By measuring the amount of static acceleration due to gravity, the chip knows the angle a device is being tilted at with respect to the earth.

BBC: NEWS | Technology | Motion-sensitive laptop developed

No amount of argument will change the law of gravity as I slip off of a roof.

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The fastest thing in the universe is light, and the amount of time it takes a photon (in a vacuum, absent of gravity), to transit a planck is called planck-time.

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