2,289 research outputs found
On invariants of graphs related to quantum at roots of unity
We show how to define invariants of graphs related to quantum
when the graph has more then one connected component and
components are colored by blocks of representations with zero quantum
dimensions
Capabilities and Governance the Rebirth of Production in the Theory of Economic Organization
We argue that since Coase’s seminal 1937 paper on “The Nature of the Firm,” there has been an odd and unjustified separation between price theory and the economics of organization. For example, matters of production has been the domain of the former exclusively. However, a new approach to economic organization, here called “the capabilities approach,” that places production center-stage in the explanation of economic organization, is now emerging. We discuss the sources of this approach and its relation to the mainstream economics of organization.Capability, Theory of the Firm, Price Theory
Introduction to \u3ci\u3eThe Tragedy of Ukraine: What Classical Greek Tragedy Can Teach Us About Conflict Resolution\u3c/i\u3e
Introduction and table of contents to The Tragedy of Ukraine: What Classical Greek Tragedy Can Teach Us About Conflict Resolution by Nicolai N. Petro. Forthcoming, 2023
Entanglement generation in relativistic quantum fields
We present a general, analytic recipe to compute the entanglement that is
generated between arbitrary, discrete modes of bosonic quantum fields by
Bogoliubov transformations. Our setup allows the complete characterization of
the quantum correlations in all Gaussian field states. Additionally, it holds
for all Bogoliubov transformations. These are commonly applied in quantum
optics for the description of squeezing operations, relate the mode
decompositions of observers in different regions of curved spacetimes, and
describe observers moving along non-stationary trajectories. We focus on a
quantum optical example in a cavity quantum electrodynamics setting: an
uncharged scalar field within a cavity provides a model for an optical
resonator, in which entanglement is created by non-uniform acceleration. We
show that the amount of generated entanglement can be magnified by initial
single-mode squeezing, for which we provide an explicit formula. Applications
to quantum fields in curved spacetimes, such as an expanding universe, are
discussed.Comment: 8 pages, 2 figures, Ivette Fuentes previously published as Ivette
Fuentes-Guridi and Ivette Fuentes-Schuller; v2: published version (online),
to appear in the J. Mod. Opt. Special Issue on the Physics of Quantum
Electronic
Optical properties of apple skin and flesh in the wavelength range from 350 to 2200 nm
Optical measurement of fruit quality is challenging due to the presence of a skin around the fruit flesh and the multiple scattering by the structured tissues. To gain insight in the light-tissue interaction, the optical properties of apple skin and flesh tissue are estimated in the 350-2200nm range for three cultivars. For this purpose, single integrating sphere measurements are combined with inverse adding- doubling. The observed absorption coefficient spectra are dominated by water in the near infrared and by pigments and chlorophyll in the visible region, whose concentrations are much higher in skin tissue. The scattering coefficient spectra show the monotonic decrease with increasing wavelength typical for biological tissues with skin tissue being approximately three times more scattering than flesh tissue. Comparison to the values from time-resolved spectroscopy reported in literature showed comparable profiles for the optical properties, but overestimation of the absorption coefficient values, due to light losses
Central Solenoid Insert Technical Specification
The US ITER Project Office (USIPO) is responsible for the ITER central solenoid (CS) contribution to the ITER project. The Central Solenoid Insert (CSI) project will allow ITER validation the appropriate lengths of the conductors to be used in the full-scale CS coils under relevant conditions. The ITER Program plans to build and test a CSI to verify the performance of the CS conductor. The CSI is a one-layer solenoid with an inner diameter of 1.48 m and a height of 4.45 m between electric terminal ends. The coil weight with the terminals is approximately 820 kg without insulation. The major goal of the CSI is to measure the temperature margin of the CS under the ITER direct current (DC) operating conditions, including determining sensitivity to load cycles. Performance of the joints, ramp rate sensitivity, and stability against thermal or electromagnetic disturbances, electrical insulation, losses, and instrumentation are addressed separately and therefore are not major goals in this project. However, losses and joint performance will be tested during the CSI testing campaign. The USIPO will build the CSI that will be tested at the Central Solenoid Model Coil (CSMC) Test Facility at the Japan Atomic Energy Agency (JAEA), Naka, Japan. The industrial vendors (the Suppliers) will report to the USIPO (the Company). All approvals to proceed will be issued by the Company, which in some cases, as specified in this document, will also require the approval of the ITER Organization. Responsibilities and obligations will be covered by respective contracts between the USIPO, called Company interchangeably, and the industrial Prime Contractors, called Suppliers. Different stages of work may be performed by more than one Prime Contractor, as described in this specification. Technical requirements of the contract between the Company and the Prime Contractor will be covered by the Fabrication Specifications developed by the Prime Contractor based on this document and approved by the Company and ITER. The Fabrication Specifications may reflect some national requirements and regulations that are not fully provided here. This document presents the ITER CSI specifications
Vacua of N=10 three dimensional gauged supergravity
We study scalar potentials and the corresponding vacua of N=10 three
dimensional gauged supergravity. The theory contains 32 scalar fields
parametrizing the exceptional coset space . The admissible gauge groups considered in this work involve both
compact and non-compact gauge groups which are maximal subgroups of
and , respectively. These gauge groups are
given by for , , , and . We
find many AdS critical points with various unbroken gauge symmetries. The
relevant background isometries associated to the maximally supersymmetric
critical points at which all scalars vanish are also given. These correspond to
the superconformal symmetries of the dual conformal field theories in two
dimensions.Comment: 37 pages no figures, typos corrected and a little change in the
forma
Estimaci?n de par?metros para un modelo de regresi?n difusa simple
88 p. Recurso Electr?nic
Gradient Representations and Affine Structures in AE(n)
We study the indefinite Kac-Moody algebras AE(n), arising in the reduction of
Einstein's theory from (n+1) space-time dimensions to one (time) dimension, and
their distinguished maximal regular subalgebras sl(n) and affine A_{n-2}^{(1)}.
The interplay between these two subalgebras is used, for n=3, to determine the
commutation relations of the `gradient generators' within AE(3). The low level
truncation of the geodesic sigma-model over the coset space AE(n)/K(AE(n)) is
shown to map to a suitably truncated version of the SL(n)/SO(n) non-linear
sigma-model resulting from the reduction Einstein's equations in (n+1)
dimensions to (1+1) dimensions. A further truncation to diagonal solutions can
be exploited to define a one-to-one correspondence between such solutions, and
null geodesic trajectories on the infinite-dimensional coset space H/K(H),
where H is the (extended) Heisenberg group, and K(H) its maximal compact
subgroup. We clarify the relation between H and the corresponding subgroup of
the Geroch group.Comment: 43 page
Is Galactic Structure Compatible with Microlensing Data?
We generalize to elliptical models the argument of Kuijken (1997), which
connects the microlensing optical depth towards the Galactic bulge to the
Galactic rotation curve. When applied to the latest value from the MACHO
collaboration for the optical depth for microlensing of bulge sources, the
argument implies that the Galactic bar cannot plausibly reconcile the measured
values of the optical depth, the rotation curve and the local mass density.
Either there is a problem with the interpretation of the microlensing data, or
our line of sight to the Galactic centre is highly atypical in that it passes
through a massive structure that wraps only a small distance around the
Galactic centre.Comment: Submitted to ApJ Letters. 8 pages LaTeX, 3 figures. Corrected error
in description of microlensing observation
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