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Planck length

File:Triangle_of_everything_simplified_2_triangle_of_everything_-_Planck_Units.png · Wikimedia Commons · See Wikimedia Commons

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Planck length

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very small-scale unit of length

AI overview

The Planck length is the smallest meaningful unit of distance in physics, calculated from fundamental constants to be about 1.6 × 10⁻³⁵ meters—far smaller than anything we can currently observe or measure. It matters because it represents a theoretical limit where our current understanding of physics breaks down and quantum effects of gravity become dominant, making it important for developing theories that unite quantum mechanics with general relativity.

AI-generated from the Wikipedia summary — may contain errors.

Wikidata facts

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Derived Planck Units 2017 by Pi number.jpg
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numeric value
0.00000000000000000000000000000000001616255
conversion to SI unit
0.00000000000000000000000000000000001616255
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Article

A mass–radius log plot of various objects

In particle physics and physical cosmology, Planck units are a system of units of measurement defined exclusively in terms of four universal physical constants: c, G, ħ, and kB. Expressing one of these physical constants in terms of Planck units yields a numerical value of 1. They are a system of natural units, defined using fundamental properties of nature (specifically, properties of free space) rather than properties of a chosen prototype object. Originally proposed in 1899 by German physicist Max Planck, they are relevant in research on unified theories such as quantum gravity.

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