Quantum reference frame transformations as symmetries and the paradox of the third particle

  title={Quantum reference frame transformations as symmetries and the paradox of the third particle},
  author={Marius Krumm and Philipp A. Hoehn and Markus P. Mueller},
In a quantum world, reference frames are ultimately quantum systems too – but what does it mean to "jump into the perspective of a quantum particle"? In this work, we show that quantum reference frame (QRF) transformations appear naturally as symmetries of simple physical systems. This allows us to rederive and generalize known QRF transformations within an alternative, operationally transparent framework, and to shed new light on their structure and interpretation. We give an explicit… 

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