2,340 research outputs found
Towards Spinfoam Cosmology
We compute the transition amplitude between coherent quantum-states of
geometry peaked on homogeneous isotropic metrics. We use the holomorphic
representations of loop quantum gravity and the
Kaminski-Kisielowski-Lewandowski generalization of the new vertex, and work at
first order in the vertex expansion, second order in the graph (multipole)
expansion, and first order in 1/volume. We show that the resulting amplitude is
in the kernel of a differential operator whose classical limit is the canonical
hamiltonian of a Friedmann-Robertson-Walker cosmology. This result is an
indication that the dynamics of loop quantum gravity defined by the new vertex
yields the Friedmann equation in the appropriate limit.Comment: 8 page
Analisis Gambaran Peta Perjalanan Pasien di Pelayanan Rawat Jalan RS Kanker “Dharmais” Tahun 2014
Penelitian ini membahas tentang peta perjalanan pasien di pelayanan rawat jalan RS Kanker “Dharmais” pada tahun 2014. Dalam penelitian ini peneliti berusaha menemukan unit dengan variasi perjalanan pasien tertinggi dan mengidentifikasi faktor-faktor penyebabnya. Penelitian ini adalah penelitian dengan pendekatan kualitatif dan metode cross-sectional. Hasil penelitian ini menemukan bahwa variasi perjalanan pasien tertinggi berada di Instalasi Administrasi Pasien Jaminan (APJ) dengan faktor penyebab antara lain faktor program komputer penunjang, sumber daya manusia, infrastruktur hingga prosedur pelayanan. Penelitian ini juga menemukan bahwa variasi perjalanan pasien dapat mengurangi mutu pelayanan yang diberikan
Noncommutative geometry of angular momentum space U(su(2))
We study the standard angular momentum algebra as a noncommutative manifold . We show that
there is a natural 4D differential calculus and obtain its cohomology and Hodge
* operator. We solve the spin 0 wave equation and some aspects of the Maxwell
or electromagnetic theory including solutions for a uniform electric current
density, and we find a natural Dirac operator. We embed inside a
4D noncommutative spacetime which is the limit of q-Minkowski space
and show that has a natural quantum isometry group given by the
quantum double as a singular limit of the -Lorentz group. We
view as a collection of all fuzzy spheres taken together. We
also analyse the semiclassical limit via minimum uncertainty states
approximating classical positions in polar coordinates.Comment: Minor revision to add reference [11]. 37 pages late
Induced Representations of Quantum Kinematical Algebras and Quantum Mechanics
Unitary representations of kinematical symmetry groups of quantum systems are
fundamental in quantum theory. We propose in this paper its generalization to
quantum kinematical groups. Using the method, proposed by us in a recent paper
(olmo01), to induce representations of quantum bicrossproduct algebras we
construct the representations of the family of standard quantum inhomogeneous
algebras . This family contains the quantum
Euclidean, Galilei and Poincar\'e algebras, all of them in (1+1) dimensions. As
byproducts we obtain the actions of these quantum algebras on regular co-spaces
that are an algebraic generalization of the homogeneous spaces and --Casimir
equations which play the role of --Schr\"odinger equations.Comment: LaTeX 2e, 20 page
Generalized exclusion and Hopf algebras
We propose a generalized oscillator algebra at the roots of unity with
generalized exclusion and we investigate the braided Hopf structure. We find
that there are two solutions: these are the generalized exclusions of the
bosonic and fermionic types. We also discuss the covariance properties of these
oscillatorsComment: 10 pages, to appear in J. Phys.
Differential and Twistor Geometry of the Quantum Hopf Fibration
We study a quantum version of the SU(2) Hopf fibration and its
associated twistor geometry. Our quantum sphere arises as the unit
sphere inside a q-deformed quaternion space . The resulting
four-sphere is a quantum analogue of the quaternionic projective space
. The quantum fibration is endowed with compatible non-universal
differential calculi. By investigating the quantum symmetries of the fibration,
we obtain the geometry of the corresponding twistor space and
use it to study a system of anti-self-duality equations on , for which
we find an `instanton' solution coming from the natural projection defining the
tautological bundle over .Comment: v2: 38 pages; completely rewritten. The crucial difference with
respect to the first version is that in the present one the quantum
four-sphere, the base space of the fibration, is NOT a quantum homogeneous
space. This has important consequences and led to very drastic changes to the
paper. To appear in CM
An Electronically Reconfigurable Patch Antenna Design for Polarization Diversity with Fixed Resonant Frequency
In this paper, an electronically polarization reconfigurable circular patch antenna with fixed resonant frequency operating at Wireless Local Area Network (WLAN) frequency band (2.4-2.48 GHz) is presented. The structure of the proposed design consists of a circular patch as a radiating element fed by coaxial probe, cooperated with four equal-length slits etched on the edge along x-axis and y-axis. A total of four switches was used and embedded across the slits at specific locations, thus controlled the length of the slits. By activating and deactivating the switches (ON and OFF) across the slits, the current on the patch is changed, thus modifying the electric field and polarization of the antenna. Consequently, the polarization excited by the proposed antenna can be switched into three types, either linear polarization, left-hand circular polarization or right-hand circular polarization. This paper proposes a simple approach that able to switch the polarizations and excited at the same operating frequency. Simulated and measured results of ideal case (using copper strip switches) and real case (using PIN diode switches) are compared and presented to demonstrate the performance of the antenna
Representations of Quantum Bicrossproduct Algebras
We present a method to construct induced representations of quantum algebras
having the structure of bicrossproduct. We apply this procedure to some quantum
kinematical algebras in (1+1)--dimensions with this kind of structure:
null-plane quantum Poincare algebra, non-standard quantum Galilei algebra and
quantum kappa Galilei algebra.Comment: LaTeX 2e, 35 page
Relativistic Filamentation and Modulational Instabilities of a Laser Radiation in a Laser Produced Plasma
Physics of Quantum Relativity through a Linear Realization
The idea of quantum relativity as a generalized, or rather deformed, version
of Einstein (special) relativity has been taking shape in recent years.
Following the perspective of deformations, while staying within the framework
of Lie algebra, we implement explicitly a simple linear realization of the
relativity symmetry, and explore systematically the resulting physical
interpretations. Some suggestions we make may sound radical, but are arguably
natural within the context of our formulation. Our work may provide a new
perspective on the subject matter, complementary to the previous approach(es),
and may lead to a better understanding of the physics.Comment: 27 pages in Revtex, no figure; proof-edited version to appear in
Phys.Rev.
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