Search arXiv⌕ Search

arXiv · 2312.12182

From local nets to Euler elements

Abstract

Various aspects of the geometric setting of Algebraic Quantum Field Theory (AQFT) models related to representations of the Poincaré group can be studied for general Lie groups, whose Lie algebra contains an Euler element, i.e., ad h is diagonalizable with eigenvalues in {-1,0,1}. This has been explored by the authors and their collaborators during recent years. A key property in this construction is the Bisognano-Wichmann property (thermal property for wedge region algebras) concerning the geometric implementation of modular groups of local algebras. In the present paper we prove that under a natural regularity condition, geometrically implemented modular groups arising from the Bisognano-Wichmann property, are always generated by Euler elements. We also show the converse, namely that in presence of Euler elements and the Bisognano-Wichmann property, regularity and localizability hold in a quite general setting. Lastly we show that, in this generalized AQFT, in the vacuum representation, under analogous assumptions (regularity and Bisognano-Wichmann), the von Neumann algebras associated to wedge regions are type III_1 factors, a property that is well-known in the AQFT context.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Vincenzo Morinelli, Karl-Hermann Neeb. 2023-12-19. From local nets to Euler elements. https://arxiv.org/abs/2312.12182

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

Simplicity of reduced crossed products

We characterize the simplicity of reduced crossed product C*-algebras in terms of stabilizer subgroups. Specifically, we prove that if $G$ is a countable group and $X$ is a minimal $G$-flow, then the reduced crossed product C*-algebra $\mathrm{C}(X) \times_λG$ is simple if and only if there is a point in $X$ with a C*-simple stabilizer subgroup. Further, these conditions are equivalent to a generic point in $X$ having a C*-simple stabilizer subgroup. We also provide an example demonstrating that this result does not extend to uncountable groups. This completely resolves a question of Ozawa.

math.OA↗

$\mathrm{C}^*$-selflessness of vigorous groups

We prove that countable groups which admit a faithful piecewise minimal-extremely-proximal action on the Cantor set are $\mathrm{C}^*$-selfless. In particular, topological full groups of second countable, Hausdorff, minimal, purely infinite, topologically principal, ample groupoids with compact unit spaces are $\mathrm{C}^*$-selfless. Examples include the Higman--Thompson groups and the Brin--Thompson groups.

math.OA↗

A computable wandering and tracelike vector for modular orbits in the Bergman space

We construct a function $Φ$ such that the orbit under the representation of PSL(2,Z) is an orthonormal basis for the Bergman space with weight $α=12$. Moreover, we show that $Φ$ is effectively computable as a holomorphic function on the upper half-plane (in the precise sense of computable analysis), by providing an effective procedure. This constructs a wandering and tracelike vector for PSL(2,Z), whose abstract existence was proved by Sir Vaughan Jones in his last paper, where the corresponding construction was left as a problem. The function is built using an orthonormalization and modularization method, and it displays modular reminiscencies, despite not being modular itself. provides a computable implementing vector for the abstract anti-isomorphism between the von Neumann algebra $M_{12}(Γ)$ and its commutant, which is generated, in Rădulescu's sense, by cusp-form Toeplitz operators, while Voiculescu's results provide a random matrix model for $M_{12}(Γ)$.

math.OA↗