Key research themes
1. How does algebraic quantum field theory (AQFT) formulate quantum field theory in curved spacetime and ensure physically meaningful states?
This theme focuses on the algebraic formulation of quantum field theory on globally hyperbolic curved spacetimes. It studies how observable algebras are defined independently of a fixed Hilbert space, how Hadamard states characterize physically reasonable quasifree states, and the construction and properties of CCR algebras and symmetry-induced *-algebra homomorphisms. This is crucial for generalizing QFT beyond Minkowski spacetime while retaining mathematical rigor and physical interpretability.
2. What is the role of modular theory and non-commutative geometry in providing a deeper geometric and quantum structure to space-time within AQFT?
This theme investigates how Tomita-Takesaki modular theory and related operator-algebraic structures reveal hidden dynamics and geometric structures of quantum field theories, suggesting a noncommutative and modularly quantized space-time framework. The approach leverages modular automorphisms, KMS states, and generalizations of classical geometries (e.g. Tulczyjew double bundles, Hitchin-Gualtieri bundles) to link algebraic quantum gravity proposals to quantum geometry and offers speculation on 'quantum geometry' emerging directly from AQFT's modular data.
3. How can the algebraic formalism of quantum field theory link to more traditional quantum mechanics and abstract algebraic structures like Lie algebras and generalized functions?
This theme covers the connection between quantum field theory operators and canonical quantum mechanical operators, the role of algebraic structures such as Lie algebras in phase-space quantization, and the use of nonlinear generalized functions to properly capture nonlinear operations on distributions appearing in QFT. The insight here is bridging practical quantum computations with deep algebraic frameworks and extending the algebraic language (Weyl algebras, Wigner-Weyl-Moyal formalism) to broader algebraic and geometric contexts.