The Planck Length: The Smallest Length At Which Space-Time Functions
The Planck length is the theoretical length at which the laws of space-time begin to unravel. It's orders of magnitude smaller than a proton, and unable to be physically measured by any equipment available today. It's defined by three constants: the gravitational constant, the speed of light in a vacuum, and Planck's constant, a value used in quantum mechanics.
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Key Facts In This Video
The Planck length is approximately 1.6 x 10^-35 meters. (1:08)
The Planck length is calculated using three constants: Planck's constant, the gravitational constant, and the speed of light. (2:41)
Space itself is not properly defined on length scales smaller than the Planck length. (4:57)