Williams H.T. Discrete Quantum Mechanics

Morgan & Claypool Publishers, 2015. — 138 p. — ISBN 978-1-6817-4061-4.Most of us are best at understanding and believing things that align with our experience. We – at least most of ‘we’ – have nonetheless proven capable of buying into propositions that defy everyday experience, common sense. There are few who nowadays do not believe the surface of the earth is curved, even though no-one reports a sensation that the ground is constantly moving under his or her feet and few have watched a ship slowly dip below the horizon as it sails into the distance. Within a paltry handful of centuries since it was proposed, the notion of the earth as bumpy ball has become commonplace.
Quantum mechanics, just out of its first century, has not received such uniform acceptance. Some are barely aware of what it is (despite living surrounded by quantum-enabled devices), others know a bit about it (e.g. can use the phrase ‘uncertainty principle’ in a complete sentence) and a tiny few have studied it and can make use of it. If Richard Feynman is correct, however, nobody understands it. To the general public, a cat both dead and alive and instantaneous teleportation are interesting bits of fantasy rather than things made possible by the reality of quantum behaviorPreface
Postulates
Two-state systems
Entanglement
Quantum angular momentum
Quantum many-body problem
Infinity, and beyond
Appendix A Relevant results from linear algebra
Appendix B Directory of definitions and notation