Approximating relational observables by absolute quantities: a quantum accuracy-size trade-off

TY - JOUR

T1 - Approximating relational observables by absolute quantities

T2 - a quantum accuracy-size trade-off

AU - Busch, Paul

AU - Loveridge, Leon Deryck

AU - Miyadera, Takayuki

N1 - © 2016 IOP Publishing Ltd. This is an author-produced version of a paper accepted for publication. Uploaded with permission of the publisher/copyright holder. Further copying may not be permitted; contact the publisher for details

PY - 2016/3/22

Y1 - 2016/3/22

N2 - The notion that any physical quantity is defined and measured relative to a reference frame is traditionally not explicitly reflected in the theoretical description of physical experiments where, instead, the relevant observables are typically represented as 'absolute' quantities. However, the emergence of the resource theory of quantum reference frames as a new branch of quantum information science in recent years has highlighted the need to identify the physical conditions under which a quantum system can serve as a good reference. Here we investigate the conditions under which, in quantum theory, an account in terms of absolute quantities can provide a good approximation of relative quantities. We find that this requires the reference system to be large in a suitable sense.

AB - The notion that any physical quantity is defined and measured relative to a reference frame is traditionally not explicitly reflected in the theoretical description of physical experiments where, instead, the relevant observables are typically represented as 'absolute' quantities. However, the emergence of the resource theory of quantum reference frames as a new branch of quantum information science in recent years has highlighted the need to identify the physical conditions under which a quantum system can serve as a good reference. Here we investigate the conditions under which, in quantum theory, an account in terms of absolute quantities can provide a good approximation of relative quantities. We find that this requires the reference system to be large in a suitable sense.

KW - quantum mechanics

KW - quantum reference frame

UR - https://arxiv.org/abs/1510.02063

U2 - 10.1088/1751-8113/49/18/185301

DO - 10.1088/1751-8113/49/18/185301

M3 - Article

SN - 1751-8113

VL - 49

JO - Journal of Physics A: Mathematical and Theoretical

JF - Journal of Physics A: Mathematical and Theoretical

IS - 18

M1 - 185301

ER -