This module you learned of a new concept in quantum information: entanglement. And what a concept! If you feel like you still don’t grasp all the subtleties behind entanglement, don’t worry: I don’t either. This is the beauty of quantum cryptography, we’re going to get to learn entanglement, not by letting it confound us, but by taking the lead and using entanglement to devise secure cryptosystems!

If you want to learn more about the basics, in particular purifications, Uhlman’s theorem and the Schmidt decomposition, we recommend that you carefully go through the lecture notes. In addition the book by Nielsen and Chuang contains lots of details and examples that you may want to work through.

The quantum secret sharing scheme we saw is discussed here. If you’re interested in reading more on the topic, check out the paper by Cleve, Gottesman and Lo on “How to share a quantum secret“.

Monogamy of entanglement is a very subtle concept. You can read a fun, somewhat historical introduction by Terhal here. The discussion of the three-player CHSH game is based on a paper by Toner, “Monogamy of nonlocal quantum correlations“.