Dynamical Time Scale

Dynamical time scale has two distinct meanings and usages, both related to astronomy:

  1. In one use, which occurs in stellar physics, the dynamical time scale is alternatively known as the freefall time scale, and is in general, the length of time over which changes in one part of a body can be communicated to the rest of that body. This is often related to the time taken for a system to move from one equilibrium state to another after a sudden change.
  2. In another use, in connection with time standards, dynamical time is the time-like argument of a dynamical theory; and a dynamical time scale in this sense is the realization of a time-like argument based on a dynamical theory: that is, the time and time scale are defined implicitly, inferred from the observed position of an astronomical object via a theory of its motion. A first application of this concept of dynamical time was the definition of the ephemeris time scale (ET).

Read more about Dynamical Time ScaleStellar Physics, Time Standards

Other articles related to "time, times, dynamical time scale, time scales, time scale":

Weighted Mean - Decreasing Strength of Interactions
... Consider the time series of an independent variable and a dependent variable, with observations sampled at discrete times ... In many common situations, the value of at time depends not only on but also on its past values ... the strength of this dependence decreases as the separation of observations in time increases ...
Dynamical Time Scale - Time Standards
... the length of the day) was both irregular on short time scales, and was slowing down on longer time scales ... their gravitational ephemerides would be a better way to determine a uniform time scale ... was published in 1948 and adopted by the IAU in 1952 (see Ephemeris time - history) ...
Alfred Korzybski - Early Life and Career
... Korzybski was born in Warsaw, Poland which at that time was part of the Russian Empire ... a new theory of humankind mankind as a "time-binding" class of life (humans perform time binding by the transmission of knowledge and abstractions through ...
Unix Time
... Unix time, or POSIX time, is a system for describing instances in time, defined as the number of seconds that have elapsed since midnight Coordinated ... It is neither a linear representation of time nor a true representation of UTC ... Unix time may be checked on some Unix systems by typing date +%s on the command line ...
Theoretical Astronomy - Theory of Astronomical Time Keeping - Stellar Dynamical Time Scale
... For a star, the dynamical time scale is defined as the time that would be taken for a test particle released at the surface to fall under the star's potential to the centre ... In other words, the dynamical time scale measures the amount of time it would take a certain star to collapse in the absence of any internal pressure ... As an example, the Sun dynamical time scale is approximately 1133 seconds ...

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