L'unité de temps : directions actuelles et futures
| Autor: | S. Bize |
|---|---|
| Přispěvatelé: | Systèmes de Référence Temps Espace (SYRTE), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS) |
| Jazyk: | angličtina |
| Rok vydání: | 2019 |
| Předmět: |
Chronometric geodesy
International Atomic Time Computer science Atomic Physics (physics.atom-ph) Fontaine atomique Energy Engineering and Power Technology FOS: Physical sciences 01 natural sciences Atomic fountain Physics - Atomic Physics Unit (housing) 010309 optics Optical frequency standard Géodésie chronométrique Atomic properties Optical frequencies 0103 physical sciences Redéfinition de la seconde du SI 010306 general physics [PHYS]Physics [physics] [PHYS.PHYS.PHYS-ATOM-PH]Physics [physics]/Physics [physics]/Atomic Physics [physics.atom-ph] business.industry General Engineering Electrical engineering Metrology Orders of magnitude (time) Timescale Échelle de temps Redefinition of the SI second Fundamental physics test business [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] Realization (systems) Test de physique fondamentale Étalon de fréquence optique [PHYS.PHYS.PHYS-HIST-PH]Physics [physics]/Physics [physics]/History of Physics [physics.hist-ph] |
| Zdroj: | Comptes Rendus. Physique Comptes Rendus. Physique, Académie des sciences (Paris), 2019, 20 (1-2), pp.153-168. ⟨10.1016/j.crhy.2019.02.002⟩ |
| ISSN: | 1631-0705 1878-1535 |
| DOI: | 10.1016/j.crhy.2019.02.002⟩ |
| Popis: | Some 50~years ago, physicists, and after them the entire world, started to found their time reference on atomic properties instead of motions of the Earth that have been in use since the origin. Far from being an arrival point, this decision marked the beginning of an adventure characterized by a 6 orders of magnitude improvement in the uncertainty of realization of atomic frequency and time references. Ever progressing atomic frequency standards and time references derived from them are key resources for science and for society. We will describe how the unit of time is realized with a fractional accuracy approaching $10^{-16}$ and how it is delivered to users via the elaboration of the international atomic time. We will describe the tremendous progress of optical frequency metrology over the last 20~years which led to a novel generation of optical frequency standards with fractional uncertainties of $10^{-18}$. We will describe work toward a possible redefinition of the SI second based on such standards. We will describe existing and emerging applications of atomic frequency standards in science. Comment: 16 pages, 199 references, part of special issue of Comptes Rendus Physique "The new International System of Units" |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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