# The apparent shape of a relativistically moving sphere

@article{Penrose1959TheAS, title={The apparent shape of a relativistically moving sphere}, author={Roger Penrose}, journal={Mathematical Proceedings of the Cambridge Philosophical Society}, year={1959}, volume={55}, pages={137 - 139} }

It would be natural to assume that, according to the special theory of relativity, an object moving with a speed comparable with that of light should appear to be flattened in the direction of motion on account of its FitzGerald-Lorentz contraction. It will be shown here, however, that this is by no means generally the case. It turns out, in particular, that the appearance of a sphere, no matter how it is moving, is always such as to present a circular outline to any observer. Thus an…

## 209 Citations

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