Notes on the Verlinde formula in non-rational conformal field theories

We review and extend evidence for the validity of a generalized Verlinde formula in particular non-rational conformal field theories. We identify a subset of representations of the chiral algebra in non-rational conformal field theories that give rise to an analogue of the relation between modular S-matrices and fusion coefficients in rational conformal field theories. To that end we review and extend the Cardy-type brane calculations in bosonic and supersymmetric Liouville theory (and its duals) as well as in the hyperbolic three-plane H3+. We analyze the three-point functions of Liouville theory and of H3+ in detail to directly identify the fusion coefficients from the operator product expansion.Comment: 29 pages, 6 figures, v2: minor corrections, PRD versio

094: Contribution of cardiac MRI to early evaluation and impact on the long term follow-up in myocarditis mimicking an acute coronary syndrome. A 43-cases prospective study

BackgroundAcute myocarditis (AM) diagnosis is a challenge to rule out an acute coronary syndrome (ACS). AM is thought to favour the evolution towards dilated cardiomyopathy (DCM) and the occurrence of severe arrhythmias. Three months after the acute episode, re-evaluation including cardiac MRI could help to identify patients at risk for unfavourable evolution. The use of MRI has rarely been investigated in AM prognosis stratification.Method and resultswe report a prospective series of 43 consecutive patients hospitalized for AM mimicking ACS: 36 men and 7 women, 32 years old on average, without sign of heart failure. All patients presented with troponine I elevation. Echocardiography showed moderate global left ventricular dysfunction in 6 cases and segmental wall motion abnormalities in 22. MRI performed early after admission never showed myocardial first-pass perfusion defect after gadolinium injection but subepicardial delayed-enhancement (DE) areas in 39 cases mainly located in lateral segments. Three months after the acute episode, no patient was symptomatic. Echocardiography, Holter monitoring and biological check-up were normal. MRI showed the persistence of DE in 23 cases without wall motion abnormality in the affected segments. The presence of these latter abnormalities led to effect an annually clinical examination with an ECG. One patient was lost at further follow-up. Among the other 22 patients, only one patient dysplayed heart failure revealing DCM with ventricular arrhythmias at 3 - year mean follow-up.Conclusionsat the time of admission, the absence of early perfusion defect at cardiac MRI after gadolinium injection and the subepicardial localization of the DE constitute reliable criteria in favour of AM diagnosis, allowing to rule out ACS. During the follow-up the persistence of a DE does not allow any prognosis stratification. In our series after a mean 3-year follow-up, it is not associated with any clinical and para-clinical disorder except in one case

Open strings in Lie groups and associative products

Firstly, we generalize a semi-classical limit of open strings on D-branes in group manifolds. The limit gives rise to rigid open strings, whose dynamics can efficiently be described in terms of a matrix algebra. Alternatively, the dynamics is coded in group theory coefficients whose properties are translated in a diagrammatical language. In the case of compact groups, it is a simplified version of rational boundary conformal field theories, while for non-compact groups, the construction gives rise to new associative products. Secondly, we argue that the intuitive formalism that we provide for the semi-classical limit, extends to the case of quantum groups. The associative product we construct in this way is directly related to the boundary vertex operator algebra of open strings on symmetry preserving branes in WZW models, and generalizations thereof, e.g. to non-compact groups. We treat the groups SU(2) and SL(2,R) explicitly. We also discuss the precise relation of the semi-classical open string dynamics to Berezin quantization and to star product theory.Comment: 47 pages, 14 figure

COVID-19 symptoms at hospital admission vary with age and sex: results from the ISARIC prospective multinational observational study

Background: The ISARIC prospective multinational observational study is the largest cohort of hospitalized patients with COVID-19. We present relationships of age, sex, and nationality to presenting symptoms. Methods: International, prospective observational study of 60 109 hospitalized symptomatic patients with laboratory-confirmed COVID-19 recruited from 43 countries between 30 January and 3 August 2020. Logistic regression was performed to evaluate relationships of age and sex to published COVID-19 case definitions and the most commonly reported symptoms. Results: ‘Typical’ symptoms of fever (69%), cough (68%) and shortness of breath (66%) were the most commonly reported. 92% of patients experienced at least one of these. Prevalence of typical symptoms was greatest in 30- to 60-year-olds (respectively 80, 79, 69%; at least one 95%). They were reported less frequently in children (≤ 18 years: 69, 48, 23; 85%), older adults (≥ 70 years: 61, 62, 65; 90%), and women (66, 66, 64; 90%; vs. men 71, 70, 67; 93%, each P < 0.001). The most common atypical presentations under 60 years of age were nausea and vomiting and abdominal pain, and over 60 years was confusion. Regression models showed significant differences in symptoms with sex, age and country. Interpretation: This international collaboration has allowed us to report reliable symptom data from the largest cohort of patients admitted to hospital with COVID-19. Adults over 60 and children admitted to hospital with COVID-19 are less likely to present with typical symptoms. Nausea and vomiting are common atypical presentations under 30 years. Confusion is a frequent atypical presentation of COVID-19 in adults over 60 years. Women are less likely to experience typical symptoms than men

Theories des champs conformes non rationnelles et applications a la theorie des cordes.

This dissertation is devoted to the study of certain non-rational conformal field theories which arise in the context of string theory. In contrast to rational conformal field theories, which have been extensively studied in the past few decades, non-rational theories are not yet well-understood. A better understanding is crucial in order to get a good grip on string theory in non-compact curved backgrounds, and eventually to address cosmological issues. Since the dissertation relies heavily on Lie group theory and conformal field theory, detailed introductions to these fields are provided for the reader who may not be familiar with them. The dissertation then moves on to a detailed presentation of the work that was done in the course of the PhD. This work dealt with pp-waves with Heisenberg symmetry, a Verlinde-like formula in non-rational conformal field theories (for instance in H_3^+), and rigid open strings whose endpoints live on co-adjoint orbits of Lie algebras.Cette these est dediee a l'etude de quelques theories conformes non rationnelles, qui apparaissent dans le cadre de la theorie des cordes. Contrairement aux theories conformes rationnelles, qui ont beneficie de tres nombreuses etudes dans les toutes dernieres decennies, les theories non rationnelles ne sont pas encore bien comprises. Une meilleure comprehension est pourtant necessaire pour mieux apprehender la theorie des cordes dans des fonds courbes non compacts, et pour pouvoir a terme s'attaquer a des problemes cosmologiques. Dans la mesure ou la these a frequemment recours a des notions et a des resultats de la theorie des groupes de Lie et de la theorie conforme des champs, des introductions detaillees a ces domaines sont presentees a l'attention des lecteurs qui ne sont pas familiarise avec eux. La these presente ensuite le travail qui a ete realise au cours du doctorat. Ce travail s'est attaque a des espaces presentant pour symetrie l'algebre de Heisenberg, a une extension de la formule de Verlinde pour des theories conformes non rationnelles (comme H_3^+), et aux cordes ouvertes rigides contraintes sur des orbites co-adjointes d'algebres de Lie

Théories des champs conformes non rationnelles et applications à la théorie des cordes

PALAISEAU-Polytechnique (914772301) / SudocSudocFranceF