Editing Dimension (section)

===Time<!--'Temporal dimension' and 'Temporal dimensions' redirect here-->===
A '''temporal dimension''', or '''time dimension''',<!--boldface per WP:R#PLA--> is a dimension of time. Time is often referred to as the "[[Spacetime|fourth dimension]]" for this reason, but that is not to imply that it is a spatial dimension{{citation needed|date=February 2024}}. A temporal dimension is one way to measure physical change. It is perceived differently from the three spatial dimensions in that there is only one of it, and that we cannot move freely in time but subjectively move [[Arrow of time|in one direction]].

The equations used in physics to model reality do not treat time in the same way that humans commonly perceive it. The equations of [[classical mechanics]] are [[T-symmetry|symmetric with respect to time]], and equations of quantum mechanics are typically symmetric if both time and other quantities (such as [[C-symmetry|charge]] and [[Parity (physics)|parity]]) are reversed. In these models, the perception of time flowing in one direction is an artifact of the [[laws of thermodynamics]] (we perceive time as flowing in the direction of increasing [[entropy]]).

The best-known treatment of time as a dimension is [[Henri Poincaré|Poincaré]] and [[Albert Einstein|Einstein]]'s [[special relativity]] (and extended to [[general relativity]]), which treats perceived space and time as components of a four-dimensional [[manifold]], known as [[spacetime]], and in the special, flat case as [[Minkowski space]]. Time is different from other spatial dimensions as time operates in all spatial dimensions. Time operates in the first, second and third as well as theoretical spatial dimensions such as a [[Four-dimensional space|fourth spatial dimension]]. Time is not however present in a single point of absolute infinite [[Singularity (mathematics)|singularity]] as defined as a [[geometric point]], as an infinitely small point can have no change and therefore no time. Just as when an object moves through [[Position (geometry)|positions]] in space, it also moves through positions in time. In this sense the [[force]] moving any [[Physical object|object]] to change is ''time''.<ref>{{cite arXiv| eprint = math/0702552| last1 = Rylov| first1 = Yuri A.| title = Non-Euclidean method of the generalized geometry construction and its application to space-time geometry| year = 2007}}</ref><ref>{{Cite book|chapter-url=https://link.springer.com/chapter/10.1007/978-3-319-17046-6_8|chapter=Definitions for The Fourth Dimension: A Proposed Time Classification System1|first1=Paul M.|last1=Lane|first2=Jay D.|last2=Lindquist|title=Proceedings of the 1988 Academy of Marketing Science (AMS) Annual Conference|series=Developments in Marketing Science: Proceedings of the Academy of Marketing Science|editor-first=Kenneth D.|editor-last=Bahn|date=May 22, 2015|publisher=Springer International Publishing|pages=38–46|via=Springer Link|doi=10.1007/978-3-319-17046-6_8|isbn=978-3-319-17045-9}}</ref><ref>{{Cite journal|url=http://www.jstor.org/stable/20022840|title=The Space-Time Manifold of Relativity. The Non-Euclidean Geometry of Mechanics and Electromagnetics|author1=Wilson, Edwin B.|author2=Lewis, Gilbert N.|year=1912|journal=Proceedings of the American Academy of Arts and Sciences|volume=48|issue=11|pages=389–507|doi=10.2307/20022840|jstor=20022840}}</ref>