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The Perspectives of Non-Ideal Quantum Reference Frames

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arxiv 2512.19343 v2 pith:3TQB2JNB submitted 2025-12-22 quant-ph gr-qc

The Perspectives of Non-Ideal Quantum Reference Frames

classification quant-ph gr-qc
keywords non-idealperspectivegroupidealperspectivesqrfsquantumreference
verification ladder T0 review T1 audit T2 compute T3 formal T4 reserved
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We define the perspective of any quantum reference frame (QRF) and construct reversible transformations between different perspectives. Our construction is based on two principles motivated operationally by the change from relative to absolute coordinates and leads to an incoherent group averaging approach with general symmetry group. Thereby, it extends the framework of [arXiv:2110.13199] from ideal QRFs, which generally require infinite resources like energy or angular momentum, to non-ideal QRFs, with only finite resources. We find that the perspective of a non-ideal QRF deviates significantly from that of an ideal QRF: Firstly, systems described relative to a non-ideal QRF appear superselected. Secondly, the structure of the perspective of a non-ideal QRF attests that successive relational operations on a system lead to back-reaction on this QRF.

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Cited by 11 Pith papers

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score.

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    quant-ph 2026-07 accept novelty 7.5

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  7. Reduced Quantum-Reference-Frame Channels for Open Quantum Systems

    quant-ph 2026-07 accept novelty 6.0

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    Lattice QED is established as a quantum error-correcting code beyond stabilizers, with explicit recovery operations constructed via quantum reference frames for gauge and fermionic sectors.

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    quant-ph 2026-04 unverdicted novelty 6.0

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  11. Indefinite probabilities in quantum spacetime: A deepening of unpredictability

    quant-ph 2026-05 unverdicted novelty 5.0

    Using the SU_q(2) quantum group for spin rotations yields non-commuting probability operators, implying indefinite probabilities and preventing sharp determination of relative observer orientations.