Calabi-Yau Volumes and Reflexive Polytopes

We study various geometrical quantities for Calabi–Yau varieties realized as cones over Gorenstein Fano varieties, obtained as toric varieties from reflexive polytopes in various dimensions. Focus is made on reflexive polytopes up to dimension 4 and the minimized volumes of the Sasaki–Einstein base of the corresponding Calabi–Yau cone are calculated. By doing so, we conjecture new bounds for the Sasaki–Einstein volume with respect to various topological quantities of the corresponding toric varieties. We give interpretations about these volume bounds in the context of associated field theories via the AdS/CFT correspondence

From Clock Synchronization to Dark Matter as a Relativistic Inertial Effect

Lecture at BOSS2011 on relativistic metrology, on clock synchronization, relativistic dynamics and non-inertial frames in Minkowski spacetime, on relativistic atomic physics, on ADM canonical tetrad gravity in asymptotically Minkowskian spacetimes, on the York canonical basis identifying the inertial (gauge) and tidal degrees of freedom of the gravitational field, on the Post-Minkowskian linearization in 3-orthogonal gauges, on the Post-Newtonian limit of matter Hamilton equations, on the possibility to interpret dark matter as a relativistic inertial effect connected with relativistic metrology (i.e. clock synchronization) in Einstein GR.Comment: 90 pages. Lecture at BOSS201

Predictors of Persistent Symptoms in People in Coordinated Specialty Care Services for Early Psychosis in New York State

Objective: This study aimed to determine the prevalence and predictors of persistent transdiagnostic symptoms in the first year of enrollment in OnTrackNY, a coordinated specialty care (CSC) program for individuals with recent onset nonaffective psychosis. Methods: Three groups were defined by using the Mental Illness Research, Education, and Clinical Centers Global Assessment of Functioning symptom subscale: persistently symptomatic, intermittent, and improving to moderate. The authors compared groups on baseline demographic characteristics, family and living situation, clinical measures, and pathways to care. Results: Of 1,129 eligible participants, 12% were persistently symptomatic through follow-up. Being medication nonadherent, being homeless, having a diagnosis of schizophrenia, and having a longer duration between symptom onset and program enrollment were predictive of persistent symptoms during the first year of CSC. Conclusions: Findings suggest that despite intensive treatment, severe symptoms in young people with psychosis may persist because of economic barriers, treatment delays, and lack of stability. Psychiatric Services 2022; 73:92-95; doi: 10.1176/appi.ps.20200082

Tournament selection: Stable fitness pressure in XCS

Abstract. Although it is known from GA literature that proportionate selection is subject to many pitfalls, the LCS community somewhat adhered to proportionate selection. Also in the accuracy-based learning classifier system XCS, introduced by Wilson in 1995, proportionate selection is used. This paper identifies problem properties in which performance of proportionate selection is impaired. Consequently, tournament selection is introduced which makes XCS more parameter independent, noise independent, and more efficient in exploiting fitness guidance.