Effective action approach to cosmological perturbations in dark energy and modified gravity

In light of upcoming observations modelling perturbations in dark energy and modified gravity models has become an important topic of research. We develop an effective action to construct the components of the perturbed dark energy momentum tensor which appears in the perturbed generalized gravitational field equations, {\delta}G_{\mu\nu} = 8{\pi}G{\delta}T_{\mu\nu} + {\delta}U_{\mu\nu} for linearized perturbations. Our method does not require knowledge of the Lagrangian density of the dark sector to be provided, only its field content. The method is based on the fact that it is only necessary to specify the perturbed Lagrangian to quadratic order and couples this with the assumption of global statistical isotropy of spatial sections to show that the model can be specified completely in terms of a finite number of background dependent functions. We present our formalism in a coordinate independent fashion and provide explicit formulae for the perturbed conservation equation and the components of {\delta}U_{\mu\nu} for two explicit generic examples: (i) the dark sector does not contain extra fields, L = L(g_{\mu\nu}) and (ii) the dark sector contains a scalar field and its first derivative L = L(g_{\mu\nu}, {\phi}, \nabla_{\mu}{\phi}). We discuss how the formalism can be applied to modified gravity models containing derivatives of the metric, curvature tensors, higher derivatives of the scalar fields and vector fields.Comment: Version accepted by JCAP. Typos corrected. Covariant decoupling conditions adde

Archaeology of the Ryukyu Islands: A Regional Chronology from 3000 B.C. to the Historic Period

Humanities Open Book Program, a joint initiative of the National Endowment for the Humanities and the Andrew W. Mellon FoundationArchaeological excavations have produced findings showing many important relationships between the culture of the Ryukyu Islands and that of surrounding areas, especially the islands of Kyushu and Taiwan. The present study is a synthesis of findings from excavations in Kyushu and the Ryukyus, particularly those contributed by Japanese researchers published in the last decade and those resulting from recent fieldwork on the east coast of Taiwan. From his own excavations .and those of other archaeologists, the author has formulated phases of cultural development and has related them in a regional temporal framework. Included here is an extensive, detailed analysis of ceramic typology for southern Kyushu and proposed ceramic types and wares for the Ryukyus and Taiwan. The author suggests that cultural differences between Kyushu and the Ryukyus may have resulted from the isolation of small colonizing groups and through the interaction of the inhabitants with differing environments. An important contribution to the literature on Far Eastern prehistory, this book also places Ryukyuan culture in the context of related neighboring cultures, and it should be of interest to anyone concerned with East Asian cultural history

Flesh on the Bones: Animal Bodies in Atlantic Roundhouses

This volume presents the state of research across Europe to illustrate how comparable interpretative frameworks are used by archaeologists working with both prehistoric and historical societies

Psychological investigations for adults with type 1 diabetes

This portfolio thesis consists of three parts: a systematic literature review, an empirical report and appendices including a reflective statement.Part one is a systematic literature review investigating the impact psychological interventions have on aiding glycaemic control in adults with type 1 diabetes. This review systematically searched 6 databases to find 10 randomised control trials which met the requirements of the inclusion and exclusion criteria. A meta-analysis was employed to assess whether glycaemic control improved in the group using psychological interventions compared to individuals receiving usual diabetes care. The results of the investigation are reported along with limitations to the review, and a discussion of study quality and clinical implications.Part two is an empirical paper which reports the findings of an investigation into objective memory functioning, subjective memory, and differences between objective memory and subjective memory in adults with type 1 diabetes. Objective memory was measured using the BMIPB, whilst subjective memory was assessed using the Memory Functioning Questionnaire. Potential covariates were measured, which included mood, anxiety and information processing speed, to investigate whether they influenced any potential differences between objective and subjective memory. There were three groups of participants used, which were people with poorly-controlled diabetes, people with well-controlled diabetes, and a healthy control group. The results from the study, along with a discussion of clinical implications have been reported.Part three is comprised of the appendices of supporting information from the empirical paper and systematic literature review, as well as a reflective statement