Chronology

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(General) Chronology is the science of locating events in time. An arrangement of events, from either earliest to latest or the reverse, is also called a chronology or, particularly when involving graphical elements, a timeline. See also Chronicle.

1 Definition
2 See also
3 External links
4 Further reading

[edit] Definition

Unlike chronometry (i.e. timekeeping), which is part of physics, chronology, as the science of localizing historical events in time, is part of history.

The familiar terms ‘era’ (taken as a system of numbered calendar years) and ‘calendar’ concern two complementary fundamental concepts of chronology. So during eight centuries the calendar belonging to the Christian era, which era was taken in use in the eighth century, was the Julian calendar, but after the year 1582 it was the Gregorian calendar. Dionysius Exiguus (about the year 500) was the founder.

A chronology may be either relative—that is, locating related events relative to each other—or absolute—locating these events to specific dates in a Chronological Era. In that these dates are themselves events, the difference between the two blurs a little: an absolute chronology just includes a strange sort of event called a date which is common to all absolute chronologies covering the same period of time. Even this distinction may be blurred by use of different calendars; in Judeo-Christian cultures, historical dates in an absolute chronology are understood to be referred to the Christian era in combination with the Gregorian calendar.

Other familiar chronological subjects are for example: linear timescale, French revolutionary era, leap year, jewish calendar. Subjects of the Christian chronology are for example: Dionysius Exiguus' easter table, Paschal full moon, lunar cycle, solar cycle, easter cycle, lunar phase number, millennium question.

In the absence of written history, with its chronicles and king lists, late 19th century archaeologists found that they could develop relative chronologies based on pottery techniques and styles. In the field of Egyptology, William Flinders Petrie pioneered sequence dating to penetrate pre-dynastic Neolithic times, using groups of contemporary artefacts deposited together at a single time in graves and working backwards methodically from the earliest historical phases of Egypt. Compare the American technique of Seriation.

Known wares discovered at strata in sometimes quite distant sites, the product of trade, helped extend the network of chronologies. Some cultures have retained the name applied to them in reference to characteristic forms, for lack of an idea of what they called themselves: "The Beaker People" in northern Europe during the 3rd millennium BCE, for example. The study of the means of placing pottery and other cultural artifacts into some kind of order proceeds in two phases, classification and typology: Classification creates categories for the purposes of description, and typology seeks to identify and analyse changes that allow artifacts to be placed into sequences [1].

Laboratory techniques developed particularly after mid-20th century helped constantly revise and refine the chronologies developed for specific cultural areas. Unrelated dating methods help reinforce a chronology, an axiom of corroborative evidence. Ideally, archaeological materials used for dating a site should complement each other and provide a means of cross-checking. Conclusions drawn from just one unsupported technique are usually regarded as unreliable.

Bayesian analysis has recently started to be routinely applied in the analysis of chronological information, including radiocarbon-derived dates,

Several legendary sources tend to assign unrealistically long lifespans to pre-historical heroes and monarchs (e.g Egypt, Hebrews, Japanese), if the number of years there reported are understood as years of more than 340 days. One potent explanation for this has been that there have been more than one harvest during the actual year, and memories evolving to legends tend to count each growth period as separate year.

Though chronologies formulated before the 1960s are subject to serious skepticism today, more recent results are more robust than readily appears to journalists and enthusiastic amateurs.