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Related papers: Representations of Time Coordinates in FITS

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The statistical state of any (classical or quantum) system with non-trivial time evolution can be interpreted as the pointer of a clock. The quality of such a clock is given by the statistical distinguishability of its states at different…

Quantum Physics · Physics 2007-05-23 Dominik Janzing , Thomas Beth

Conformal prediction offers a practical framework for distribution-free uncertainty quantification, providing finite-sample coverage guarantees under relatively mild assumptions on data exchangeability. However, these assumptions cease to…

Machine Learning · Statistics 2024-06-25 Derck W. E. Prinzhorn , Thijmen Nijdam , Putri A. van der Linden , Alexander Timans

A careful study is made of the operational meaning of the time symbols appearing in the space-time Lorentz transformation. Four distinct symbols, with different physical meanings, are needed to describe reciprocal measurements involving…

General Physics · Physics 2009-09-01 J. H. Field

This paper reports on ongoing research investigating more expressive approaches to spatial-temporal trajectory clustering. Spatial-temporal data is increasingly becoming universal as a result of widespread use of GPS and mobile devices,…

Databases · Computer Science 2017-12-12 Ivens Portugal , Paulo Alencar , Donald Cowan

This paper outlines the roadmap towards the redefinition of the second, which was recently updated by the CCTF Task Force created by the CCTF in 2020. The main achievements and the open challenges related to the status of the optical…

In many real-world database systems, a large fraction of the data is represented by strings: sequences of letters over some alphabet. This is because strings can easily encode data arising from different sources. It is often crucial to…

Data Structures and Algorithms · Computer Science 2024-07-17 Lorraine A. K. Ayad , Grigorios Loukides , Solon P. Pissis

Fermi coordinates are constructed as exact functions of the Schwar\-zschild coordinates around the world line of a static observer in the equatorial plane of the Schwarzschild spacetime modulo a single impact parameter determined implicitly…

General Relativity and Quantum Cosmology · Physics 2015-06-22 Donato Bini , Andrea Geralico , Robert T. Jantzen

In general relativity, the description of spacetime relies on idealised rods and clocks, which identify a reference frame. In any concrete scenario, reference frames are associated to physical systems, which are ultimately quantum in…

Quantum Physics · Physics 2021-07-28 Flaminia Giacomini

Distributed system applications rely on a fine-grain common sense of time. Existing systems maintain the common sense of time by keeping each independent machine as close as possible to wall-clock time through a combination of software…

Systems and Control · Electrical Eng. & Systems 2022-04-04 Sanjay Lall , Calin Cascaval , Martin Izzard , Tammo Spalink

Encoding and decoding models are widely used in systems, cognitive, and computational neuroscience to make sense of brain-activity data. However, the interpretation of their results requires care. Decoding models can help reveal whether…

Neurons and Cognition · Quantitative Biology 2019-04-29 Nikolaus Kriegeskorte , Pamela K. Douglas

Given the extreme accuracy of modern space astrometry, a precise relativistic modeling of observations is required. Concerning light propagation, the standard procedure is the solution of the null-geodesic equations. However, another…

General Relativity and Quantum Cosmology · Physics 2013-11-26 Stefano Bertone , Olivier Minazzoli , Mariateresa Crosta , Christophe Le Poncin-Lafitte , Alberto Vecchiato , Marie-Christine Angonin

Temporal sampling does more than add another axis to the vector of observables. Instead, under the recognition that how objects change (and move) in time speaks directly to the physics underlying astronomical phenomena, next-generation…

Astrophysics · Physics 2009-06-25 J. S. Bloom , D. L. Starr , N. R. Butler , P. Nugent , M. Rischard , D. Eads , D. Poznanski

Clock synchronization is a key function in embedded wireless systems and networks. This issue is equally important and more challenging in IoT systems nowadays, which often include heterogeneous wireless devices that follow different…

Networking and Internet Architecture · Computer Science 2022-10-03 Zihao Yu , Chengkun Jiang , Yuan He , Xiaolong Zheng , Xiuzhen Guo

Earth Observation (EO) Foundation Modelling (FM) holds great promise for simplifying and improving the use of EO data for diverse real-world tasks. However, most existing models require additional adaptation before they can be used and are…

Computer Vision and Pattern Recognition · Computer Science 2025-10-28 Samuel J. Barrett , Docko Sow

Multi-node optical clock networks will enable future studies of fundamental physics and enable applications in quantum and classical communications as well as navigation and geodesy. We implement the first ever multi-node optical clock…

The continuous advances in data collection and storage techniques allow us to observe and record real-life processes in great detail. Examples include financial transaction data, fMRI images, satellite photos, earths pollution distribution…

Methodology · Statistics 2015-02-26 Łukasz Kidziński

A time scale is a procedure for accurately and continuously marking the passage of time. It is exemplified by Coordinated Universal Time (UTC), and provides the backbone for critical navigation tools such as the Global Positioning System…

Transformer-based models have greatly pushed the boundaries of time series forecasting recently. Existing methods typically encode time series data into $\textit{patches}$ using one or a fixed set of patch lengths. This, however, could…

Machine Learning · Computer Science 2024-02-09 Linfeng Du , Ji Xin , Alex Labach , Saba Zuberi , Maksims Volkovs , Rahul G. Krishnan

Hyperatlas is an open standard intended to facilitate the large-scale federation of image-based data. The subject of hyperatlas is the space of sphere-to-plane projection mappings (the FITS-WCS information), and the standard consists of…

Astrophysics · Physics 2007-05-23 R. D. Williams , S. G. Djorgovski , M. T. Feldmann , J. C. Jacob

We extend shapelets for the analysis of galaxy images to be available in a phase space, introducing \textit{Wigner Function Shapelets (WFS)}. Whereas conventional shapelets expand images separately in configuration or Fourier space using…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-03 Shun Arai