The Viterbi Algorithm and Quantum Communications

eldavojohn writes "There have been a lot of tests in using quantum mechanics to communicate across large distances. But a student & a professor at USC have proven that the Viterbi algorithm can be applied to quantum communication. In the traditional Alice sends Bob a message scenario, 'Bob can reliably spot errors, and knows which message qubits are bogus before he opens the message — crucial, because opening it destroys it; and if it is garbled, he has nothing.'"

Comments

This is for deriving information from Markov sets

[Sir_Real]

For those wondering what use this has.

Say you had.... a buttload of code, and wanted to find the context free grammar for the language. You could use a Viterbi algorithm to pull out a statistically likely parse tree (the Viterbi Parse). The thing you're pulling from is often called a Markov process which is a model for the evolution of a state changing, memoryless system. So, over time, you can retrieve a grammar from a running process.

How this applies to QM is left as an exercise to the reader (5 stars, unless you're Don K His-self, in which case it's 2).

ianaqp

Get the full Ph.D. thesis here:

[Falkkin]

TFA is a bit short on details, as expected for a general-audience press release. In particular, they throw the word "Viterbi" out there without ever explaining what the heck it means; probably an artifact of USC containing the *Viterbi* School of Engineering. The juicy technical bits can be found in his thesis here:

Title: Quantum Coding with Entanglement
Authors: Mark M. Wilde
Thesis PDF ... and for a basic overview of the underlying concepts, of course the Wikipedia page on the Viterbi algorithm is helpful.