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Time is an observed phenomenon, by means of which human beings sense and record changes in the environment and in the universe. A literal definition is elusive. Time has been called an illusion, a dimension, a smooth-flowing continuum, and an expression of separation among events that occur in the same physical location.

Time is a practical convenience in modern life. Numerous standards have been set up, allowing people to coordinate events and, in general, keep their lives running smoothly. The earth has been divided into so-called time zones that reflect the fact that high noon occurs at different times at different places on the planet. All of these time zones are referenced to the time at the longitude of Greenwich, England. A universal standard, coinciding almost exactly with the time at Greenwich, is known as Coordinated Universal Time (UTC). There are various other time standards.

The fundamental unit of time in the International System of Units (SI) is the second (symbolized s or sec). One second elapses during the occurrence of exactly 9,192,631,770 (9.192631770 x 109) cycles of the radiation produced by the transition between two levels of the cesium 133 atom. Other common units of time include the hour, the mean solar day, and the synodic year (sun-based earth year). The table below shows the relationship among the second, the hour, the mean solar day, and the synodic year.

(and symbol)
To convert time in given unit
to time in seconds, multiply by:
To convert time in seconds
to time in given unit, multiply by:
hour (hr) 3600 2.7778 x 10-4
mean solar day (dy) 8.6400 x 104 1.1574 x 10-5
synodic year (yr) 3.1558 x 107 3.1688 x 10-8

Isaac Newton believed that time is continuous, and that it flows at an unchanging rate everywhere in the universe. This was accepted by most scientists until the Michelson-Morley experiment around the end of the 19th century, from which it was discovered that the speed of light is the same regardless of the direction of propagation, and regardless of the motion of the source. Albert Einstein considered this result an axiom, from which he derived the special and general theories of relativity. According to relativistic physics, the rate at which time passes depends on the relative motion between observers, and also on the strength of a gravitational or acceleration field.

Time is one of three primary phenomena in the meter/kilogram/second (mks) and centimeter/gram/second (cgs) systems of measurement. It is one of seven fundamental quantities or phenomena in the International System of Units.

Also see mks system of units, cgs system of units or small-unit metric system, the International System of Units (SI), and our Table of Physical Units.

This was last updated in October 2006

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Time is a field. It IS space. Space as we see it is not empty. It is made up entirely of massless photons. the universe is moving through this sea of photons called time at a set rate determined by the big bang. We can also move through time soup individually upon a common surface like everyone else on the planet. Time is the unified field. Energy moves through time as a wave or vibration. Our auras are energy that precedes us as we move through the sea of photons called time. As we move through the airy sea of ever present photons called time, our auras bubble ahead of us and show us farther into the field of time to see what is coming and we can avoid collision. The field immediately closes behind you as you pass through time. The photons your aura touches as you pass through the time medium, bond into a solid mass capturing your stream of consciousness you leave in your wake. This is your past and you cannot change it. It is always connected to you as you move through time. "You cannot escape your past" You can send a probe from your brain down the stream of consciousness to retrieve memories but they are encased in a solid and cannot be changed. Whenever your conscience moves it always moves through time leaving a stream of consciousness memories/past in its wake. The photons contacting this stream of your consciousness solidify encasing your memories in an un penetrable solid. The photons around it also solidify so when you go back to access that memory you can probe around the memory area from your memory stream and see what it was like that day and remember the surroundings of the event Everything in that moment of time solidifies around it....So you cannot go back through that time space ever again it is now a solid. Memory lane is solid and unchangeable. This is why you cannot travel backward in time. Its a solid and you cannot move through it. Time is no longer viscous and penetrable. Imagine a thin highly viscous jello made of invisible massless spheres in every space. This medium is called time. This medium will become the catalyst of everything. Waves and moving particles are specific energies using the photons as a carrier medium for all things possible. The faster we move through space the farther the bubble of or aura or consciousness moves ahead of us to see what is coming. if we can see clearly the things that far ahead in time it is like seeing into the future. Moving faster than the photon connectivity rate of C, would render you sightless, since you are moving faster that the light rays allowing you to see. So travel to the future is impossible but viewing it is not.
For me where all talk about time ends :
T=E x D.....
Time=existence x Duration...
I know ...duration is a part
It ? Is?
Talking and tinking about time is forgetting
being a timely being yourself..

Cheers !
I tend to stop sat T = C - D Time = Comedy - Tragedy or the better known expression, 'Tragedy plus time equals comedy'. Proofs have never been systematically reviewed, but compelling nonetheless.
time is useless to us , don't really need it.
ewan ko ???
A good defination about time. Love it. !


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