Difference between revisions of "Quantum Information Theory"

Revision as of 20:19, 16 December 2022

Full Title or Meme

Quantum Information Theory (QIS) is a further abstraction of an abstract model of real-world physics.

Context

• QIS was first suggested by Richard Feynman as a means to model the real quantum work of subatomic interactions in Information Theory.

Reversibility

• The current model of physical reality (some call the model a set of laws) shows no preference between moving forward versus backwards in time. Particles' "motions" can be predicted either way.
• What is most interesting is that Landauer's principle was originally developed in 1961 to predict the lower theoretical limit of energy consumption of computation. It holds that "any logically irreversible manipulation of information, such as the erasure of a bit or the merging of two computation paths, must be accompanied by a corresponding entropy increase in non-information-bearing degrees of freedom of the information-processing apparatus or its environment".^[1] So, A reversable computation is one in which no information is erased and, in principle, may be carried out without releasing any heat.
• In 2022 we could say the same about quantum processes.^[2] In particular quantum error codes are very efficient at encoding information which comes from the fact that "quantum mechanics is reversible, and thus information must be preserved somewhere." This leads to description of how information that falls into a black hole is theoretically recoverable.
• Current efforts to reduce

Three Areas of QIS

These areas were taken from Hoofnagle and Garfinkel's book^[3]

Quantum Sensing

Quantum Communication

See the wiki page on the Quantum Computing Threat to existing cryptography.

Quantum Computing

• Most closely tracks the original suggest from Richard Feynman in modeling the physical reality of Quantum Mechanics.
• Note that some would place the Quantum Computing Threat in this category as well. Any taxonomy such as this runs into classification ambiguity.

References

1. ↑ Charles H. Bennett, Notes on Landauer's principle, Reversible Computation and Maxwell's Demon. Studies in History and Philosophy of Modern Physics volume=34 issue=3 pp. 501–510 (2003) http://www.cs.princeton.edu/courses/archive/fall06/cos576/papers/bennett03.pdf DOI 10.1016/S1355-2198(03)00039-X
2. ↑ Don, Monroe, Quantum Computers and the Universe CACM 65 No 12, (2022-12)
3. ↑ Chris Jay Hoofnagle and Simson L. Garfinkel, Law and Policy for the Quantum Age Cambridge UP 2022 ISN 9781108793179

Other Material

• See the wiki page on Second Law of Thermodynamics

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