Encyclopedia Britannica
Encyclopedia Britannica
SUBSCRIBE
SUBSCRIBE
  • Home
  • History & Society
  • Science & Tech
  • Biographies
  • Animals & Nature
  • Geography & Travel
  • Arts & Culture
  • ProCon
  • Money
  • Games & Quizzes
  • Videos
  • On This Day
  • One Good Fact
  • Dictionary
  • New Articles
History & Society
  • Lifestyles & Social Issues
  • Philosophy & Religion
  • Politics, Law & Government
  • World History
Science & Tech
  • Health & Medicine
  • Science
  • Technology
Biographies
  • Browse Biographies
Animals & Nature
  • Birds, Reptiles & Other Vertebrates
  • Bugs, Mollusks & Other Invertebrates
  • Environment
  • Fossils & Geologic Time
  • Mammals
  • Plants
Geography & Travel
  • Geography & Travel
Arts & Culture
  • Entertainment & Pop Culture
  • Literature
  • Sports & Recreation
  • Visual Arts
  • Companions
  • Demystified
  • Image Galleries
  • Lists
  • Podcasts
  • Spotlight
  • Summaries
  • Top Questions
  • #WTFact
  • Britannica Kids
Ask the Chatbot Games & Quizzes History & Society Science & Tech Biographies Animals & Nature Geography & Travel Arts & Culture ProCon Money Videos
Planck length
Directory
References
Discover
Salem Witch Trials. Photogravure after the painting by Walter McEwen titled - The Witches - circa 1890s.
How Rye Bread May Have Caused the Salem Witch Trials
Demystified - Do Lemmings Really Commit Mass Suicide? illustration
Do Lemmings Really Commit Mass Suicide?
Dancers at a Cinco de Mayo festival at the Mission District, San Francisco, California. (Photo dated 2019.) holidays
Is Cinco de Mayo Mexico's Independence Day?
New York NY/ USA- November 23, 2018 Hordes of shoppers throng the Macy's Herald Square flagship store in New York looking for bargains on the day after Thanksgiving, Black Friday.
Why Is It Called Black Friday?
NBA Lakers Celtics Finals Kevin Garnett shooting.
10 Great Sports Rivalries
Close up of praying mantis walking on stone ground against a blurred background in Japan
6 Animals That Eat Their Mates
Statue of Nostradamus
Nostradamus and His Prophecies

Planck length

physics

Learn about this topic in these articles:

cosmology and string theory

  • Examine the observable universe's place within the whole universe
    In cosmology: Superunification and the Planck era

    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 Earth.

    Read More