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報導來源：

https://reurl.cc/bYxAdv



利用這種現象，旋轉中的物體可以在一定限制下突破時空限制，而該旋轉則被稱為[黃金
迴旋]。

https://www.youtube.com/watch?v=iEH2infTeH0



原理：

A similar ‘rotational Doppler’ frequency shift happens for twisted waves
and relative rotation.

In the Zel’dovich effect, the metal cylinder needs to rotate fast enough
that from its perspective it ‘sees’ a ‘twisted wave’ shift in angular
frequency, so much that it actually goes to a negative frequency. This
changes the way the wave interacts with the cylinder. Usually the metal would
absorb the wave, but when the wave frequency ‘goes negative’ the wave is in
fact amplified – reflecting off the cylinder with more energy than when it
approached.

“The condition for amplification is from the rotating perspective of the
object,” explains Marion Cromb. “Twisting electromagnetic fields hitting it
have become rotationally Doppler shifted, so much (or so low) that they’ve
gone through zero and into a ‘negative’ angular frequency. Negative
frequency then means negative absorption, and this means amplification.”






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※ 作者: STAV72 2024-09-27 20:06:17
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