Can Effects of Dark Matter be Explained by the Turbulent Flow of Spacetime?

For the past forty years the search for dark matter has been one of the primary foci of astrophysics, although there has yet to be any direct evidence for its existence (Porter et al. 2011). Indirect evidence for the existence of dark matter is largely rooted in the rotational speeds of stars within their host galaxies, where, instead of having a ~ r^1/2 radial dependence, stars appear to have orbital speeds independent of their distance from the galactic center, which led to proposed existence of dark matter (Porter et al. 2011; Peebles 1993). We propose an alternate explanation for the observed stellar motions within galaxies, combining the standard treatment of a fluid-like spacetime with the possibility of a "bulk flow" of mass through the Universe. The differential "flow" of spacetime could generate vorticies capable of providing the "perceived" rotational speeds in excess of those predicted by Newtonian mechanics. Although a more detailed analysis of our theory is forthcoming, we find a crude "order of magnitude" calculation can explain this phenomena. We also find that this can be used to explain the graviational lensing observed around globular clusters like "Bullet Cluster".Comment: 5 pages, Accepted for publication in Journal of Modern Physics: Gravitation and Cosmology (Sept. 2012

Patterns of Aging in Thailand and Cote D'Ivoire

This paper is broadly concerned with the living standards of older people in two contrasting developing countries, Cote d'Ivoire and Thailand. We use a series of household surveys from these two countries to present evidence on factors affecting the living standards of the elderly: living arrangements, labor force participation, illness, urbanization, income and consumption. One of the issues we examine is whether life-cycle patterns of income aid consumption can be detected in the data. The fact that few of the elderly live alone makes it difficult to accurately measure the welfare levels of the elderly, or to make statements about the life-cycle patterns of income aid consumption of individuals. We find that labor force participation and individual income patterns follow the standard life-cycle hump shapes in both countries, but that avenge living standards within households are quite flat over the life-cycle. The data presented suggest that changes in family composition aid living arrangements of the elderly are likely to be more important sources of old-age insurance than asset accumulation.

The wedding of modified dynamics and non-exotic dark matter in galaxy clusters

We summarize the status of Modified Newtonian Dynamics (MOND) in galaxy clusters. The observed acceleration is typically larger than the acceleration threshold of MOND in the central regions, implying that some dark matter is necessary to explain the mass discrepancy there. A plausible resolution of this issue is that the unseen mass in MOND is in the form of ordinary neutrinos with masses just below the experimentally detectable limit. In particular, we show that the lensing mass reconstructions of the clusters 1E0657-56 (the bullet cluster) and Cl0024+17 (the ring) do not pose a new challenge to this scenario. However, the mass discrepancy for cool X-ray emitting groups, in which neutrinos cannot cluster, pose a more serious problem, meaning that dark baryons could present a more satisfactory solution to the problem of unseen mass in MOND clusters.Comment: to appear in World Scientific, proceedings of DARK 200

Should a doctor tell? : medical confidentiality in interwar England and Scotland

Medical confidentiality is integral to the doctor - patient relationship and an important element in efficient and effective medical practice. However, it is generally acknowledged that medical confidentiality can not be absolute. At times it must be broken in order to serve a ‘higher’ interest - be it public health or the legal justice system. Yet, very little is known about the historical evolution of the boundaries of medical confidentiality in Britain. The absence of detailed historical research on the subject has meant that contemporary writers have tended to use citations of the Hippocratic Oath or short quotations from key legal cases to place their work into longer term context. The current thesis provides a more detailed examination of the delineation of the boundaries of medical confidentiality during a period of intense debate - the interwar years of the twentieth century. The increase in state interest in the health of the population, the growth in divorce after the First World War and the prominence of the medical issues of venereal disease and abortion, all brought unprecedented challenges to the traditional concept of medical confidentiality. Having examined the, oft-cited, benchmark precedent for medical confidentiality from the late eighteenth century, the thesis proceeds to examine the ways in which medicine had changed by the interwar years. The high-point of the debate in the early 1920s is examined from the perspective of the three key interest groups - the Ministry of Health, the British Medical Association and the Lord Chancellor. Overall, the work provides insight into the historical delineation of medical confidentiality in Britain, both in statute and common law. As such it lends a longer-term context to current debates over the boundaries of medical confidentiality in the twenty-first century