793 research outputs found
Effective field theory analysis of the self-interacting chameleon
No full textWe analyse the phenomenology of a self-interacting scalar field in the context of the chameleon scenario originally proposed by Khoury and Weltman. In the absence of self-interactions, this type of scalar field can mediate long range interactions and simultaneously evade constraints from violation of the weak equivalence principle. By applying to such a scalar field the effective field theory method proposed for Einstein gravity by Goldberger and Rothstein, we give a thorough perturbative evaluation of the importance of non-derivative self-interactions in determining the strength of the chameleon mediated force in the case of orbital motion. The self-interactions are potentially dangerous as they can change the long range behaviour of the field. Nevertheless, we show that they do not lead to any dramatic phenomenological consequence with respect to the linear case and solar system constraints are fulfilled
Extracting the three- and four-graviton vertices from binary pulsars and coalescing binaries
No full textUsing a formulation of the post-Newtonian expansion in terms of Feynman graphs, we discuss how various tests of general relativity (GR) can be translated into measurement of the three- and four-graviton vertices. In problems involving only the conservative dynamics of a system, a deviation of the three-graviton vertex from the GR prediction is equivalent, to lowest order, to the introduction of the parameter βPPN in the parametrized post-Newtonian formalism, and its strongest bound comes from lunar laser ranging, which measures it at the 0.02% level. Deviation of the three-graviton vertex from the GR prediction, however, also affects the radiative sector of the theory. We show that the timing of the Hulse-Taylor binary pulsar provides a bound on the deviation of the three-graviton vertex from the GR prediction at the 0.1% level. For coalescing binaries at interferometers we find that, because of degeneracies with other parameters in the template such as mass and spin, the effects of modified three- and four-graviton vertices is just to induce an error in the determination of these parameters and, at least in the restricted PN approximation, it is not possible to use coalescing binaries for constraining deviations of the vertices from the GR predictio
Graphic Novels: Let's Hear From You!
No full textFormer URI: http://hdl.handle.net/10125/59386Public libraries are an important part of our society and provide a sanctuary for all seeking knowledge and comfort. Graphic novels have become a rising trend within public libraries, however at times it can be difficult to place them. Check out this session about graphic novels by two librarians who are just crazy about them! Bring your questions, get opinions from Hillary and Kelly regarding the latest trends and how it can help your graphic novel collections succeed. We are gonna hear from you on your thoughts and questions and hopefully you leave satisfied and knowing how to work with this insanely popular literary medium
OLMASA : Olotayan Marine Sanctuary
No full textv, 73 p.The author worked with the Olotayan Marine Sanctuary Foundation to improve the environmental and economic health of the small Philippine island of Olotayan
Sanctuary Gardens: Roots - Words - Meaning
No full textThe author writes about her work in creating secular sanctuary gardens in both literal and allegorical forms
On Testing Modified Gravity : with Solar System Experiments and Gravitational Radiation
No full textThree theories of gravitation – general relativity, the chameleon and Horava gravity - are confronted with experiment, using standard and adapted post-Newtonian (PN) tools. The laboratory is provided by the Solar System, binary pulsars and future detections at gravitational wave observatories. We test Horava gravity by studying emission of gravitational radiation in the weak-field limit for PN sources using techniques that take full advantage of the parametrized post-Newtonian (PPN) formalism. In particular, we provide a generalization of Einstein's quadrupole formula and show that a monopole persists even in the limit in which the PPN parameters are identical to those of General Relativity. Based on a technique called non-relativistic General Relativity, we propose a phenomenological way to measure deviations from General Relativity coming from an unknown UV completion. Finally, we systematically show that the self-interacting chameleon at orders three and higher do not jeopardize the chameleon theory for Solar System type objects
S4 E1 Raiding Sanctuary
No full textWhen anti-immigration raids intensified in the USA after Trump’s return to the presidency, it left many wondering: how could this happen in places like LA, ostensibly a “Sanctuary City”? What, in fact, are sanctuary cities? Launching our new series on the role of borders and migration in the roll out of Donald Trump’s MAGA project, Rachel Humphris, author of “Making Sanctuary Cities” joins us to explain all. She outlines the rich history of such places, with roots in both traditions of sheltering refugees but also in activist histories of non-cooperation. Rachel also describes how the term ‘Sanctuary Cities’ was appropriated in the so-called ‘culture wars’, used by the right to paint a misleading picture of urban areas as full of “undesirable” outsiders and their apparently woke defenders. Plus, we ask: what does the label ‘Sanctuary City’ obscure in places such as San Francisco, where many are being forced out as big tech money floods in? And how, by focusing on the history of American cities’ complex and caveated relationship to the federal state, might we still hold to a future of hope and resistance
Towards the Cathedral: Ancient Sanctuary Represented in the American Context
No full textIn this Article, Mr. Feeley, discusses the historical roots of the power of the Church to provide sanctuary to those in fear of life and limb. Tracing its historical roots, the author identifies three elements of sanctuary - person, place, governmental check. He then demonstrates that the American Sanctuary Movement contains these defining elements of historical sanctuary. An analysis of the Sanctuary Movement concludes that, despite its different features and cultural locus, the Movement embodies the ancient elements of person, place and governmental check transformed, rather than transubstantiated by the American context
A Field Guide to Sanctuary: Women’s Experiences of Personal Sanctuary Contextualised Within Chronic Health Conditions
No full textThis analytic autoethnography draws on a passage from Celtic philosopher John O’Donohue to consider women’s experience of personal sanctuary within the context of chronic health conditions. Guided by the question: ‘what is your experience of sanctuary and how does that relate to your experience of your chronic health condition’ and informed heavily by social work theory and practice, this dissertation engages a range of research methodologies and methods, including Critical Reflection on Practice and Response Art (from art therapy) in conjunction with participant interviews. Through the constant comparative method, the data revealed that within this context, sanctuary comprises elements (spirituality, nature, creativity, and purposeful occupation), as well as qualities (transgressiveness, nourishingness, and fluidity). This research not only revealed the structure of sanctuary, it assisted the author to understand sanctuary as her personal ministry and fundamental to her social work practice, as well as clarifying the spiritual practices leading to her experience of sanctuary. This dissertation concludes with many plans for future study, including the possibility of this type of sanctuary as a social work practice framework
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