Plank Time?

Has anyone heard of Plank Time? I read something about it in National Geographic, and i think it has something to due with the time it takes for the laws of physics to be applied to matter. I believe the time is some where in the 43rd decimal place. Anyone ever heard of this?

Plank Time? You must be thinking of the Logopolitans.

Thank you. I’ll be here all week.

http://zebu.uoregon.edu/~js/glossary/planck_time.html

"Planck Time :
The characteristic linear dimension is given as a certain combination of the three most fundamental constants of nature: (1) Planck’s constant h (named after the German physicist Max Planck, the founder of quantum physics), (2) the speed of light c, and (3) the universal gravitational constant G. The combination, called the Planck length (Gh/c3)1/2, equals roughly 10-33 cm, far smaller than the distances to which elementary particles can be probed in particle accelerators on the Earth.

The energies needed to smash particles to within a Planck length of each other were available to the universe at a time equal to the Planck length divided by the speed of light. This time, called the Planck time (Gh/c5)1/2, equals approximately 10-43 second. At the Planck time, the mass density of the universe is thought to approach the Planck density, c/hG, roughly 1093 g/cc . Contained within a Planck volume is a Planck mass (hc/G)1/2, roughly 10-5 g. An object of such mass would be a quantum black hole, with an event horizon close to both its own Compton length (distance over which a particle is quantum mechanically “fuzzy”) and the size of the cosmic horizon at the Planck time. Under such extreme conditions, spacetime cannot be treated as a classical continuum and must be given a quantum interpretation."

etc etc

Strictly speaking, Planck Time is the amount of time it takes for a photon travelling at the speed of light to travel one Planck length, about 10[sup]-43[/sup] seconds. It is the shortest unit of time that has any meaning.

You might be thinking of the Planck Era which is also referred to as Planck Time. It is the point in the history of the Universe after which rapid expansion occured and in which our current theories of quantum mechanics and general relativity apply. Before that, the universe was so small that quantum effects were very important. We can’t describe the behavior of the universe during this period with relativity alone. Physicists are working to describe this period by unifying quantum mechanics and general relativity into a theory of quantum gravity. When they do, we’ll know whether or not the Universe had a beginning.

There’s LOTS of information on the web about Cosmology, quantum gravity, and all things Planck. The web was invented to facilitate information exchange between physicists.