Evaluating the Extent and Nature of ‘Envelope Wages’ in the European Union: A Geographical Analysis

To evaluate the spatialities of the illegal wage practice where employers pay their declared employees both an official declared wage and an undeclared ‘envelope’ wage so as to avoid tax liabilities, a 2007 survey conducted in 27 European Union (EU) member states is reported. The finding is that 5% of employees received envelope wages which amount on average to some two-fifths of their wage packet. Revealing how, although heavily concentrated in a small group of East-Central European nations, this wage practice is nonetheless ubiquitous, the paper concludes by discussing how this practice might be tackled

Explaining Cross-National Variations in the Prevalence and Character of Undeclared Employment in the European Union

The aim of this article is to evaluate the competing theories that variously explain the greater prevalence of undeclared employment in some countries either as: a legacy of under-development; a result of the voluntary exit from declared employment due to the high taxes, state corruption and burdensome regulations and controls, or a product of a lack of state intervention in work and welfare which leads to the exclusion of workers from the declared economy and state welfare provision. Analyzing the cross-national variations in the prevalence of, and reasons for, undeclared employment across the European Union using evidence from a 2007 Eurobarometer survey, the finding is that undeclared employment is less prevalent and more of the voluntary variety in wealthier, less corrupt and more equal societies possessing higher levels of social protection and redistribution via social transfers. The theoretical and policy implications are then discussed

Neutron irradiation of Linde sieve 13-X

Imperial Users onl

Generalized Quantum Search with Parallelism

We generalize Grover's unstructured quantum search algorithm to enable it to use an arbitrary starting superposition and an arbitrary unitary matrix simultaneously. We derive an exact formula for the probability of the generalized Grover's algorithm succeeding after n iterations. We show that the fully generalized formula reduces to the special cases considered by previous authors. We then use the generalized formula to determine the optimal strategy for using the unstructured quantum search algorithm. On average the optimal strategy is about 12% better than the naive use of Grover's algorithm. The speedup obtained is not dramatic but it illustrates that a hybrid use of quantum computing and classical computing techniques can yield a performance that is better than either alone. We extend the analysis to the case of a society of k quantum searches acting in parallel. We derive an analytic formula that connects the degree of parallelism with the optimal strategy for k-parallel quantum search. We then derive the formula for the expected speed of k-parallel quantum search.Comment: 14 pages, 2 figure

<i>Kontakte</i> with piano and percussion

I designed and carried out performance of the Sound Projection for a public performance of Karlheinz Stockhausen's "Kontakte" with piano and percussion, featuring Nicolas Hodges on piano and Colin Currie on percussion at the Old Fruitmarket, Glasgow City Halls

Optimal Quantum Circuits for General Two-Qubit Gates

In order to demonstrate non-trivial quantum computations experimentally, such as the synthesis of arbitrary entangled states, it will be useful to understand how to decompose a desired quantum computation into the shortest possible sequence of one-qubit and two-qubit gates. We contribute to this effort by providing a method to construct an optimal quantum circuit for a general two-qubit gate that requires at most 3 CNOT gates and 15 elementary one-qubit gates. Moreover, if the desired two-qubit gate corresponds to a purely real unitary transformation, we provide a construction that requires at most 2 CNOTs and 12 one-qubit gates. We then prove that these constructions are optimal with respect to the family of CNOT, y-rotation, z-rotation, and phase gates.Comment: 6 pages, 8 figures, new title, final journal versio