Optimal estimation of time-dependent gravitational fields with quantum optomechanical systems

We study the fundamental sensitivity that can be achieved with an ideal optomechanical system in the nonlinear regime for measurements of time-dependent gravitational fields. Using recently developed methods to solve the dynamics of a nonlinear optomechanical system with a time-dependent Hamiltonian, we compute the quantum Fisher information for linear displacements of the mechanical element due to gravity. We demonstrate that the sensitivity can not only be further enhanced by injecting squeezed states of the cavity field, but also by modulating the light--matter coupling of the optomechanical system. We specifically apply our results to the measurement of gravitational fields from small oscillating masses, where we show that, in principle, the gravitational field of an oscillating nano-gram mass can be detected based on experimental parameters that will likely be accessible in the near-term future. Finally, we identify the experimental parameter regime necessary for gravitational wave detection with a quantum optomechanical sensor

Ethics and the crimes of the powerful

The ethical dimension adds a key tool for the analysis of the crimes of the powerful. This dimension is introduced in the analysis of the present article, which seeks to establish how offenders endowed with resources and power justify their conduct through a selective interpretation of classical Western philosophy

Gut thinking: the gut microbiome and mental health beyond the head

Background: In recent decades, dominant models of mental illness have become increasingly focused on the head, with mental disorders being figured as brain disorders. However, research into the active role that the microbiome-gut-brain axis plays in affecting mood and behaviour may lead to the conclusion that mental health is more than an internalised problem of individual brains. Objective: This article explores the implications of shifting understandings about mental health that have come about through research into links between the gut microbiome and mental health problems such as depression and anxiety. It aims to analyse the different ways that the lines between mind and body and mental and physical health are re-shaped by this research, which is starting to inform clinical and public understanding. Design: As mental health has become a pressing issue of political and public concern it has become increasingly constructed in socio-cultural and personal terms beyond clinical spaces, requiring a conceptual response that exceeds biomedical inquiry. This article argues that an interdisciplinary critical medical humanities approach is well positioned to analyse the impact of microbiome-gut-brain research on conceptions of mind. Results: The entanglement of mind and matter evinced by microbiome-gut-brain axis research potentially provides a different way to conceptualise the physical and social concomitants of mental distress. Conclusion: Mental health is not narrowly located in the head but is assimilated by the physical body and intermingled with the natural world, requiring different methods of research to unfold the meanings and implications of gut thinking for conceptions of human selfhood

Krisis as the scene of non-decisional judgement: A performance-fiction for the generic human

François Laruelle’s non-standard aesthetics proposes a framework for ‘conjugating’ philosophy with the arts to articulate new models of thought (2012a). This posture of thinking is posed as a defence of man against the presuppositions that ground philosophy, which conceptually overdetermine the human and condemn thought to a perpetual state of crisis (Gracieuse et al. 2012). Laruelle’s epistemological approach holds a certain potential for the field of performance philosophy because it brings performance together with philosophy in a non-hierarchical arrangement that combines their respective means, producing an ‘art of thought’ (Laruelle 2012a, 5). This article examines the effects of bringing performance into thought in this manner, by putting Laruelle’s pragmatics into practice. It enacts a non-standard re-description of two sets of theoretical materials: one ‘philosophical’, the other from ‘performance theory’. The first, a deconstruction of the performativity of human rights declarations (Hamacher 2006), resonates with Laruelle’s concerns about the conceptual overdetermination of the human; however, it appeals to the Platonic scene of krisis as an alternative paradigm for presenting the human—which remains an event with a crisis-structure. The second, an aesthetic theory of performance conceived as a liminal event (Fischer-Lichte 2008), has a similar structure. By articulating these materials together, I will show how terms can be extracted from performance theory and used as a means to radicalise the scene of krisis, producing a stage on which the ‘human’ can be presented in an underdetermined mode. This allows us to achieve a non-predicative theorisation of the human that eludes Hamacher, whilst demonstrating through practice the abstract procedure by which ‘performance’ is utilised in the context of non-standard aesthetics

Facts, Values and Quanta

Quantum mechanics is a fundamentally probabilistic theory (at least so far as the empirical predictions are concerned). It follows that, if one wants to properly understand quantum mechanics, it is essential to clearly understand the meaning of probability statements. The interpretation of probability has excited nearly as much philosophical controversy as the interpretation of quantum mechanics. 20th century physicists have mostly adopted a frequentist conception. In this paper it is argued that we ought, instead, to adopt a logical or Bayesian conception. The paper includes a comparison of the orthodox and Bayesian theories of statistical inference. It concludes with a few remarks concerning the implications for the concept of physical reality.Comment: 30 pages, AMS Late

No Pixel Left Behind: Interactively Visualizing ''Everything'' from NASA's Earth Observations

The problem: satellite swath overlaps. Polar orbiting satellites like Terra, Aqua, and the joint NASA/NOAA Suomi-NPP satellite circle the globe from pole to pole, collecting data daily, swath by swath. Having this density of data is great for building a comprehensive mosaic of the planet, but sometimes there is something interesting occurring in one swath but is covered by a subsequent swath when the satellite passes over 90 minutes later. With our new prototype based on Worldview and the Global Imagery Browse Services (GIBS), we combine the best of both worlds to interactively visualize the entire globe as a mosaic and allow the user to _peel away the overlaps_ to see every pixel that was observed by the satellite. This ability to look at every pixel - and to know when they were captured - is especially important near the poles where swath overlaps are most common

Reciprocity as a foundation of financial economics

This paper argues that the subsistence of the fundamental theorem of contemporary financial mathematics is the ethical concept ‘reciprocity’. The argument is based on identifying an equivalence between the contemporary, and ostensibly ‘value neutral’, Fundamental Theory of Asset Pricing with theories of mathematical probability that emerged in the seventeenth century in the context of the ethical assessment of commercial contracts in a framework of Aristotelian ethics. This observation, the main claim of the paper, is justified on the basis of results from the Ultimatum Game and is analysed within a framework of Pragmatic philosophy. The analysis leads to the explanatory hypothesis that markets are centres of communicative action with reciprocity as a rule of discourse. The purpose of the paper is to reorientate financial economics to emphasise the objectives of cooperation and social cohesion and to this end, we offer specific policy advice