Speakur

Word Pronunciation & Dictionary

ehrenfest paradox

Word Rarity Very rare

Frequency: Zipf frequency 1.31 in modern English

Syllables
ehren-fest -para-dox
IPA
32
Scrabble Score
16
Letters
4
Syllables
12
Unique Chars

Meaning

name

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.

Etymology

Proposed in 1909 by Paul Ehrenfest.

Inflected Forms

the Ehrenfest paradox (canonical)

Questions

What does ehrenfest paradox mean?
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.
Where does ehrenfest paradox come from?
Proposed in 1909 by Paul Ehrenfest.

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