English

Random coding exponents galore via decoupling

Quantum Physics 2015-09-30 v5 Information Theory math.IT

Abstract

A missing piece in quantum information theory, with very few exceptions, has been to provide the random coding exponents for quantum information-processing protocols. We remedy the situation by providing these exponents for a variety of protocols including those at the top of the family tree of protocols. Our line of attack is to provide an exponential bound on the decoupling error for a restricted class of completely positive maps where a key term in the exponent is in terms of a R\'enyi \alpha-information-theoretic quantity for any \alpha \in (1,2]. Among the protocols covered are fully quantum Slepian-Wolf, quantum state merging, quantum state redistribution, quantum/classical communication across channels with side information at the transmitter with or without entanglement assistance, and quantum communication across broadcast channels.

Keywords

Cite

@article{arxiv.1504.07075,
  title  = {Random coding exponents galore via decoupling},
  author = {Naresh Sharma},
  journal= {arXiv preprint arXiv:1504.07075},
  year   = {2015}
}

Comments

The changes are confined to Sec. 10. Added an exponentially decaying term to (152) ((149) in previous version) to make it precise - this makes the trace of one state to be one, this adds 1 more error term and 3 more equations, made the multiplying factor in the errors to be 20, and in few places the system labels were 'F' instead of 'G'

R2 v1 2026-06-22T09:23:22.281Z