Editing Time (section)

{{Short description|Continuous progression from past to future}}
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{{Not to be confused with|Thyme}}
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'''Time''' is the continuous progression of [[existence]] that occurs in an apparently [[irreversible process|irreversible]] succession from the [[past]], through the [[present]], and into the [[future]].<ref>
{{cite dictionary |url=http://oxforddictionaries.com/definition/time |title=Time |dictionary=Oxford Dictionaries |quote=The indefinite continued progress of existence and events in the past, present, and future regarded as a whole |publisher=Oxford University Press |access-date=18 May 2017 |url-status=dead |archive-url=https://web.archive.org/web/20120704084938/http://oxforddictionaries.com/definition/time |archive-date=4 July 2012}}</ref><ref name=DefRefs02/><ref>{{Cite dictionary |url=http://ahdictionary.com/word/search.html?q=time |title=Time |dictionary=The American Heritage Dictionary of the English Language |edition=Fourth |date=2011 |quote=A nonspatial continuum in which events occur in apparently irreversible succession from the past through the present to the future.|url-status=live |archive-url=http://archive.wikiwix.com/cache/20120719114813/http://ahdictionary.com/word/search.html?q=time |archive-date=19 July 2012}}</ref> It is a component quantity of various measurements used to [[sequence]] events, to compare the duration of events (or the intervals between them), and to quantify [[rates of change]] of quantities in material reality or in the [[qualia|conscious experience]].<ref>[http://www.merriam-webster.com/dictionary/time Merriam-Webster Dictionary] {{webarchive|url=https://web.archive.org/web/20120508031242/http://www.merriam-webster.com/dictionary/time |date=8 May 2012 }} the measured or measurable period during which an action, process, or condition exists or continues: duration; a nonspatial continuum which is measured in terms of events that succeed one another from past through present to future</ref><ref>Compact [[Oxford English Dictionary]] A limited stretch or space of continued existence, as the interval between two successive events or acts, or the period through which an action, condition, or state continues. (1971).</ref><ref name=DefRefs01/><ref name=Poidevin/> Time is often referred to as a fourth [[dimension]], along with [[Three-dimensional space|three spatial dimensions]].<ref>"Newton did for time what the Greek geometers did for space, idealized it into an exactly measurable dimension." ''About Time: Einstein's Unfinished Revolution'', Paul Davies, p. 31, Simon & Schuster, 1996, {{isbn|978-0-684-81822-1}}
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Time is one of the seven fundamental [[physical quantities]] in both the [[International System of Units]] (SI) and [[International System of Quantities]]. The SI base [[unit of time]] is the [[second]], which is defined by measuring the [[electronic transition]] frequency of [[caesium]] atoms. [[General relativity]] is the primary framework for understanding how [[spacetime]] works.<ref>{{cite book |title=Partial Differential Equations in General Relativity |edition=illustrated |first1=Alan D. |last1=Rendall |publisher=Oxford University Press |year=2008 |isbn=978-0-19-921540-9 |page=9 |url=https://books.google.com/books?id=CPkaAQAAIAAJ}}</ref> Through advances in both theoretical and experimental investigations of spacetime, it has been shown that time can be distorted and [[Time dilation|dilated]], particularly at the edges of [[black hole]]s.

Throughout history, time has been an important subject of study in religion, philosophy, and science. Temporal measurement has occupied scientists and [[Engineering technologist|technologists]], and has been a prime motivation in navigation and astronomy. Time is also of significant social importance, having economic value ("[[Time value of money|time is money]]") as well as personal value, due to an awareness of the limited time in each [[day]] ("''[[carpe diem]]''") and in [[life expectancy|human life spans]].