Gravitational Properties of Monopole Spacetimes Near the Black Hole Threshold

Although nonsingular spacetimes and those containing black holes are qualitatively quite different, there are continuous families of configurations that connect the two. In this paper we use self-gravitating monopole solutions as tools for investigating the transition between these two types of spacetimes. We show how causally distinct regions emerge as the black hole limit is achieved, even though the measurements made by an external observer vary continuously. We find that near-critical solutions have a naturally defined entropy, despite the absence of a true horizon, and that this has a clear connection with the Hawking-Bekenstein entropy. We find that certain classes of near-critical solutions display naked black hole behavior, although they are not truly black holes at all. Finally, we present a numerical simulation illustrating how an incident pulse of matter can induce the dynamical collapse of a monopole into an extremal black hole. We discuss the implications of this process for the third law of black hole thermodynamics.Comment: 23 pages, 4 figures RevTe

Test of catering theory for corporate dividend payout policy

Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2011.Cataloged from PDF version of thesis.Includes bibliographical references (p. [37]).We propose that the catering theory of dividends will not hold when tested with an extended sample period, different formulations of the dividend premium, and subsets of our sample divided by industry. The catering theory implies that managers cater to irrational and timevarying investor demand for dividends. This demand can be proxied by a dividend premium, a comparison of the market-to-book ratio of payers versus non-payers. The dividend premium that the catering model is based on suffers from a very arbitrary derivation. We find that coefficients for the regression of catering using an extended sample period and different derivations of the dividend premium give results with smaller economic and statistical significance. Furthermore, tests of our sample by industry show that the dividend premium, supposedly a market-wide measure that affects all firms, has different effects on various industries. Though the catering theory finds significance given a particular methodology, further analysis shows that the model is based on spurious correlation, and not true causation.by Alexander W. Lue.M.Eng