Metaspin and dirishonic dark matter

The antisymmetry requirement of rishon bound state wave functions suggests a new rishon quantum number called M spin. From M spin conservation and the Nussinov-Weingarten-Witten theorem we predict the existence of a stable pseudoscalar dirishonic meson, called zeta, that is lighter than the lightest neutrino. Its mass is estimated as m(zeta) = 10^{-9} eV. This particle could make up the major part of cold dark matter in the Universe.Comment: 8 pages, 1 figur

09221 Abstracts Collection -- Algorithms and NumberTheory

From 24.05. to 29.05.2009, the Dagstuhl Seminar 09221 ``Algorithms and Number Theory \u27\u27 was held in Schloss Dagstuhl~--~Leibniz Center for Informatics. During the seminar, several participants presented their current research, and ongoing work and open problems were discussed. Abstracts of the presentations given during the seminar as well as abstracts of seminar results and ideas are put together in this paper. The first section describes the seminar topics and goals in general. Links to extended abstracts or full papers are provided, if available

Deckungsbeiträge

Der Deckungsbeitrag (DB) ist die Differenz zwischen Leistung und variablen Kosten eines Produktionszweiges. Der DB muss die Gemeinkosten abdecken. Gemeinkosten sind Kosten, die nicht schlüsselungsfrei einem bestimmten Kostenträger (Betriebszweig) zugeteilt werden können. Die Berechnung des Deckungsbeitrages erfolgt nicht nach genauen Regeln. Sie richtet sich vielmehr nach der konkreten Problemstellung. Je nach Planungshorizont werden beispielsweise mehr oder weniger Kostenpositionen miteinbezogen. Hingegen ist die Berechnung des vergleichbaren Deckungsbeitrages (alt DfE) exakt definiert

Plant diversity effects on forage quality, yield and revenues of semi-natural grasslands

In agricultural settings, plant diversity is often associated with low biomass yield and forage quality, while biodiversity experiments typically find the opposite. We address this controversy by assessing, over 1 year, plant diversity effects on biomass yield, forage quality (i.e. nutritive values), quality-adjusted yield (biomass yield × forage quality), and revenues across different management intensities (extensive to intensive) on subplots of a large-scale grassland biodiversity experiment. Plant diversity substantially increased quality-adjusted yield and revenues. These findings hold for a wide range of management intensities, i.e., fertilization levels and cutting frequencies, in semi-natural grasslands. Plant diversity was an important production factor independent of management intensity, as it enhanced quality-adjusted yield and revenues similarly to increasing fertilization and cutting frequency. Consequently, maintaining and reestablishing plant diversity could be a way to sustainably manage temperate grasslands

Brain volumes predict neurodevelopment in adolescents after surgery for congenital heart disease

Patients with complex congenital heart disease are at risk for neurodevelopmental impairments. Evidence suggests that brain maturation can be delayed and pre- and postoperative brain injury may occur, and there is limited information on the long-term effect of congenital heart disease on brain development and function in adolescent patients. At a mean age of 13.8 years, 39 adolescent survivors of childhood cardiopulmonary bypass surgery with no structural brain lesions evident through conventional cerebral magnetic resonance imaging and 32 healthy control subjects underwent extensive neurodevelopmental assessment and cerebral magnetic resonance imaging. Cerebral scans were analysed quantitatively using surface-based and voxel-based morphometry. Compared with control subjects, patients had lower total brain (P = 0.003), white matter (P = 0.004) and cortical grey matter (P = 0.005) volumes, whereas cerebrospinal fluid volumes were not different. Regional brain volume reduction ranged from 5.3% (cortical grey matter) to 11% (corpus callosum). Adolescents with cyanotic heart disease showed more brain volume loss than those with acyanotic heart disease, particularly in the white matter, thalami, hippocampi and corpus callosum (all P-values < 0.05). Brain volume reduction correlated significantly with cognitive, motor and executive functions (grey matter: P < 0.05, white matter: P < 0.01). Our findings suggest that there are long-lasting cerebral changes in adolescent survivors of cardiopulmonary bypass surgery for congenital heart disease and that these changes are associated with functional outcom

Proposal for Quantum Simulation via All-Optically Generated Tensor Network States

We devise an all-optical scheme for the generation of entangled multimode photonic states encoded in temporal modes of light. The scheme employs a nonlinear down-conversion process in an optical loop to generate one- and higher-dimensional tensor network states of light. We illustrate the principle with the generation of two different classes of entangled tensor network states and report on a variational algorithm to simulate the ground-state physics of many-body systems. We demonstrate that state-of-the-art optical devices are capable of determining the ground-state properties of the spin-1/2 Heisenberg model. Finally, implementations of the scheme are demonstrated to be robust against realistic losses and mode mismatch.Comment: 6 pages main text plus 6 pages Supplementary Material and many figures. Updated to published version. Comments welcom

Quantum mutual information and the one-time pad

Alice and Bob share a correlated composite quantum system AB. If AB is used as the key for a one-time pad cryptographic system, we show that the maximum amount of information that Alice can send securely to Bob is the quantum mutual information of AB.Comment: 11 pages, LaTe