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arXiv · 1406.0634

Relativistic elasticity of rigid rods and strings

Jose Natario
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Abstract

We show that the equation of motion for a rigid one-dimensional elastic body (i.e. a rod or string whose speed of sound is equal to the speed of light) in a two-dimensional spacetime is simply the wave equation. We then solve this equation in a few simple examples: a rigid rod colliding with an unmovable wall, a rigid rod being pushed by a constant force, a rigid string whose endpoints are simultaneously set in motion (seen as a special case of Bell's spaceships paradox), and a radial rigid string that has partially crossed the event horizon of a Schwarzschild black hole while still being held from the outside.

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Jose Natario. 2014-06-03. Relativistic elasticity of rigid rods and strings. https://doi.org/10.1007/s10714-014-1816-x

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