How to extract physics from HBT radius parameters

I review recent progress in the understanding of the connection between the space-time structure of the particle emitting source and the form of the two-particle correlation function in momentum space. Based on a new scheme for calculating the HBT radius parameters from the emission function, strategies are suggested to separate for rapidly expanding sources the information on the spatial and temporal structure of the source. To this end a new fitting function for the two-particle correlation function is proposed. Its usefulness is demonstrated for a typical expanding model source, and it is shown how the dependence of the resulting fit parameters on the momentum of the particle pair can be used to measure the longitudinal and transverse expansion of the source.Comment: 14 pages, 5 figures, LaTeX (qm96.sty included). Invited talk presented at Quark Matter 96, Heidelberg, 20.-24.5.9

Die finanzielle Globalisierung in der Kritik

Die Hauptkritik der Globalisierungsgegner zielt auf die internationalen Finänzmärkte. Welche Bedeutung haben die Finanzmärkte für die Weltwirtschaft? Was wird im einzelnen kritisiert? Ist die Kritik gerechtfertigt? --

Philosophie und Religion im antiken Konfuzianismus

Bei der Beschäftigung mit der Entstehungsphase der chinesischen Philosophie fällt auf, dass diese nur in äußerst geringem Umfang von religiösem Gedankengut beeinflusst war. Es gab zwar in der nicht systematisierten Volksreligion einen weit verbreiteten Glauben an Geister\ud und Dämonen, der jedoch in der Philosophie kaum nennenswerten Widerhall fand.\ud War also die Frage nach dem „letzten Grund“, die für die europäische Philosophie durchaus von zentraler Bedeutung war, für die chinesischen Philosophen nebensächlich? Wurden ihre ethischen Forderungen vom Volk verstanden, angenommen und verbreitet, ohne dass es des Anreizes durch jenseitige Belohnung bzw. Androhung von Strafe im Jenseits bedurft hätte?\ud Konnten sich philosophische Strömungen in der Bevölkerung ausbreiten, ohne dass ein sendungsbewusster Klerus diese Verbreitung unterstützte?\ud Die vorliegende Arbeit wird beispielhaft an Hand des antiken Konfuzianismus diesen Fragen nachgehen und versuchen, in der einschlägigen Fachliteratur Antworten zu finden

HBT Correlators -- Current Formalism vs. Wigner Function Formulation

We clarify the relationship between the current formalism developed by Gyulassy, Kaufmann and Wilson and the Wigner function formulation suggested by Pratt for the 2-particle correlator in Hanbury-Brown Twiss interferometry. When applied to a hydrodynamical description of the source with a sharp freeze-out hypersurface, our results remove a slight error in the prescription given by Makhlin and Sinyukov which has led to confusion in the literature.Comment: 8 pages, late

3D drucken mit Holz

3D-Druck auf Holzbasis – hierfür bündeln drei Forschungsinstitute der Berner Fachhochschule BFH und ein Wirtschaftspartner ihre Kompetenzen. Spannende Möglichkeiten für die Schreiner- und Holzbaubranche zeichnen sich ab, noch ist die Lösung indes in Arbeit

Exploring the biophysical option space for feeding the world without deforestation

Safeguarding the world’s remaining forests is a high priority goal. We assess the biophysical option space for feeding the world in 2050 in a hypothetical zero deforestation world. We systematically combine realistic assumptions on future yields, agricultural areas, livestock feed and human diets. For each scenario, we determine whether the supply of crop products meets the demand and whether the grazing intensity stays within plausible limits. We find that many options exist to meet the global food supply in 2050 without deforestation, even at low crop-yield levels. Within the option space, individual scenarios differ greatly in terms of biomass harvest, cropland demand and grazing intensity, depending primarily on the quantitative and qualitative aspects of human diets. Grazing constraints strongly limit the option space. Without the option to encroach into natural or semi-natural land, trade volumes will rise in scenarios with globally converging diets, thereby decreasing the food self-sufficiency of many developing regions

Corticothalamic projections control synchronization in locally coupled bistable thalamic oscillators

Thalamic circuits are able to generate state-dependent oscillations of different frequencies and degrees of synchronization. However, only little is known how synchronous oscillations, like spindle oscillations in the thalamus, are organized in the intact brain. Experimental findings suggest that the simultaneous occurrence of spindle oscillations over widespread territories of the thalamus is due to the corticothalamic projections, as the synchrony is lost in the decorticated thalamus. Here we study the influence of corticothalamic projections on the synchrony in a thalamic network, and uncover the underlying control mechanism, leading to a control method which is applicable in wide range of stochastic driven excitable units.Comment: 4 pages with 4 figures (Color online on p.3-4) include

Computer Aided Diagnosis of Clustered Microcalcifications Using Artificial Neural Nets

Objective: Development of a fully automated computer application for detection and classification of clustered microcalcifications using neural nets. Material and Methods: Mammographic films with clustered microcalcifications of known histology were digitized. All clusters were rated by two radiologists on a 3 point scale: benign, indeterminate and malignant. Automated detected clustered microcalcifications were clustered. Features derived from those clusters were used as input to 2 artificial neural nets: one was trained to identify the indeterminate clusters, whereas the second ANN classified the remaining clusters in benign or malignant ones. Performance evaluation followed the patient-based receiver operator characteristic analysis. Results: For identification of patients with indeterminate clusters a an Az-value of 0.8741 could be achieved. For the remaining patients their clusters could be classified as benign or malignant at an Az-value of 0.8749, a sensitivity of 0.977 and specificity of 0.471. Conclusions: A fully automated computer system for detection and classification of clustered microcalcifications was developed. The system is able to identify patients with indeterminate clusters, where additional investigations are recommended, and produces a reliable estimation of the biologic dignity for the remaining ones