Seiberg--Witten maps for SO(1,3)\boldsymbol{SO(1,3)} gauge invariance and deformations of gravity

A family of diffeomorphism-invariant Seiberg--Witten deformations of gravity is constructed. In a first step Seiberg--Witten maps for an SO(1,3) gauge symmetry are obtained for constant deformation parameters. This includes maps for the vierbein, the spin connection and the Einstein--Hilbert Lagrangian. In a second step the vierbein postulate is imposed in normal coordinates and the deformation parameters are identified with the components $\theta^{\mu\nu}(x)$ of a covariantly constant bivector. This procedure gives for the classical action a power series in the bivector components which by construction is diffeomorphism-invariant. Explicit contributions up to second order are obtained. For completeness a cosmological constant term is included in the analysis. Covariant constancy of $\theta^{\mu\nu}(x)$, together with the field equations, imply that, up to second order, only four-dimensional metrics which are direct sums of two two-dimensional metrics are admissible, the two-dimensional curvatures being expressed in terms of $\theta^{\mu\nu}$. These four-dimensional metrics can be viewed as a family of deformed emergent gravities.Comment: 1 encapsulated figur

Attitudes Towards Work and the Market Economy in the Czech and Slovak Republics

[Excerpt] This report is the final in a series of four reports whose main purpose is to present a preliminary overview of attitudes towards work and the market economy in four Eastern and Central European countries (actually five by now, following the division of Czechoslovakia into the Czech and the Slovak republics). The project was initiated by the Bureau of International Labor Affairs of the U.S. Department of Labor in mid-1991 in order to gather information which might assist in designing technical assistance programs appropriate for the new political and economic situation in these countries. Thus, the starting point was to develop a survey design and instrument which could illuminate the transition phase and how it is perceived in the population to conduct the surveys and to report their findings, as soon as possible, so as to allow for modifications in programs being planed or in operation

Attitudes Towards Work and the Market Economy in Hungary

[Excerpt] A common approach in describing countries in Eastern and Central Europe is to focus on similarities among them currently and in their past but to neglect differences. This approach utilizes broad categories as in seeing their economic systems as copies of the soviet model versus a Western free-market model . The principal focus is on delineating East-West differences. But to help Eastern and Central European countries overcome obstacles in this transition era, we need to understand distinctive country-characteristics and idiosyncrasies

Attitudes Towards Work And The Market Economy In Bulgaria

[Excerpt] As in the reports on Poland (Ruiz Quintanilla 1992a) and Hungary (Ruiz Quintanilla 1992b), this summary will center on how life has changed in Bulgaria as evaluated by the Bulgarian people. The domain of interest are attitudes and values related to the economy, work and political issues. The focus will be on where progress has been made and where, there has been regression. What are the hopes, intentions and plans for the future? How is the role of the West perceived? What kind of Western Assistance is wanted

Attitudes Towards Work and the Market Economy in Poland

[Excerpt] The results of the June, 1989 elections demonstrated the willingness of a majority of the Polish people to initiate the change from a one-party regime to political pluralism. While the past has been rejected, replacing a centrally planned economy with a market economy can neither be achieved overnight nor by simply by voting for it. The traces of the previous centrally planned economy as well as those of the autocratic political system still remain embedded in Polish work-organizations and institutions. Fragments of the former system have survived in the structure of the institutions, in daily routines and habits, and in the minds and conventions of the people

Black hole-naked singularity dualism and the repulsion of two Kerr black holes due to spin-spin interaction

We report about the possibility for interacting Kerr sources to exist in two different states - black holes or naked singularities - both states characterized by the same masses and angular momenta. Another surprising discovery reported by us is that in spite of the absence of balance between two Kerr black holes, the latter nevertheless can repel each other, which provides a good opportunity for experimental detection of the spin-spin repulsive force through the observation of astrophysical black-hole binaries.Comment: 5 pages, 2 figures: a misprint in formula (3) rectified; published versio