11 Alain Plattner , Frederik J. Simons

Spectra of quasars result primarily from interactions of natural light with atomic hydrogen. A visible absorption of a sharp and saturated spectral line in a gas requires a low pressure, so a long path without blushing as a cosmological…

Instrumentation and Methods for Astrophysics · Physics 2015-12-31 Jacques Moret-Bailly

In their Letter [Phys. Rev. Lett. 92, 121302 (2004)] (also [Astron. Astrophys. 417, 853 (2004)]), Srianand et al. analysed optical spectra of heavy-element species in 23 absorption systems along background quasar sight-lines, reporting…

Astrophysics · Physics 2009-06-23 Michael T. Murphy , John K. Webb , Victor V. Flambaum

Performing Data Assimilation (DA) at a low cost is of prime concern in Earth system modeling, particularly at the time of big data where huge quantities of observations are available. Capitalizing on the ability of Neural Networks…

Machine Learning · Computer Science 2021-11-24 Mathis Peyron , Anthony Fillion , Selime Gürol , Victor Marchais , Serge Gratton , Pierre Boudier , Gael Goret

Solving tough clinical questions that require both image and text understanding is still a major challenge in healthcare AI. In this work, we propose Q-FSRU, a new model that combines Frequency Spectrum Representation and Fusion (FSRU) with…

Computer Vision and Pattern Recognition · Computer Science 2025-10-06 Rakesh Thakur , Yusra Tariq , Rakesh Chandra Joshi

An artificial intelligence (AI) model can be viewed as a function that maps inputs to outputs in high-dimensional spaces. Once designed and well trained, the AI model is applied for inference. However, even optimized AI models can produce…

Artificial Intelligence · Computer Science 2026-02-27 Sha Hu

Artificial intelligence (AI) and large language models (LLM) are reshaping science, with most recent advances culminating in fully-automated scientific discovery pipelines. But qualitative research has been left behind. Researchers in…

Artificial Intelligence · Computer Science 2025-11-13 Stine Beltoft , Lukas Galke

We present a new method for inferring photometric redshifts in deep galaxy and quasar surveys, based on a data driven model of latent spectral energy distributions (SEDs) and a physical model of photometric fluxes as a function of redshift.…

Cosmology and Nongalactic Astrophysics · Physics 2017-03-29 Boris Leistedt , David W. Hogg

Advances in optical astrometry allow us to infer the non-radial kinematic structure of the Universe directly from observations. Here I use a supervised machine learning neural network method to predict 1.57 million redshifts based on…

Astrophysics of Galaxies · Physics 2025-07-03 Valeri V. Makarov

ESPRESSO is an extremely stable high-resolution spectrograph which is currently being developed for the ESO VLT. With its groundbreaking characteristics it is aimed to be a "science machine", i.e. a fully-integrated instrument to directly…

We introduce a machine-learning-based approach to enhance the sensitivity of optical-extreme ultraviolet (XUV) transient absorption spectroscopy. A reference spectrum is used as input to a three-layer feed-forward neural network, allowing…

Optics · Physics 2023-05-04 Tobias Heinrich , Hung-Tzu Chang , Sergey Zayko , Murat Sivis , Claus Ropers

In the near future, new surveys promise a significant increase in the number of quasars (QSO) at large redshifts. This will help to constrain the dark energy models using quasars. The Large Synoptic Survey Telescope (LSST) will cover over…

Astrophysics of Galaxies · Physics 2019-10-08 Mary Loli Martínez-Aldama , Swayamtrupta Panda , Bożena Czerny , Michal Zajaček

In characterization of quantum systems, adapting measurement settings based on data while it is collected can generally outperform in efficiency conventional measurements that are carried out independently of data. The existing methods for…

Quantum Physics · Physics 2016-11-21 Markku P. V. Stenberg , Frank K. Wilhelm

The spectrograph ESPRESSO recently obtained a limit on the variation of the fine-structure constant, $\alpha$, through measurements along the line of sight of a bright quasar with a precision of $1.36$ ppm at $1\sigma$ level. This imposes…

We introduce an increasing-complexity, open-ended, and human-agnostic metric to evaluate foundational and frontier AI models in the context of Artificial General Intelligence (AGI) and Artificial Super Intelligence (ASI) claims. Unlike…

Artificial Intelligence · Computer Science 2026-02-13 Alberto Hernández-Espinosa , Luan Ozelim , Felipe S. Abrahão , Hector Zenil

The cosmic curvature, a fundamental parameter for cosmology could hold deep clues to inflation and cosmic origins. We propose an improved model-independent method to constrain the cosmic curvature by combining the constructed Hubble diagram…

Cosmology and Nongalactic Astrophysics · Physics 2024-02-19 Tonghua Liu , Shuo Cao , Jia Zhang , Marek Biesiada , Yuting Liu , Yujie Lian

The most precise method of investigating possible space-time variations of the fine-structure constant, using high-redshift quasar absorption lines, is the many-multiplet (MM) method. For reliable results this method requires very accurate…

Astrophysics · Physics 2009-11-11 M. Aldenius , S. Johansson , M. T. Murphy

Using two trapped ion species ($\rm{^{27}Al^+}$ and $\rm{^9Be^+}$) as primary and ancillary systems, we implement qubit measurements based on the repetitive transfer of information and quantum nondemolition detection. The repetition…

Quantum Physics · Physics 2007-05-23 D. B. Hume , T. Rosenband , D. J. Wineland

With the construction of the VLTI (Very Large Telescope Interferometer of the European Observatory ESO for the southern hemisphere) it is now possible to make observations with resolutions of the order of milli-arc-seconds, especially in IR…

Solar and Stellar Astrophysics · Physics 2017-09-22 M. Hadjara

In this paper, a novel and robust algorithm is proposed for adaptive beamforming based on the idea of reconstructing the autocorrelation sequence (ACS) of a random process from a set of measured data. This is obtained from the first column…

Information Theory · Computer Science 2021-06-25 Saeed Mohammadzadeh , Vitor H. Nascimento , Rodrigo C. de Lamare , Osman Kukrer
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