14,874 research outputs found

    Inconsistencies in Interpreting the Atmospheric Neutrino Anomaly

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    We note a discrepancy between the value of R expected on the basis of the muon neutrino angular distribution and the value actually observed. The energy independence of RR leads to a fine tuning problem. This may be indicative of some unaccounted for new physics.Comment: 3 pages, 5 figure

    A Closer Look at the Elementary Fermions

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    Although there have been many experimental and theoretical efforts to measure and interpret small deviations from the standard model of particle physics, the gap that the model leaves in understanding why there are only three generations of elementary fermions, with hierarchical masses, has not received the attention it deserves. I present here an attempt to fill this gap. Although our findings are mostly only qualitative, they nevertheless may be of heuristic value. Rules concerning the elementary fermions, some previously known and some new, lead to a number of conclusions and questions that seem worth pursuing. Some clarify the standard model, and others suggest possible modifications, the implications of which are discussed.Comment: 8 page

    Simplifying additivity problems using direct sum constructions

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    We study the additivity problems for the classical capacity of quantum channels, the minimal output entropy and its convex closure. We show for each of them that additivity for arbitrary pairs of channels holds iff it holds for arbitrary equal pairs, which in turn can be taken to be unital. In a similar sense, weak additivity is shown to imply strong additivity for any convex entanglement monotone. The implications are obtained by considering direct sums of channels (or states) for which we show how to obtain several information theoretic quantities from their values on the summands. This provides a simple and general tool for lifting additivity results.Comment: 5 page

    Neutrino masses and mixing angles from leptoquark interactions

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    In this paper we show that the mixing between leptoquarks (LQ's) from different SU(2)lSU(2)_l multiplets can generate a non-trivial Majorana mass matrix for neutrinos through one loop self energy diagrams. Such mixing can arise from gauge invariant and renormalizable LQ-Higgs interaction terms after EW symmetry breaking. We use the experimental indication on neutrino oscillation to find constraints on specific combinations of LQ couplings to quark-lepton pairs and to the SM higgs boson. These constraints are compared with the ones from π→eνˉe\pi\to e\bar {\nu}_e.Comment: The expressions for majorana mass matrix of neutrinos have been corrected so that they are symmetric. Final version to be published in Physical Review

    Energy Functions in Box Ball Systems

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    The box ball system is studied in the crystal theory formulation. New conserved quantities and the phase shift of the soliton scattering are obtained by considering the energy function (or HH-function) in the combinatorial RR-matrix.Comment: 15 pages, LaTeX2e: one paragraph replaced and reference added in Introduction, a paragraph added in Section 2.5, remark 2) after Th 4.6 adde

    Differential Input from the Amygdaloid Body to the Ventromedial Hypothalamic Nucleus in the Rat

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    Differential amygdaloid afferents to anterior dorsal, anterior ventral, posterior dorsal and posterior ventral subdivisions of the ventromedial hypothalamic nucleus (VMH) were studied by means of retrograde transport of horseradish peroxidase (HRP). Injections of tracer confined to the VMH subdivisions mentioned, and enhancement of tracer uptake and transport were achieved by iontophoretic delivery of an HRP solution containing poly-L-α-ornithine. It was shown that the medial, central, basolateral, basomedial, lateroposterior and intercalated nuclei of the amygdala constitute afferent input sources to the ventromedial nucleus in a topographic pattern related to the various subdivisions of the VMH. This topographically organized amygdala-VMH projection is discussed against the background of the functional role that both amygdala and VMH play in the control of feeding, apart from various other autonomous functions that both brain centers are known to be concerned with.
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