**Planck time** — In physics, the Planck time ( tP ), is the unit of time in the system of natural units known as Planck units. It is the time it would take a photon travelling at the speed of light in a vacuum to cross a distance equal to the Planck length.cite… … Wikipedia

**Planck time** — noun A natural unit of time, equivalent to the time it takes light to traverse one Planck length; it is the smallest duration of time that has physical meaning … Wiktionary

**Planck units** — are units of measurement named after the German physicist Max Planck, who first proposed them in 1899. They are an example of natural units, i.e. units of measurement designed so that certain fundamental physical constants are normalized to 1. In … Wikipedia

**Time from NPL** — Map showing the location of the Anthorn VLF transmitter within Cumbria … Wikipedia

**Time** — This article is about the measurement. For the magazine, see Time (magazine). For other uses, see Time (disambiguation). The flow of sand in an hourglass can be used to keep track of elapsed time. It also concretely represents the present as… … Wikipedia

**Planck epoch** — In physical cosmology, the Planck epoch (or Planck era), named after Max Planck, is the earliest period of time in the history of the universe, from zero to approximately 10 43 seconds (one Planck time), during which quantum effects of gravity… … Wikipedia

**Planck length** — unit of length name=Planck length m=0.00000000000000000000000000000000001616252 accuracy=5 The Planck length, denoted by scriptstyleell P , is the unit of length approximately 1.6 times; 10−35 meters, 6.3 times; 10−34 inches, or about 10−20 times … Wikipedia

**Time zone** — Timezone and TimeZone redirect here. For other uses, see Time zone (disambiguation). Local time redirects here. For the mathematical concept, see Local time (mathematics). This article is about time zones in general. For a list of time zones by… … Wikipedia

**Time signal** — These automatic signal clocks were synchronized by telegraphy in 1905 before the widespread use of radio A time signal is a visible, audible, mechanical, or electronic signal used as a reference to determine the time of day. Contents 1 Audible… … Wikipedia

**Time dilation** — This article is about a concept in physics. For the concept in sociology, see time displacement. In the theory of relativity, time dilation is an observed difference of elapsed time between two events as measured by observers either moving… … Wikipedia