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Ehrenfest paradox

Ehrenfest paradox proper noun: a relativistic paradox concerning the concept of Born rigidity within special relativity, where an ideally rigid cylinder that is made to rotate about its axis of symmetry. The radius R as seen in the laboratory frame is always perpendicular to its motion and should therefore be equal to its value R₀ when stationary. However, the circumference should appear Lorentz-contracted to a smaller value than at rest. This leads to the contradiction that R = R₀ and R < R₀.

Proper noun

the Ehrenfest paradox

  1. A relativistic paradox concerning the concept of Born rigidity within special relativity, where an ideally rigid cylinder that is made to rotate about its axis of symmetry. The radius R as seen in the laboratory frame is always perpendicular to its motion and should therefore be equal to its value R₀ when stationary. However, the circumference should appear Lorentz-contracted to a smaller value than at rest. This leads to the contradiction that R = R₀ and R < R₀.

Origin of Ehrenfest paradox

Proposed in 1909 by Paul Ehrenfest.

Questions about Ehrenfest paradox

What does Ehrenfest paradox mean?
Ehrenfest paradox means a relativistic paradox concerning the concept of Born rigidity within special relativity, where an ideally rigid cylinder that is made to rotate about its axis of symmetry. The radius R as seen in the laboratory frame is always perpendicular to its motion and should therefore be equal to its value R₀ when stationary. However, the circumference should appear Lorentz-contracted to a smaller value than at rest. This leads to the contradiction that R = R₀ and R < R₀.
What part of speech is Ehrenfest paradox?
Ehrenfest paradox is a proper noun.

Words near Ehrenfest paradox in the dictionary

  1. Ehrenfest
  2. Ehrenfest equation
  3. Ehrenfest equations
  4. Ehrenfest model
  5. Ehrenfest models
  6. Ehrenfest paradox
  7. Ehrenfest theorem
  8. Ehrenfestian
  9. Ehrenreich
  10. Ehrenreichs
  11. Ehrenstein illusion

Source and license

Adapted from Wiktionary: Ehrenfest paradox (page history and authors). Text available under the Creative Commons Attribution-ShareAlike 4.0 license. Word.ws reformatted the entry and added links. Wiktionary data of 2026-09-02.

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