Another look at Absolute and Relative Scales 

Time and Calendars

Time can be expressed in using relative or absolute scales. We use a relative scale because it is convenient.


Our calendar is based on the time it takes the Earth to revolve around the Sun. A Eurocentric/Christian bias has resulted in the year 0 being assigned to the year in which a religious icon was born. Negative years are written as years BC (some people use the term BCE for Before Common Era).

In the lunar calandecalar the length of the year is determined be the cycles of the moon. So, the unit with which a year is measured in the lunar calendar would be different than the length of a solar year.


An absolute scale could also be used to measure time. Time can be measured in any unit so the length our year is commonly used, but the year 0 is not defined arbitrarily. In an absolute calendar the year 0 is the year the universe began.


Thus the date of an event can be determined using relative scales such as a Lunar calendar or a Solar calendar (with the year zero defined based on a historical event), or the date of an event can be determined using an absoute scale; a calendar based on the Solar year with the time 0 being the creation of the universe.


The first two calendars are like Fahrenheit and Celsius. The last calendar is like Kelvin.


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