Quantum Reference Frames, Revisited

The topic of quantum reference frames (QRFs) has attracted a great deal of attention in the recent literature. Potentially, the correct description of such frames is important for both the technological applications of quantum mechanics and for its foundations, including the search for a future theory of quantum gravity.

In this letter, we point out potential inconsistencies in the mainstream approach to this subject and propose an alternative definition that avoids these problems. Crucially, we reject the notion that transformations between QRFs can be represented by unitary operators and explain the clear physical reasons for this. An experimental protocol, capable of empirically distinguishing between competing definitions of the term, is also proposed. The implications of the new model, for uncertainty relations, spacetime symmetries, gauge symmetries, the quantization of gravity, and other foundational issues are discussed, and possible directions for future work in this field are considered.

I obtained my PhD in cosmology from Queen Mary, University of London, before taking up a postdoctoral fellowship at the Research Center for the Early Universe in the University of Tokyo. After working in Japan, I became a Lecturer in theoretical physics at the Institute for Fundamental Study in Naresuan University, Thailand, and held a Visiting Researcher position at Nanyang Technological University, Singapore, before joining the School of Physics at Sun Yat-Sen University, China, as an Associate Professor. Since the covid-19 pandemic, I have held positions as a Visiting Scientist at the Frankfurt Institute for Advanced Studies and as a Researcher at the National Astronomical Research Institute of Thailand and the Research Center for Quantum Technology in Chiang Mai University. I am currently an Associate Faculty member of Babes-Bolyai University in Cluj-Napoca, Romania. My research interests include cosmology and astrophysics, high-energy particle physics, quantum field theory, quantum information theory and quantum foundations, and phenomenological quantum gravity. I have a special interest in the connection between Generalized Uncertainty Relations and dark energy and my recent work focuses on the possible connections between quantum geometry, GURs, and quantum reference frames.