16,201 research outputs found
[Review of] Paul R. Spickard. Mixed Blood-Intermarriage and Ethnic Identity in Twentieth-Century America
Just as the mixing of peoples has been a dominant theme in American social history, it has also been a compelling, if not controversial, theme in American social science. Sociologists have long recognized that intermarriage is an important social phenomenon in American society. Thus, early American social observers were drawn to study this area of social life. From Frederick Hoffman\u27s earliest studies of black/white couples in the late nineteenth century to W. E. B. Du Bois\u27s observations on intermarriage at the beginning of the twentieth century, the systematic study of inter-marriage stands as one of the initial starting points for American sociology
INTERNATIONALIZATION OF FOOD DISTRIBUTION: THE BANGLADESH EXPERIENCE
International Relations/Trade,
Insertion and deletion tolerance of point processes
We develop a theory of insertion and deletion tolerance for point processes. A process is insertion-tolerant if adding a suitably chosen random point results in a point process that is absolutely continuous in law with respect to the original process. This condition and the related notion of deletion-tolerance are extensions of the so-called finite energy condition for discrete random processes. We prove several equivalent formulations of each condition, including versions involving Palm processes. Certain other seemingly natural variants of the conditions turn out not to be equivalent. We illustrate the concepts in the context of a number of examples, including Gaussian zero processes and randomly perturbed lattices, and we provide applications to continuum percolation and stable matching
Modular Invariants and Twisted Equivariant K-theory II: Dynkin diagram symmetries
The most basic structure of chiral conformal field theory (CFT) is the
Verlinde ring. Freed-Hopkins-Teleman have expressed the Verlinde ring for the
CFT's associated to loop groups, as twisted equivariant K-theory. We build on
their work to express K-theoretically the structures of full CFT. In
particular, the modular invariant partition functions (which essentially
parametrise the possible full CFTs) have a rich interpretation within von
Neumann algebras (subfactors), which has led to the developments of structures
of full CFT such as the full system (fusion ring of defect lines), nimrep
(cylindrical partition function), alpha-induction etc. Modular categorical
interpretations for these have followed. For the generic families of modular
invariants (i.e. those associated to Dynkin diagram symmetries), we provide a
K-theoretic framework for these other CFT structures, and show how they relate
to D-brane charges and charge-groups. We also study conformal embeddings and
the E7 modular invariant of SU(2), as well as some families of finite group
doubles. This new K-theoretic framework allows us to simplify and extend the
less transparent, more ad hoc descriptions of these structures obtained
previously within CFT.Comment: 49 pages; more explanatory material added; minor correction
Optically Generated 2-Dimensional Photonic Cluster State from Coupled Quantum Dots
We propose a method to generate a two-dimensional cluster state of polarization encoded photonic qubits from two coupled quantum dot emitters. We combine the proposal for generating one-dimensional cluster state strings from a single dot, with a new proposal for an induced conditional phase gate between the two quantum dots. The entanglement between the two dots translates to entanglement between the two photonic cluster state strings. Further interpair coupling of the quantum dots using cavities and waveguides can lead to a two-dimensional cluster sheet, the importance of which stems from the fact that it is a universal resource for quantum computation. Analysis of errors indicates that our proposal is feasible with current technology. Crucially, the emitted photons need not have identical frequencies, and so there are no constraints on the resonance energies for the quantum dots
Poisson splitting by factors
Given a homogeneous Poisson process on with intensity
, we prove that it is possible to partition the points into two sets,
as a deterministic function of the process, and in an isometry-equivariant way,
so that each set of points forms a homogeneous Poisson process, with any given
pair of intensities summing to . In particular, this answers a
question of Ball [Electron. Commun. Probab. 10 (2005) 60--69], who proved that
in , the Poisson points may be similarly partitioned (via a
translation-equivariant function) so that one set forms a Poisson process of
lower intensity, and asked whether the same is possible for all . We do not
know whether it is possible similarly to add points (again chosen as a
deterministic function of a Poisson process) to obtain a Poisson process of
higher intensity, but we prove that this is not possible under an additional
finitariness condition.Comment: Published in at http://dx.doi.org/10.1214/11-AOP651 the Annals of
Probability (http://www.imstat.org/aop/) by the Institute of Mathematical
Statistics (http://www.imstat.org
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