We will discuss the themes of measurement and symmetry in quantum field theory, including introductory lectures on the algebraic approach to QFT, and lectures on their philosophical aspects.

Algebraic QFT places strong emphasis on algebras of local observables. Its clear conceptual and technical framework has led to important progress, such as the rigorous perturbative construction of quantized gauge theories, and has been a recent focus in quantum gravitation.

The issue of measurement in QFT has long been a topic plagued by apparent paradoxes and inconsistencies; for example, an instantaneous wavefunction collapse is incompatible with relativity. Recently a new framework for understanding QFT measurement has been developed using insights from AQFT.

While the emphasis on local observables has been highly successful in AQFT, some observables of interest for a quantum field are not well-localised. Examples include 'dressed', relational or asymptotic observables in QED, more general Yang-Mills theories and quantum gravitation. A related challenge concerns the quantization of field theories on manifolds with boundaries and corners. Finally, from an operational viewpoint, how can such 'semi-local' observables be measured? 

The Spring School aims to familiarise early career researchers with these recent developments and the necessary tools to tackle these challenges in fundamental quantum field theory research.

Lecturers:

Chris Fewster (University of York)

Doreen Fraser (University of Waterloo)

Kasia Rejzner (University of York)

Michele Schiavina (University of Pavia)

Rainer Verch (University of Leipzig)

Guest speakers:

Leon Loveridge (University of South-Eastern Norway)

Aldo Riello (Perimeter Institute)