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Updated: Jun 22, 2025
06:42
Magnetically Induced Rotating Rayleigh-Taylor Instability
Published on: March 3, 2017
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Amplification of electromagnetic fields by a rotating body
M C Braidotti1, A Vinante2, M Cromb3
1School of Physics and Astronomy, University of Glasgow, G12 8QQ, Glasgow, UK.
Nature Communications
|June 27, 2024
Summary
Scientists demonstrate electromagnetic wave amplification by a spinning cylinder, confirming a 1971 prediction. This breakthrough validates the Zel
Area of Science:
- Physics
- Electromagnetism
- Condensed Matter Physics
Background:
- The Zel'dovich mechanism predicted electromagnetic (EM) wave amplification by a rotating metallic cylinder.
- This effect was considered unobservable due to the high rotation speed requirement, exceeding radiation frequency.
Purpose of the Study:
- To experimentally measure the amplification of EM waves scattered by a rotating metallic cylinder.
- To validate the Zel'dovich mechanism and explore its connection to induction generators.
Main Methods:
- An aluminum cylinder was spun within the gap of a toroid LC-circuit.
- The amplification of EM fields generated by the circuit and scattered by the cylinder was measured.
Main Results:
- Negative induced resistance was observed when the Zel'dovich condition (cylinder rotation speed > radiation frequency) was met.
- This negative resistance confirmed the amplification of incoming EM fields.
Conclusions:
- The experiment successfully demonstrated and measured the Zel'dovich mechanism for EM wave amplification.
- Results link induction generator principles to this fundamental physics effect, opening avenues for quantum regime studies and quantum friction research.
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