However, there is also currently a lot of hype and many unrealistic expectations. The aim of this course is to show you where all the excitment derives from, rigorously and in detail; and to innoculate you against the over-hype.

]]>- Lecture 1, Computation and Complexity video and lecture notes
- Lecture 2: Complexity in Physics video and lecture notes
- Lecture 3: Computability in Physics video and lecture notes

The aim of this course is to select one or two advanced topics in quantum information theory, close to the cutting edge of research, and cover them in some depth and rigour.

This time around, I will focus on quantum information in many-body systems. What do these two topics have to do with each other? Quantum computation aims to engineer complex many-body systems to process information in ways that would not be possible classically. Many-body physics aims to understand the complex behaviour of naturally-occurring many-body systems. In a sense, they are two sides of the same coin. Quantum information theory is now used both to prove important results in many-body physics, and to construct many-body models that exhibit very unusual physics, providing counterexamples to long-standing beliefs in condensed matter theory. This is now one of the fastest-developing areas of the field.

]]>- Lectures 1-2: Computation and Complexity
- Lecture 3: Local Hamiltonians
- Lectures 3-4: Kitaev's Theorem
- Lecture 4: Local clock construction

The slides are courtesy of David. The lecture notes are my handwritten notes from the whiteboard section of David's lectures. All content by David; all mistakes by me!

- MPS motivation (slides)
- MPS lecture notes (handwritten)
- PEPS and topological order (slides)

(The slides are copyright © 2016 David Perez-Garcia, with all rights reserved. The handwritten notes are copyright © 2016 Toby Cubitt, and are licensed under the Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.)

Much of the material covered here (and more!) was originally proven in the Mother of All Protocols paper by Abeyesinghe, Devetak, Hayden and Winter.

These notes largely follow Section 10.9 of Preskill's wonderful lecture notes, with a (very) few modifications and additions.

- Section 0: Dirac notation;

Section 1: The postulates of quantum mechanics

(lecture 1) - Section 2: Combining quantum systems: tensor products

(lecture 2) - Section 3: Non-locality and Bell inequalities

(lecture 3) - Section 4: Ensembles and density operators;

Section 5: Taking quantum systems apart: reduced states and the partial trace;

Section 6: A brief introduction to entropy

(lecture 4)

- Section 1: Angular Momentum and Spin

(lectures 1 and 2) - Section 2: Representations of Angular Momentum

(lectures 3 to 5) - Section 3: Orbital Anglular Momentum

(bonus lecture) - Section 4: Measurement

(lecture 6) - Section 5: Multiple Particles and Tensor Products

(lectures 7 and 8) - Section 6: Non-Locality and Bell Inequalities

(lectures 9 and 10)

Given that the question sheets are substantially re-used in subsequent semesters, I've removed the worked solutions that were available here, to help you avoid the temptation to…ahem…short-cut the valuable learning process that struggling to solve the questions provides. (Believe it or not, the question sheets are not some obscure form of torture dreamed up by bitter and twisted physics professors).

If anyone involved in teaching the courses is interested in obtaining the solutions, drop me an email. I have scanned copies for about half the mechanics question sheets and all the electrodynamics question sheets.