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arXiv · 0711.4767

Observation of negative-frequency waves in a water tank: A classical analogue to the Hawking effect?

Germain Rousseaux·Christian Mathis·Philippe Maissa·Thomas G. Philbin·Ulf Leonhardt
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Abstract

The conversion of positive-frequency waves into negative-frequency waves at the event horizon is the mechanism at the heart of the Hawking radiation of black holes. In black-hole analogues, horizons are formed for waves propagating in a medium against the current when and where the flow exceeds the wave velocity. We report on the first direct observation of negative-frequency waves converted from positive-frequency waves in a moving medium. The measured degree of mode conversion is significantly higher than expected from theory.

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Germain Rousseaux, Christian Mathis, Philippe Maissa, Thomas G. Philbin, Ulf Leonhardt. 2008-03-01. Observation of negative-frequency waves in a water tank: A classical analogue to the Hawking effect?. https://doi.org/10.1088/1367-2630%2F10%2F5%2F053015

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