The history of time and frequency from antiquity to the present day

IF 0.8 4区物理与天体物理 Q2 HISTORY & PHILOSOPHY OF SCIENCE

The European Physical Journal H Pub Date : 2016-03-21 DOI:10.1140/epjh/e2016-70004-3

Judah Levine

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引用次数: 3

Abstract

I will discuss the evolution of the definitions of time, time interval, and frequency from antiquity to the present day. The earliest definitions of these parameters were based on a time interval defined by widely observed apparent astronomical phenomena, so that techniques of time distribution were not necessary. With this definition, both time, as measured by clocks, and frequency, as realized by some device, were derived quantities. On the other hand, the fundamental parameter today is a frequency based on the properties of atoms, so that the situation is reversed and time and time interval are now derived quantities. I will discuss the evolution of this transition and its consequences. In addition, the international standards of both time and frequency are currently realized by combining the data from a large number of devices located at many different laboratories, and this combination depends on (and is often limited by) measurements of the times of clocks located at widely-separated laboratories. I will discuss how these measurements are performed and how the techniques have evolved over time.

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从古代到现代的时间和频率的历史

我将讨论时间、时间间隔和频率的定义从古代到现在的演变。这些参数的最早定义是基于广泛观察到的明显天文现象所定义的时间间隔，因此不需要时间分布技术。有了这个定义，时钟测量的时间和某种装置实现的频率都是推导出来的量。另一方面，今天的基本参数是基于原子性质的频率，所以情况是相反的，时间和时间间隔现在是派生量。我将讨论这种转变的演变及其后果。此外，时间和频率的国际标准目前是通过结合来自许多不同实验室的大量设备的数据来实现的，这种结合依赖于(而且往往受限于)位于相隔很远的实验室的时钟时间的测量。我将讨论如何执行这些测量以及这些技术如何随着时间的推移而发展。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

The European Physical Journal H HISTORY & PHILOSOPHY OF SCIENCE-PHYSICS, MULTIDISCIPLINARY

CiteScore

1.60

自引率

10.00%

发文量

审稿时长

>12 weeks

期刊介绍： The purpose of this journal is to catalyse, foster, and disseminate an awareness and understanding of the historical development of ideas in contemporary physics, and more generally, ideas about how Nature works. The scope explicitly includes: - Contributions addressing the history of physics and of physical ideas and concepts, the interplay of physics and mathematics as well as the natural sciences, and the history and philosophy of sciences, together with discussions of experimental ideas and designs - inasmuch as they clearly relate, and preferably add, to the understanding of modern physics. - Annotated and/or contextual translations of relevant foreign-language texts. - Careful characterisations of old and/or abandoned ideas including past mistakes and false leads, thereby helping working physicists to assess how compelling contemporary ideas may turn out to be in future, i.e. with hindsight.