995,213 research outputs found
Making global connections through dance film
Dance film communicates on a most basic level, eliminating barriers of language and geography. Through this accessible art form, one is able to experience a variety of global perspectives that tend to crystalize aspects of the universal human experience, promoting our sense of belonging to a global family
Chicago's global connections and challenges
Economic development - Midwest
Connections Between Local and Global Turbulence in Accretion Disks
We analyze a suite of global magnetohydrodynamic (MHD) accretion disk
simulations in order to determine whether scaling laws for turbulence driven by
the magnetorotational instability, discovered via local shearing box studies,
are globally robust. The simulations model geometrically-thin disks with zero
net magnetic flux and no explicit resistivity or viscosity. We show that the
local Maxwell stress is correlated with the self-generated local vertical
magnetic field in a manner that is similar to that found in local simulations.
Moreover, local patches of vertical field are strong enough to stimulate and
control the strength of angular momentum transport across much of the disk. We
demonstrate the importance of magnetic linkages (through the low-density
corona) between different regions of the disk in determining the local field,
and suggest a new convergence requirement for global simulations -- the
vertical extent of the corona must be fully captured and resolved. Finally, we
examine the temporal convergence of the average stress, and show that an
initial long-term secular drift in the local flux-stress relation dies away on
a time scale that is consistent with turbulent mixing of the initial magnetic
field.Comment: 8 Pages, 7 Figures ApJ, In Pres
African gateways : measuring airline connectivity change for Africa's global urban networks in the 2003-2009 period
This paper studies the globalization of major African cities through their changing insertion in global airline networks. As such, the paper adds to a growing body of literature that analyzes the role of infrastructure in the formation of world-city networks. We draw on a rich data source that provides longitudinal airline booking data, which can be directly linked up to the evolution of inter-urban networks at the African and global scale. Our results indicate that Johannesburg remains the major gateway to Africa, but other regional centers and in particular Cairo, Lagos, Casablanca and Nairobi are rapidly complementing Johannesburg in this role. The globalization of African cities is related to rapid network growth on the African continent, but is outrun by fast growth in terms of non-African connections. Among the latter, connections to Asia and the Middle East are rapidly gaining importance. In the end, the paper argues that SouthSouth connections are crucial for an understanding of the contemporary globalization of African cities
Strong Connections on Quantum Principal Bundles
A gauge invariant notion of a strong connection is presented and
characterized. It is then used to justify the way in which a global curvature
form is defined. Strong connections are interpreted as those that are induced
from the base space of a quantum bundle. Examples of both strong and non-strong
connections are provided. In particular, such connections are constructed on a
quantum deformation of the fibration . A certain class of strong
-connections on a trivial quantum principal bundle is shown to be
equivalent to the class of connections on a free module that are compatible
with the q-dependent hermitian metric. A particular form of the Yang-Mills
action on a trivial U\sb q(2)-bundle is investigated. It is proved to
coincide with the Yang-Mills action constructed by A.Connes and M.Rieffel.
Furthermore, it is shown that the moduli space of critical points of this
action functional is independent of q.Comment: AMS-LaTeX, 40 pages, major revision including examples of connections
over a quantum real projective spac
- âŠ