Entanglement in the interaction between two quantum oscillator systems

The fundamental quantum dynamics of two interacting oscillator systems are studied in two different scenarios. In one case, both oscillators are assumed to be linear, whereas in the second case, one oscillator is linear and the other is a non-linear, angular-momentum oscillator; the second case is, of course, more complex in terms of energy transfer and dynamics. These two scenarios have been the subject of much interest over the years, especially in developing an understanding of modern concepts in quantum optics and quantum electronics. In this work, however, these two scenarios are utilized to consider and discuss the salient features of quantum behaviors resulting from the interactive nature of the two oscillators, i.e., coherence, entanglement, spontaneous emission, etc., and to apply a measure of entanglement in analyzing the nature of the interacting systems. ... For the coupled linear and angular-momentum oscillator system in the fully quantum-mechanical description, we consider special examples of two, three, four-level angular momentum systems, demonstrating the explicit appearances of entanglement. We also show that this entanglement persists even as the coupled angular momentum oscillator is taken to the limit of a large number of levels, a limit which would go over to the classical picture for an uncoupled angular momentum oscillator

Determinants of Minority-White Differentials in Child Poverty

This paper uses data from the 1993-2001 March Current Population Survey to estimate the extent to which child living arrangements, parental work patterns, and immigration attributes shape racial and ethnic variation in child poverty. Results from multivariate analyses and a standardization technique reveal that parental work patterns as well as child living arrangements are especially consequential for black and Puerto-Rican economic circumstances. Child immigration generation and parental length of residence seem to play a detrimental role in shaping poverty among Asian, Mexican, and Central/South American children. We also found that the extent to which differences in the composition of and returns to parental resources determine white-minority economic gaps varies substantially across racial and ethnic lines. The social and economic implications of the findings for understanding racial and ethnic inequality are discussed in the final section of the article

Identity and Economic Performance

Reductions in the employment of less-skilled Americans during recent decades are often attributed to a deterioration in work values. That view is challenged. The key determinants have been deteriorating earnings opportunities and the poor's assimilation of mainstream values. Urbanization facilitates less-skilled workers' assimilation of preferences for high standards of living and egalitarian interpersonal relations found in advanced economic democracies. The rewards received in the competition for jobs become major affirmations or denials of the validity of self-perceptions. Demand for public respect induces people to avoid jobs perceived to be demeaning even as the proportion of such jobs increases. Traditional scientific data are combined with personal documents (autobiography and rap music) to construct subject-centered analyses of behavior. The data enrich the contextual basis for explaining behaviors of low-status men labeled the "malcontented." </jats:p

The Labor Market Status of Black Americans: 1939–1985

Among the empirical changes in the labor maket status of black Americans since 1939, three stand out: 1) three decades of rapid progress followed by two decades of relative stagnation in many aggregate measures of relative black earnings and incomes; 2) declining employment of black males; and 3) heightened inequality within the black population. Why has relative black employment fallen when blacks' wages and their access to occupations and to institutions of higher education have improved so much? To what extent may these changes be attributed to changes in discrimination and its consequences; changes and differences in skills; and changes in the relative wages of workers of different skills. Many of these issues remain important open questions. But we can conclude that changes in the economy during the past two decades have had particularly adverse effects on the demand for low-skilled workers. In particular, lowerskilled black males, who are disproportionately among those with the least educational achievements and attainments, appear to be in very low demand and may have responded to this low demand by withdrawing from the regular labor market. </jats:p