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Extensions to general relativity are often considered as possibilities in the quest for a quantum theory of gravity on one hand, or to resolve anomalies within cosmology on the other. Scalar fields, found in many areas of physics, are frequently studied in this context. This is partly due to their manifestation in the effective four dimensional theory of a number of underlying fundamental theories, most notably string theory. This thesis is concerned with the effects of scalar fields on cosmological and black hole solutions. By comparison, an analysis of an inhomogeneous cosmological model which requires no extensions to general relativity is also undertaken. In chapter three, examples of numerical solutions to black hole solutions, which have previously been shown to be linearly stable, are found. The model includes at least two scalar fields, non-minimally coupled to electromagnetism and hence possesses non-trivial contingent primary hair. We show that the extremal solutions have finite temperature for an arbitrary coupling constant. Chapter four investigates the effects of higher order curvature corrections and scalar fields on the late-time cosmological evolution. We find solutions which mimic many of the phenomenological features seen in the post-inflation Universe. The effects due to non-minimal scalar couplings to matter are also shown to be negligible in this context. Such solutions can be shown to be stable under homogeneous perturbations. Some restrictions on the value of the slope of the scalar coupling to the Gauss-Bonnet term are found to be necessary to avoid late-time superluminal behaviour and dominant energy condition violation. A number of observational tests are carried out in chapter five on a new approach to averaging the inhomogeneous Universe. In this "Fractal Bubble model" cosmic acceleration is realised as an apparent effect, due to quasilocal gravitational energy gradients. We show that a good fit can be found to three separate observations, the type Ia supernovae, the baryon acoustic oscillation scale and the angular scale of the sound horizon at last scattering. The best fit to the supernovae data is χ² ≃ 0:9 per degree of freedom, with a Hubble parameter at the present epoch of H0 = 61:7+1:4 -1:3 km sec⁻¹ Mpc⁻¹ , and a present epoch volume void fraction of 0:76 ± 0:05.

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This thesis combines the gravity model with Dunning’s four motivations and three control variables for Chinese outward Foreign Direct Investment (OFDI), and provides an empirical country level analysis on the determinants of Chinese OFDI in 34 OECD countries from 2003 to 2010. I find that resource-seeking motivation is a determinant of Chinese OFDI; the market-seeking motive is shown insignificant influence on Chinese OFDI; the strategic asset-seeking motivation of Chinese OFDI is not supported due to its unexpected negative sign. Moreover, the efficiency seeking motivation was not considered in previous studies due to low labor cost in China. In this thesis, by using real labor cost as a proxy, I prove that Chinese OFDI is not driven by efficiency seeking motive.

In the year of 1999 a new monetary experiment commenced – the birth of the euro. Over the years more countries have joined the new currency and it was expected to be a continuously growing community. The purpose of this paper is to measure the effect of European membership, the currency of euro and the financial crisis on trade between the countries located in Europe. For the task of this paper the gravity model is used to study the bilateral trade flows in the European Union from 1995-2011. It additionally investigates, besides the correlation between GDP and distance, the effect of shared border, shared language and coastal access. The results showed that the euro did indeed have a positive impact on trade in the introduction year to later significantly have a negative impact on trade. Moreover, a membership in the European Union results showed to promote intra-European Union trade at the cost of extra-European Union trade and have its largest impact in the beginning and end of the study years. The conclusion is that other factors than increased trade were the main reasons to join the European Union, such as enhancing the role of Europe in the world market and to turn into a unified market. Finally, the effect of the financial crisis was found to have a negative impact on trade, concluded that it exposed the failures and lack of coordination between and within countries. It was also shown that the physical distance, and not specifically distances in i.e. social culture and languages, boosted the trade between countries.

In this thesis we review and build on the common methods used to analyze null geodesics in Schwarzschild de Sitter space. We present a general technique which allows finding measurable intersection angles of null trajectories analytically, and as one of its applications we establish a general relativistic aberration relationship. The tools presented are used to analyze some standard setups of gravitational deflection of light and gain a clear understanding of the role that the cosmological constant, Λ, plays in gravitational lensing phenomena. Through reviewing some recent papers on the topic with the present results in mind, we attempt to explain the major sources of disagreement in the ongoing debate on the subject, which started with Rindler and Ishak’s original paper, regarding the influence of Λ on lensing phenomena. To avoid ambiguities and room for misunderstanding we present clear definitions of the quantities used in the present analysis as well as in other papers we discuss. / Thesis (Master, Physics, Engineering Physics and Astronomy) -- Queen's University, 2013-09-30 21:18:26.762

This paper considers alternative methods to estimate econometric models based on bilateral data when only aggregate information on the dependent variable is available. Such methods can be used to obtain an indication of the sign and magnitude of bilateral model parameters and, more importantly, to decompose aggregate into bilateral data, which can then be used as proxy variables in further empirical analysis. We perform a Monte Carlo study and carry out a simple real world application using intra-EU trade and capital flows, showing that the methods considered work reasonably well and are worthwhile being considered in the absence of bilateral data. (authors' abstract) / Series: Department of Economics Working Paper Series

Nonlinearity in oscillations and waves can lead to dramatic and useful behavior. The course PH4459 at the Naval Postgraduate School was recently redesigned to extend its original subject of nonlinear acoustics to nonlinear oscillations and waves in general, with minimal prerequisites so that non-acoustics-tracked students can enroll in the course. Due to the unusual behavior and mathematical difficulty of nonlinear systems, lecture demonstrations are vital to the teaching of the course. The purpose of this thesis is to develop two new demonstrations for the course, and to improve an existing demonstration. In one of the new demonstrations, we investigate the generation and detection of high-amplitude waves on water to demonstrate the dependence of the wave speed upon amplitude. The experimental data agree with the theory. In the other new demonstration, we investigate a compression driver that exhibits a strong response at half the frequency of the drive. Data and the current scientific literature indicate that this behavior is due to parametric excitation of the deformation modes of the diaphragm assembly. Finally, we describe improvements to a torsional oscillator that is parametrically excited by modulation of its length. The improvements include a new motor, sturdier construction, and a new torsional strip.

Northern Sweden is one of the largest hosts for mineral resources in Europe and always has been an interesting area for researchers from various disciplines of Earth sciences. This dissertation is a comprehensive summary of three case study papers on airborne VLF, gravity gradient and magnetic data in the area. In the first paper, tensor VLF data is extracted from an old data set which contains only the total and the vertical magnetic components. The anomalous part of the horizontal magnetic field components is computed by a Hilbert transform of the vertical magnetic field. The normal part of the horizontal magnetic field component is computed as a function of total, vertical and anomalous part of horizontal magnetic fields. The electric field is also calculated for TE mode and impedance tensor and apparent resistivity are computed. In addition tippers are calculated for two transmitters and inverted by a 3D inversion algorithm. Comparison of the estimated model and geology map of bedrock shows that lower resistivity zones are correlated with mineralizations. The second paper deals with the internal consistency of airborne gravity gradient data. The six components of the data are estimated from a common potential function. It is shown that the data is adequately consistent but at shorter land clearances the difference between the estimated data and the original data is larger. The technique is also used for computing the Bouguer anomaly from terrain corrected FTG data. Finally the data is inverted in 3D, which shows that the estimated density model in shallow depth is dominated by short wave length features. Inversion of TMI data is the topic of the third paper where a new type of reference model for 3D inversion of magnetic data is proposed by vertically extending the estimated magnetization of a 2D terrain magnetization model. The final estimated 3D result is compared with the magnetization model where no reference model is used. The comparison shows that using the reference model helps the high magnetization zones in the estimated model at shallow depths to be better correlated with measured high remanent magnetization from rock samples. The high magnetization zones are also correlated with gabbros and volcanic metasediments.