1,250 research outputs found
Affine Sessions
Session types describe the structure of communications implemented by
channels. In particular, they prescribe the sequence of communications, whether
they are input or output actions, and the type of value exchanged. Crucial to
any language with session types is the notion of linearity, which is essential
to ensure that channels exhibit the behaviour prescribed by their type without
interference in the presence of concurrency. In this work we relax the
condition of linearity to that of affinity, by which channels exhibit at most
the behaviour prescribed by their types. This more liberal setting allows us to
incorporate an elegant error handling mechanism which simplifies and improves
related works on exceptions. Moreover, our treatment does not affect the
progress properties of the language: sessions never get stuck
Pinning quantum phase transition of photons in a hollow-core fiber
We show that a pinning quantum phase transition for photons could be observed
in a hollow-core one-dimensional fiber loaded with a cold atomic gas. Utilizing
the strong light confinement in the fiber, a range of different strongly
correlated polaritonic and photonic states, corresponding to both strong and
weak interactions can be created and probed. The key ingredient is the creation
of a tunable effective lattice potential acting on the interacting polaritonic
gas which is possible by slightly modulating the atomic density. We analyze the
relevant phase diagram corresponding to the realizable Bose-Hubbard (weak) and
sine-Gordon (strong) interacting regimes and conclude by describing the
measurement process. The latter consists of mapping the stationary excitations
to propagating light pulses whose correlations can be efficiently probed once
they exit the fiber using available optical technologiesComment: 4 pages, 4 figures. Comments welcome
Minority Education in Greece: Thrace Muslim Teachers’ Approaches and Views
In this paper, our focus is on the education of children from the Muslim Minority in Western Thrace, an administrative region of Greece. Education in Thrace is a sensitive issue that affects and is influenced by the bilateral relations between Greece and Turkey. More specifically, our research aimed to explore teachers of Muslim origins’ approaches, views and beliefs regarding Muslim students’ schooling. To this end, our research explored these issues in a Case Study using semi-structured interviews of Muslim teachers in Thrace. Our findings show that the policy of positive discrimination that had been applied to members of the Muslim Minority of Western Thrace for more than twenty years, has had positive results, but has now reached its limits. We believe that the findings of our research can inform policy makers, colleges and schools of education, as well as teachers by providing a better understanding of Muslim teachers’ prospects and needs
Minority Education in Greece: Thrace Muslim Teachers’ Approaches and Views
In this paper, our focus is on the education of children from the Muslim Minority in Western Thrace, an administrative region of Greece. Education in Thrace is a sensitive issue that affects and is influenced by the bilateral relations between Greece and Turkey. More specifically, our research aimed to explore teachers of Muslim origins’ approaches, views and beliefs regarding Muslim students’ schooling. To this end, our research explored these issues in a Case Study using semi-structured interviews of Muslim teachers in Thrace. Our findings show that the policy of positive discrimination that had been applied to members of the Muslim Minority of Western Thrace for more than twenty years, has had positive results, but has now reached its limits. We believe that the findings of our research can inform policy makers, colleges and schools of education, as well as teachers by providing a better understanding of Muslim teachers’ prospects and needs
The binding constraint on firms'growth in developing countries
Firms in developing countries face numerous and serious constraints on their growth, ranging from corruption to lack of infrastructure to inability to access finance. Countries lack the resources to remove all the constraints at once and so would be better off removing the most binding one first. This paper uses data from World Bank Enterprise Surveys in 2006-10 to identify the most binding constraints on firm operations in developing countries. While each country faces a different set of constraints, these constraints also vary by firm characteristics, especially firm size. Across all countries, access to finance is among the most binding constraints; other obstacles appear to matter much less. This result is robust for all regions. Smaller firms must rely more on their own funds to invest and would grow significantly faster if they had greater access to external funds. As a result, a low level of financial development skews the firm size distribution by increasing the relative share of small firms. The results suggest that financing constraints play a significant part in explaining the"missing middle"-- the failure of small firms in developing countries to grow into medium-size or large firms.Access to Finance,Environmental Economics&Policies,Microfinance,Debt Markets,Banks&Banking Reform
Simulating spin-charge separation with light
In this work we show that stationary light-matter excitations generated
inside a hollow one-dimensional waveguide filled with atoms, can be made to
generate a photonic two-component Lieb Liniger model. We explain how to prepare
and drive the atomic system to a strongly interacting regime where spin-charge
separation could be possible. We then proceed by explaining how to measure the
corresponding effective spin and charge densities and velocities through
standard optical methods based in measuring dynamically the emitted photon
intensities or by analyzing the photon spectrum. The relevant interactions
exhibit the necessary tunability both to generate and efficiently observe spin
charge separation with current technology.Comment: 4 pages. Comments welcom
Using Superconducting Qubit Circuits to Engineer Exotic Lattice Systems
We propose an architecture based on superconducting qubits and resonators for
the implementation of a variety of exotic lattice systems, such as spin and
Hubbard models in higher or fractal dimensions and higher-genus topologies.
Spin systems are realized naturally using qubits, while superconducting
resonators can be used for the realization of Bose-Hubbard models. Fundamental
requirements for these designs, such as controllable interactions between
arbitrary qubit pairs, have recently been implemented in the laboratory,
rendering our proposals feasible with current technology.Comment: 7 pages (two-column), 3 figure
- …