Spacetime

Time is the continuous progression of existence that occurs in an apparently irreversible succession from the past, through the present, and into the future. Time dictates all forms of action, age, and causality, being 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 conscious experience. Time is often referred to as a fourth dimension, along with three spatial dimensions.

thumb|right|A right-handed three-dimensional Cartesian coordinate system used to indicate positions in space|class=skin-invert-image

In physics, spacetime, also called the space-time continuum, is a mathematical model that fuses the three dimensions of space and the one dimension of time into a single four-dimensional continuum. Spacetime diagrams are useful in visualizing and understanding relativistic effects, such as how different observers perceive where and when events occur.

space-time coordinate transformation that conserves the form of Maxwell’s equations

mathematical model used in general relativity

concept that there might be more than one dimension of time

In philosophy, four-dimensionalism (sometimes called the doctrine of temporal parts) is a family of views about the ontology of time and persistence. Roughly, four-dimensionalists hold that persisting objects are extended in time in a way analogous to their extension in space, and that they are composed of distinct temporal parts located at different times, in addition to their spatial parts.

term

mathematical transformation in physics that moves the times of events through a common interval

Metric in relativity

particular set of coordinates for the Schwarzschild metric

Non-simultaneity or nonsynchronism (German: Ungleichzeitigkeit, sometimes also translated as non-synchronicity) is a concept in the writings of Ernst Bloch which denotes the time lag, or uneven temporal development, produced in the social sphere by the processes of capitalist modernization and/or the incomplete nature of those processes. The term, especially in the phrase "the simultaneity of the non-simultaneous", has been used subsequently in predominantly Marxist theories of modernity, world-systems, postmodernity and globalization.

Lorentzian metric describing an isotropic, expanding, nonhomogenous universe