25 April 2009

Einstein Was Never in Dorothy’s Unique Position

In 1921, J. Malcolm Bird, an editor at Scientific American, compiled a book titled Einstein's Theories of Relativity and Gravitation: A Selection of Material from the Essays Submitted in the Competition for the Eugene Higgins Prize of $5,000.

The chapter “The General Theory: Fragments of Particular Merit on this Phase of the Subject” starts with this passage by Norman E. Gilbert, professor of physics at Dartmouth College:

When Dorothy was carried by the cyclone from her home in Kansas to the land of Oz, together with her uncle's house and her little dog Toto, she neglected to lower the trap door over the hole in the floor which formerly led to the cyclone cellar and Toto stepped through. Dorothy rushed to the opening expecting to see him dashed onto the rocks below but found him floating just below the floor. She drew him back into the room and closed the trap.

The author of the chronicle of Dorothy's adventures explains that the same force which held up the house held up Toto, but this explanation is not necessary. Dorothy was now floating through space and house and dog were subject to the same forces of gravitation which gave them identical motions. Dorothy must have pushed the dog down onto the floor and in doing so must herself have floated to the ceiling whence she might have pushed herself back to the floor. In fact gravitation was apparently suspended and Dorothy was in a position to have tried certain experiments which Einstein has never tried because he was never in Dorothy's unique position.
A poster of W. W. Denslow’s illustration of this moment in The Wonderful Wizard of Oz is available as a poster from AllPosters.com.

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