Birational motives, II: Triangulated birational motives

We develop birational versions of Voevodsky's triangulated categories of motives over a field, and relate them with the pure birational motives studied in arXiv:0902.4902 [math.AG]. We also get an interpretation of unramified cohomology in this framework, leading to "higher derived functors of unramified cohomology".Comment: Compared to the initial version: previous Subsection 4.2 has been upgraded to Section 5; previous Lemmas 5.2.5 and 5.2.6 have been corrected to Proposition 6.2.5 and Lemma 6.2.6; at the referee's request, previous Appendix B and the proof of previous Proposition C.1.1 (now A.4.1) have been removed (please consult the initial version for them

A few localisation theorems

Given a functor $T:C \to D$ carrying a class of morphisms $S\subset C$ into a class $S'\subset D$, we give sufficient conditions in order that $T$ induces an equivalence on the localised categories. These conditions are in the spirit of Quillen's theorem A. We give some applications in algebaic and birational geometry.Comment: File mistake in Version 2 To appear in Homology, Homotopy and Application

Wage-Employment Contracts: Global Results

This paper studies the efficient agreements about the dependence of workers' earnings on employment, when the employment level is controlled by firms. The firms ' superior information about profitability conditions is responsible for this form of contract governance. Under plausible assumptions, such agreements will cause employment to diverge from efficiency as a byproduct of their attempt to mitigate risk. It is shown that, if leisure is a normal good and firms are risk neutral, employment is always above the efficient level. Such a one-period implicit contracting model cannot, therefore, be used to "explain" unemployment as a rational byproduct of risk sharing between workers and a risk neutral firm under conditions of asymmetric information.

The Aesthetic Uncanny: Staging Dorian Gray

This article discusses my theatrical adaptation of Oscar Wilde's The Picture of Dorian Gray (1891) for the Edinburgh Festival Fringe (2008). Freud's concept of the uncanny (1919) was treated as a purely aesthetic phenomenon and related to late nineteenth century social and literary preoccupations such as Christianity, the supernatural and glamorous, criminal homosexuality. These considerations led to a conceptual ground plan that allowed for experiments during rehearsal in a form of theatrical shorthand

Strategies for estimating the marine geoid from altimeter data

In processing altimeter data from a spacecraft borne altimeter to estimate the fine structure of the marine geoid, a problem is encountered. In order to describe the geoid fine structure, a large number of parameters must be employed and it is not possible to simultaneously estimate all of them. Unless the parameterization exhibits good orthogonality in the data, serious aliasing results. From simulation studies it has been found that amongst several competing parameterizations, the mean free air gravity anomaly model (i.e., Stokes' formula) exhibited promising geoid recovery characteristics. Using covariance analysis techniques, this report provides quantitative measures of the orthogonality properties associated with the above mentioned parameterization. It has been determined that a 5 deg x 5 deg area mean free air gravity anomaly can be estimated with an uncertainty of 1 mgal (40 cm undulation) provided that all free air gravity anomalies within a spherical radius of 10 arc degrees are simultaneously estimated

Strategies for estimating the marine geoid from altimeter data

Altimeter data from a spacecraft borne altimeter was processed to estimate the fine structure of the marine geoid. Simulation studies show that, among several competing parameterizations, the mean free air gravity anomaly model exhibited promising geoid recovery characteristics. Using covariance analysis techniques, quantitative measures of the orthogonality properties are investigated