English

On quantum subsystem measurement

Quantum Physics 2013-02-12 v1

Abstract

It is assumed that an arbitrary composite bipartite pure state in which the two subsystems are entangled is given, and it is investigated how the entanglement transmits the influence of measurement on only one of the subsystems to the state of the opposite subsystem. It is shown that any exact subsystem measurement has the same influence as ideal measurement on the opposite subsystem. In particular, the distant effect of subsystem measurement of a twin observable, i. e., so-called 'distant measurement', is always ideal measurement on the distant subsystem no matter how intricate the direct exact measurement on the opposite subsystem is.

Keywords

Cite

@article{arxiv.1302.2250,
  title  = {On quantum subsystem measurement},
  author = {Fedor Herbut},
  journal= {arXiv preprint arXiv:1302.2250},
  year   = {2013}
}

Comments

12 pages

R2 v1 2026-06-21T23:23:39.520Z