Time scale

A time scale specifies divisions of time.

• Time standard, a specification of either the rate at which time passes, or points in time, or both
• Reference to an approximate duration or quantity of time:
  • Orders of magnitude (time) as a power of 10 in seconds;
  • as a reference of time unit

• Geological time scale, a scale that divides up the history of Earth into scientifically meaningful periods

In astronomy and astrophysics

• Dynamical time scale either (in stellar physics), measures the length of time over which changes in one part of a body can be communicated to the rest of that body, or (in celestial mechanics) is a realization of a time-like argument based on a dynamical theory
• Nuclear timescale, estimates the lifetime of a star based solely on its rate of fuel consumption
• Thermal time scale, estimates the lifetime of a star once its fuel reserves at its center are used up or if they were to disappear

In cosmology and particle physics

• Planck time, the time scale beneath which quantum effects are comparable in significance to gravitational effects

In mathematics

• Time-scale calculus, the unification of the theory of difference equations with differential equations

In music

• rhythm, a temporal pattern of events
• Time scale (music), divides up music into sections based on the scope