Cosmology: a bird's eye view

In this essay we discuss the difference in views of the Universe as seen by two different observers. While one of the observers follows a geodesic congruence defined by the geometry of the cosmological model, the other observer follows the fluid flow lines of a perfect fluid with a linear equation of state. We point out that the information these observers collect regarding the state of the Universe can be radically different; while one observes a non-inflating ever-expanding ever-lasting universe, the other observer can experience a dynamical behaviour reminiscent to that of quintessence or even that of a phantom cosmology leading to a 'big rip' singularity within finite time (but without the need for exotic forms of matter).Comment: 5 pages; received an honorable mention in the Gravity Research Foundation Essay Competition, 200

Economic growth in low income countries: How the G20 can help to raise and sustain it

This paper aims to operationalise the G20 commitment to ensure that the benefits of global growth are shared with Low Income Countries. Growth is central to poverty reduction and the achievement of MDGs, and in developing countries it is episodic and volatile. However, while the current LICs have poor growth histories, the countries that started off the 1960s as LICs have had virtually the same average growth rates as other country groups. We review the evidence connecting long-run growth and growth accelerations and collapses to six areas of policy: trade, skills development, macro-stability, financial development, infrastructure investment and human development. Growth strategies have to be developed and owned by LIC governments and societies and they need to be tailored to individual country needs. However, there are some things which the G20 can do to help. We group these actions under three headings: mitigating downturns, boosting underlying growth rates and developing institutions and knowledge. A final annex describes how Korea’s spectacular growth strategy can be viewed through these lenses.growth, low income countries, G20

A-2000: Close air support aircraft design team

The US Air Force is currently faced with the problem of providing adequate close air support for ground forces. Air response to troops engaged in combat must be rapid and devastating due to the highly fluid battle lines of the future. The A-2000 is the result of a study to design an aircraft to deliver massive fire power accurately. The low cost A-2000 incorporates: large weapons payload; excellent maneuverability; all weather and terrain following capacity; redundant systems; and high survivability

Youth Smoking, Cigarette Prices, and Anti-Smoking Sentiment

In this paper, we develop a new direct measure of state anti-smoking sentiment and merge it with micro data on youth smoking in 1992 and 2000. The empirical results from the cross-sectional models show two consistent patterns: after controlling for differences in state anti-smoking sentiment, the price of cigarettes has a weak and statistically insignificant influence on smoking participation; and state anti-smoking sentiment appears to be a potentially important influence on youth smoking participation. The cross-sectional results are corroborated by results from discrete time hazard models of smoking initiation that include state fixed effects. However, there is evidence of price-responsiveness in the conditional cigarette demand by youth and young adult smokers.