# Classical aspects of lightlike dimensional reduction

@article{Minguzzi2006ClassicalAO, title={Classical aspects of lightlike dimensional reduction}, author={Ettore Minguzzi}, journal={Classical and Quantum Gravity}, year={2006}, volume={23}, pages={7085 - 7110} }

Some aspects of lightlike dimensional reduction in flat spacetime are studied with emphasis to classical applications. Among them the Galilean transformation of shadows induced by inertial frame changes is studied in detail by proving that (i) the shadow of an object has the same shape in every orthogonal-to-light screen, (ii) if two shadows are simultaneous in an orthogonal-to-light screen then they are simultaneous in any such screen. In particular, the Galilean group in 2 + 1 dimensions is…

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