|
|
Article: Planck Time
- Article from:
- Encyclopedia of Science and Religion
- Author:
CopyrightCOPYRIGHT 2003 The Gale Group Inc. This material is published under license from the publisher through the Gale Group, Farmington Hills, Michigan. All inquiries regarding rights should be directed to the Gale Group. (Hide copyright information)
|
Planck Time
The Planck time is a unit of time that is defined by three of the fundamental constants of nature: Isaac Newton's constant of gravitation,
G
; the velocity of light in vacuum,
c
; and Max Planck's constant,
h.
These constants may be combined in one and only one way to give a quantity that has the dimensions of a time:
t
planck
= (
Gh/c
5)1/2 = 1.3
×
10-43
s
This unit of time exists independently of all human standards of time measurement. It is defined by the gravitational, relativistic, and quantum aspects of the universe. The universe can be said to be "old" in the well defined sense that it is about 1060 Planck times in age (about thirteen billion years). The ...