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Machine learning techniques are rapidly being adopted into the field of quantum many-body physics including condensed matter theory experiment and quantum information science.  The steady increase in data being produced by highly-controlled quantum experiments brings the potential of machine learning algorithms to the forefront of scientific advancement.  Particularly exciting is the prospect of using machine learning for the discovery and design of quantum materials devices and computers.  In order to make progress the field must address a number of fundamental questions related to the challenges of studying many-body quantum mechanics using classical computing algorithms and hardware. The goal of this conference is to bring together experts in computational physics machine learning and quantum information to make headway on a number of related topics including: Data-drive quantum state reconstruction Machine learning strategies for quantum error correction Neural-network based wavefunctions Near-term prospects for data from quantum devices Machine learning for quantum algorithm discovery Registration for this event is now closed

Quantum field theory (QFT) is a universal language for theoretical physics describing the Standard Model gravity early universe inflation and condensed matter phenomena such as phase transitions superconductors and quantum Hall fluids. A triumph of 20th century physics was to understand weakly coupled QFTs: theories whose interactions can be treated as small perturbations of otherwise freely moving particles. However weakly coupled QFTs represent a tiny island in an ocean of possibilities. They cannot capture many of the most interesting and important physical phenomena from the strong nuclear force to high temperature superconductivity.The critical challenge for the 21st century is to understand and solve strongly coupled QFTs. Meeting this challenge will require new physical insight new mathematics and new computational tools. Our collaboration combines deep knowledge of novel non-perturbative techniques with a concrete plan for attacking the problem of strong coupling. The starting point is the astonishing discovery that in numerous physical systems there is a unique quantum field theory consistent with general principles of symmetry and quantum mechanics. By analyzing the full implications of these general principles one can make sharp predictions for physical observables without resorting to approximations.This strategy is called the Bootstrap the topic of this three week program.

Boundaries and defects play central roles in quantum field theory (QFT) both as means to make contact with nature and as tools to constrain and understand QFT itself. Boundaries in QFT can be used to model impurities and also the finite extent of sample sizes while interfaces allow for different phases of matter to interact in a controllable way. More formally these structures shed light on the structure of QFT by providing new examples of dualities and renormalization group flows.  Broadly speaking this meeting will focus on three areas: 1) formal and applied aspects of boundary and defect conformal field theory from anomalies and c-theorems to topological insulators 2) supersymmetry and duality from exact computations of new observables to the construction of new theories and 3) QFT in curved space and gravity from holographic computations of entanglement entropy to ideas in quantum information theory. Registration for this event is now open.

These lectures will cover a number of topics related to the role of symmetry principles in physics. After introducing some basic definitions and distinctions, we will look at the changing role of the relativity principle from Galileo to Einstein (in special and general relativity). In particular we raise doubts as to the wisdom of treating Einstein's 1905 route to special relativity based on the relativity principle as a template for a fundamental reformulation of quantum theory, as some have recently proposed. We then examine the nature and meaning of Noether's 1918 theorems for global and local symmetries, and discuss some recent applications of Noether's "first" theorem in quantum mechanics and electromagnetism. We finish with two case studies: (i) the Galilean (boost) symmetry of quantum mechanics, and (ii) the problem of the arrow of time in statistical mechanics based on time-reversal invariant dynamics. Each lecture will be followed by a period for discussion.

Classes will meet on Wednesdays at the Perimeter Institute for Theoretical Physics, starting on January 9, 2008. The first class meeting is from 10:30 am to 12:00 pm in the Bob Room. The second class meeting is from 4:00 pm to 5:30 pm in the Alice Room.

This course will provide an introduction to current research on the problem of time in quantum gravity and cosmology. This is one of the key problems that any successful quantum theory of gravity must solve. Different approaches to quantum gravity assume different answers to fundamental questions such as whether time is emergent or not, whether causality is emergent or not, and what is an observable in a theory of gravity. These problems have aspects which are technical as well as conceptual and philosophical aspects and we will discuss them all as well as their inter-relations. The course will begin with an introduction to the canonical formulation of general relativity and related dynamical systems. We will then study the standard material on the Hamiltonian quantization of general relativity and related time reparametrization invariant systems. This gives us the technical setting in which the problem of time is usually encountered in the contemporary literature on quantum gravity and quantum cosmology. Following this physical introduction we will read the key texts from the history of physics and philosophy concerning the meaning of time, such as Newton, Leibniz, Mach, Einstein etc. This will be followed by readings of papers and books from contemporary sources on this issue by physicists and philosophers. We will focus on two opposite views, the idea that time is emergent in quantum cosmology and the opposing idea that time is fundamental and is perhaps the only aspect of our macroscopic reality that is not emergent.