Dynamical time scale has two distinct meanings and usages, both related to astronomy:
- 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.
- 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 Scale: Stellar Physics, Time Standards
Famous quotes containing the words time and/or scale:
“I’ve seen things you people wouldn’t believe. Attack ships on fire off the shoulder of Orion. I watched seabeams glitter in the dark near the Tennhauser Gate. All those moments will be lost in time like tears in rain. Time to die.”
—David Webb Peoples, U.S. screenwriter, and Ridley Scott. Roy Batty, Blade Runner, final words before dying—as an android he had a built-in life span that expired (1982)
“There is something in us, somehow, that, in the most degraded condition, we snatch at a chance to deceive ourselves into a fancied superiority to others, whom we suppose lower in the scale than ourselves.”
—Herman Melville (1819–1891)