570 research outputs found
New exact treatment of the perturbed Coulomb interactions
A novel method for the exact solvability of quantum systems is discussed and
used to obtain closed analytical expressions in arbitrary dimensions for the
exact solutions of the hydrogenic atom in the external potential , which is based on the recently introduced supersymmetric
perturbation theory.Comment: 6 pages article in LaTEX (uses standard article.sty). No Figures.
Please check "http://www1.gantep.edu.tr/~ozer/" for other studies of Nuclear
Physics Group at University of Gaziante
A coincidence point theorem for multi-valued contractions
A coincidence point theorem for two pairs of mappings is proved
An Upper Bound on the Higgs Boson Mass from a Positivity Condition on the Mass Matrix
We impose the condition that the eigenvalues of the mass matrix in the
shifted Lagrangian density be positive at \phi=\phi_{0}, the vacuum expectation
value of the scalar field. Using the one-loop effective potential of the
standard model, this condition leads to an upper bound on the Higgs boson mass
m_{H}: m_{H}<230GeV, for a top quark mass of 175GeV.Comment: LaTex, 5 page
Some results on a special type of real quadratic fields
In this paper, we determine the real quadratic fields Q(âd ) coincide with positive square - free integers d including the continued fraction expansion form of wd = [a0 ; 7,7,âŠ,7 l-1 , al]. Furthermore, we deal with determining fundamental units and Yokoiâs d -invariants nd and md in the relation to continued fraction expansion of wd where l( d ) is a period length of wd for the such type of real quadratic number fields Q(âd ) . The present paper improve the theory of fundamental unit which generates the unit group of real quadratic fields and also determine the special form of continued fraction expansion of integral basis element in real quadratic fields
International mobility of students - Its impact on labour market forecasts and its contribution to the Dutch economy
International student mobility has rapidly increased in the past three decades: the number of students enrolled in tertiary education outside of their country of citizenship was 0.8 million in 1975, but it increased to 4.3 million in 2011 (OECD, 2013).1 This rapid increase can be explained by several factors: internationalization and standardization of higher education (e.g., the Bologna process in European Union countries), global increase in demand for tertiary education, faster information flows thanks to the advancements in communication and transportation opportunities, and policies to encourage student exchange through bilateral agreements (Tremblay, 2005; OECD, 2013; Van Bouwel & Veugelers, 2013)
Minimal Scalar Sector of 3-3-1 Models without Exotic Electric Charges
We study the minimal set of Higgs scalars, for models based on the local
gauge group which do not contain
particles with exotic electric charges. We show that only two Higgs
triplets are needed in order to properly break the symmetry. The exact
tree-level scalar mass matrices resulting from symmetry breaking are calculated
at the minimum of the most general scalar potential, and the gauge bosons are
obtained, together with their couplings to the physical scalar fields. We show
how the scalar sector introduced is enough to produce masses for fermions in a
particular model which is an subgroup. By using experimental results we
constrain the scale of new physics to be above 1.3 TeV.Comment: LaTeX, 22 pages, 1 figure include
Rapid earthquake loss updating of spatially distributed systems via sampling-based bayesian inference
Within moments following an earthquake event, observations collected from the affected area can be used to define a picture of expected losses and to provide emergency services with accurate information. A Bayesian Network framework could be used to update the prior loss estimates based on ground-motion prediction equations and fragility curves, considering various field observations (i.e., evidence). While very appealing in theory, Bayesian Networks pose many challenges when applied to real-world infrastructure systems, especially in terms of scalability. The present study explores the applicability of approximate Bayesian inference, based on Monte-Carlo Markov-Chain sampling algorithms, to a real-world network of roads and built areas where expected loss metrics pertain to the accessibility between damaged areas and hospitals in the region. Observations are gathered either from free-field stations (for updating the ground-motion field) or from structure-mounted stations (for the updating of the damage states of infrastructure components). It is found that the proposed Bayesian approach is able to process a system comprising hundreds of components with reasonable accuracy, time and computation cost. Emergency managers may readily use the updated loss distributions to make informed decisions
Beta, Dipole and Noncommutative Deformations of M-theory Backgrounds with One or More Parameters
We construct new M-theory solutions starting from those that contain 5 U(1)
isometries. We do this by reducing along one of the 5-torus directions, then
T-dualizing via the action of an O(4,4) matrix and lifting back to
11-dimensions. The particular T-duality transformation is a sequence of O(2,2)
transformations embedded in O(4,4), where the action of each O(2,2) gives a
Lunin-Maldacena deformation in 10-dimensions. We find general formulas for the
metric and 4-form field of single and multiparameter deformed solutions, when
the 4-form of the initial 11-dimensional background has at most one leg along
the 5-torus. All the deformation terms in the new solutions are given in terms
of subdeterminants of a 5x5 matrix, which represents the metric on the 5-torus.
We apply these results to several M-theory backgrounds of the type AdS_r x
X^{11-r}. By appropriate choices of the T-duality and reduction directions we
obtain analogues of beta, dipole and noncommutative deformations. We also
provide formulas for backgrounds with only 3 or 4 U(1) isometries and study a
case, for which our assumption for the 4-form field is violated.Comment: v2:minor corrections, v3:small improvements, v4:conclusions expanded,
to appear in Class. Quant. Gra
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