Tidslignende

Tidslignende, which translates to "time-like" in English, is a concept primarily found in theoretical physics, particularly within the framework of general relativity and spacetime geometry. It describes a path or trajectory through spacetime that is always directed towards the future. More formally, a time-like curve is a path where the proper time interval between any two points on the path is positive. This means that an observer traveling along a time-like path would always experience the passage of time in a consistent, forward direction. In contrast, space-like paths have a negative proper time interval, implying that two events on such a path could be simultaneous for some observers and that no causal connection exists between them. Light-like or null paths are those where the proper time interval is zero, representing the paths taken by photons. The distinction between time-like, space-like, and light-like intervals is fundamental to understanding causality and the structure of spacetime as described by Einstein's theory of relativity. Events that can be causally connected by signals traveling at or below the speed of light are said to lie within each other's light cones, with time-like paths representing the possible worldlines of massive objects moving through spacetime.