Study design Retrospective cohort study. Objective Bracing is an accepted standard therapy for idiopathic scoliosis at Cobb angle ranges between 25° and 40°. However, it is unclear, if a specifically tailored regimen of daytime and nighttime braces (= double brace) yields superior results compared to the standard treatment (single brace for day and night). Methods One-hundred-fifteen patients with adolescent idiopathic scoliosis (AIS) were assessed before initiation of bracing treatment and at the final follow-up 2 years after deposition of the brace. They were divided into two groups: double-brace group (n = 66, 4 male, 62 female, age 13.1 ± 1.9 (mean ± SD), primary curvature thoracic n = 35, lumbar n = 31) and single-brace group (n = 49, 8 male, 41 female, age 14.1 ± 1.9, primary curvature thoracic n = 18, lumbar n = 31). Each patient underwent clinical and radiological examinations and Cobb angles were measured. Results Both therapy regimens succeeded to either stop progression or improve scoliosis in over 85% of cases. The nighttime brace showed a significantly higher primary correction than the daytime brace. Nevertheless, there was no significant difference in treatment success in the 2-year follow-up (p = 0.58). Conclusion It seems to be sufficient to treat idiopathic scoliosis with one well-tailored brace for day- and nighttime.

<p dir="ltr">In holographic quantum field theories, a bulk geometric semiclassical spacetime emerges from strongly coupled interacting conformal field theories in one less spatial dimension. This is the celebrated AdS/CFT correspondence. The entanglement entropy of a boundary spatial subregion can be calculated as the area of a codimension two bulk surface homologous to the boundary subregion known as the RT surface. The bulk region contained within the RT surface is known as the entanglement wedge and bulk reconstruction tells us that any operator in the entanglement wedge can be reconstructed as a non-local operator on the corresponding boundary subregion. This notion that entanglement creates geometry is dubbed "ER=EPR'' and has been the driving force behind recent progress in quantum gravity research. In this thesis, we put together two results that use Tomita-Takesaki modular theory and quantum ergodic theory to make progress on contemporary problems in quantum gravity.</p><p dir="ltr">A version of the black hole information loss paradox is the inconsistency between the decay of two-point functions of probe operators in large AdS black holes and the dual boundary CFT calculation where it is an almost periodic function of time. We show that any von Neumann algebra in a faithful normal state that is quantum strong mixing (two-point functions decay) with respect to its modular flow is a type III₁ factor and the state has a trivial centralizer. In particular, for Generalized Free Fields (GFF) in a thermofield double (KMS) state, we show that if the two-point functions are strong mixing, then the entire algebra is strong mixing and a type III₁ factor settling a recent conjecture of Liu and Leutheusser.</p><p dir="ltr">The semiclassical bulk geometry that emerges in the holographic description is a pseudo-Riemannian manifold and we expect a local approximate Poincaré algebra. Near a bifurcate Killing horizon, such a local two-dimensional Poincaré algebra is generated by the Killing flow and the outward null translations along the horizon. We show the emergence of such a Poincaré algebra in any quantum system with modular future and past subalgebras in a limit analogous to the near-horizon limit. These are known as quantum K-systems and they saturate the modular chaos bound. We also prove that the existence of (modular) future/past von Neumann subalgebras also implies a second law of (modular) thermodynamics.</p>