8 research outputs found
Constraining the Nature of Dark Energy using the SKA
We investigate the potential of the Square Kilometer Array Telescope (SKA) to
constrain the sound speed of dark energy. The Integrated Sachs Wolfe (ISW)
effect results in a significant power spectrum signal when CMB temperature
anisotropies are cross-correlated with galaxies detectable with the SKA in HI.
We consider using this measurement, the autocorrelation of HI galaxies and the
CMB temperature power spectrum to derive constraints on the sound speed. We
study the contributions to the cross-correlation signal made by galaxies at
different redshifts and use redshift tomography to improve the signal-to-noise.
We use a chi-square analysis to estimate the significance of detecting a sound
speed different from that expected in quintessence models, finding that there
is potential to distinguish very low sound speeds from the quintessence value.Comment: 8 pages, 8 figures; updated references for publication MNRA
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Finance, energy and the decoupling: an empirical study
This paper investigates the empirical and theoretical basis of the decoupling between energy throughput and economic growth, with a critical view of the use of the decoupling concept as a policy priority. We provide an analysis of the historical trends of the metabolic pattern of European economies over a period of 18 years focusing on the changes in energy throughput and financial assets. The results show that energy consumption per hour of labor has remained constant, suggesting that no significant changes in production processes or technology have taken place in the productive sectors of the economy. The contribution of this paper is to establish a bridge between the economic analysis of financialization and the societal metabolism analysis of the economic process from a biophysical point of view. We argue that this bridge is crucial to draw attention to the biophysical consequences of financialization (a relative decoupling) and critically assess the pertinence of policies aimed at encouraging the decoupling in the context of increasing inequality