14,874 research outputs found
Inconsistencies in Interpreting the Atmospheric Neutrino Anomaly
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 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
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
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
In this paper we show that the mixing between leptoquarks (LQ's) from
different 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
.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
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 -function) in the combinatorial
-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
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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