Pseudoscalar N-flation and axial coupling revisited

We revisit the dynamics of the axial coupling between many N-flatons and an Abelian gauge field, with special attention to its statistically anisotropic signal. The anisotropic power spectrum of curvature perturbations associated to the large wavelength modes of the gauge vector field is generally undetectable, since the anisotropy is confined to small scales. If the gauge field is the electromagnetic field, provided that the number of fields participating in the exponential expansion is large, it could be possible to generate sizable large scale magnetic fields. However, its spectrum is blue, and appreciable power on large scales implies an overly strong field on smaller scales, incompatibly with observations. Furthermore, the anisotropy is also markedly enhanced, and might be at odds with the isotropic observed sky. These aspects further demand that the scale of inflation is kept to a minimum.Comment: 14 pages - v2 with minor changes in the conclusions, v3 to match published versio

California FreshWorks Food Access Report: An Examination of Three Northgate Gonzalez Grocery Store Investments

In order to better understand and maximize FreshWorks' impact, The California Endowment commissioned a two-year evaluation of the program's food access, social, and economic outcomes. The evaluation focused on the impact of three FreshWorks investments made with the purpose of increasing access to healthy food. The evaluation examined three new Northgate González Markets which received New Markets Tax Credit financing through FreshWorks.To understand the influence of FreshWorks on increasing access to healthy food and changing food purchase and consumption patterns in underserved communities, the evaluation team examined two key questions: 1. Are the new retail food stores meeting unmet need for grocery services? 2. How do community members perceive the benefits and/or negative consequences of the new stores

Parallel Narrative: Short-Video Social Media Platforms’ Influences on Contemporary Narrative

Through the study of Kwai, a popular short-video social media platform in China, this thesis investigates the social issues, media class divides and aesthetics specific to Kwai culture. It further proposes a strategy of artistic practice - parallel narrative - an experiment in video art production and editing techniques that explores new possibilities of narrative in video art. Integrating theoretical research on Post-Internet art and object-oriented ontology, this thesis reveals people’s ability to digest multisource information and shows how mobile technologies and open-source materials contribute to the formation of parallel narratives

Period of shame - The effects of menstrual hygiene management on rural women and girls' quality of life in Savannakhet, Laos

The purpose of this thesis was to investigate how rural women and girls’ menstrual hygiene management (MHM) affects their life-quality and performance in everyday life. The thesis analysed the opportunities, abilities and motivation they had in performing MHM and how it affected their social and economical opportunities. From this, conclusions were drawn on how MHM affects their life-quality. A concurrent mixed methods approach was implemented where qualitative data was gathered through group interviews and quantitative data through closed questionnaires. The results were analysed through a combination of the FOAM-framework and Sen’s capabilities approach. The results showed that not all women had sufficient access to toilets, water, panties and sanitary pads. Together with an absence in social support and cultural norms that perceive menstruation as taboo, these factors had negative consequences on their life-quality. It restricted them in their access to a good health, education and income-generating activities. The effects are however subjective; not all women saw their practice as problematic. The results merely showed that not all women had access in exercising their capabilities, which could lead to a decreased level of life-quality. Individuals as well as societies could thus benefit in taking MHM into consideration in the development discourse

The Critical Role of Statistics in Demostrating the Reliability of Expert Evidence

Federal Rule of Evidence 702, which covers testimony by expert witnesses, allows a witness to testify “in the form of an opinion or otherwise” if “the testimony is based on sufficient facts or data” and “is the product of reliable principles and methods” that have been “reliably applied.” The determination of “sufficient” (facts or data) and whether the “reliable principles and methods” relate to the scientific question at hand involve more discrimination than the current Rule 702 may suggest. Using examples from latent fingerprint matching and trace evidence (bullet lead and glass), I offer some criteria that scientists often consider in assessing the “trustworthiness” of evidence to enable courts to better distinguish between “trustworthy” and “questionable” evidence. The codification of such criteria may ultimately strengthen the current Rule 702 so courts can better distinguish between demonstrably scientific sufficiency and “opinion” based on inadequate (or inappurtenant) methods

Predator empire: the geopolitics of U.S. drone warfare

This paper critically assesses the CIA’s drone program and proposes that the use of unmanned aerial vehicles is driving an increasingly paramilitarized U.S. national security strategy. The paper suggests that large-scale ground wars are being eclipsed by fleets of weaponized drones capable of targeted killings across the planet. Evidence for this shift is found in key security documents that mobilize an amorphous war against vaguely defined al-Qa’ida “affiliates”. This is further legitimized by the White House’s presentation of drone warfare as a bureaucratic task managed by a “disposition matrix”. Such abstract narratives are challenged through the voices of people living in the tribal areas of Pakistan. What I call the Predator Empire names the biopolitical power that catalogues and eliminates threatening “patterns of life”. This permanent war is enabled by a topological spatial power that folds the environments of the “affiliate” into the surveillance machinery of the Homeland

Polynomial-Time Algorithms for Quadratic Isomorphism of Polynomials: The Regular Case

Let $\mathbf{f}=(f\_1,\ldots,f\_m)$ and $\mathbf{g}=(g\_1,\ldots,g\_m)$ be two sets of $m\geq 1$ nonlinear polynomials over $\mathbb{K}[x\_1,\ldots,x\_n]$ ($\mathbb{K}$ being a field). We consider the computational problem of finding -- if any -- an invertible transformation on the variables mapping $\mathbf{f}$ to $\mathbf{g}$. The corresponding equivalence problem is known as {\tt Isomorphism of Polynomials with one Secret} ({\tt IP1S}) and is a fundamental problem in multivariate cryptography. The main result is a randomized polynomial-time algorithm for solving {\tt IP1S} for quadratic instances, a particular case of importance in cryptography and somewhat justifying {\it a posteriori} the fact that {\it Graph Isomorphism} reduces to only cubic instances of {\tt IP1S} (Agrawal and Saxena). To this end, we show that {\tt IP1S} for quadratic polynomials can be reduced to a variant of the classical module isomorphism problem in representation theory, which involves to test the orthogonal simultaneous conjugacy of symmetric matrices. We show that we can essentially {\it linearize} the problem by reducing quadratic-{\tt IP1S} to test the orthogonal simultaneous similarity of symmetric matrices; this latter problem was shown by Chistov, Ivanyos and Karpinski to be equivalent to finding an invertible matrix in the linear space $\mathbb{K}^{n \times n}$ of $n \times n$ matrices over $\mathbb{K}$ and to compute the square root in a matrix algebra. While computing square roots of matrices can be done efficiently using numerical methods, it seems difficult to control the bit complexity of such methods. However, we present exact and polynomial-time algorithms for computing the square root in $\mathbb{K}^{n \times n}$ for various fields (including finite fields). We then consider \\#{\tt IP1S}, the counting version of {\tt IP1S} for quadratic instances. In particular, we provide a (complete) characterization of the automorphism group of homogeneous quadratic polynomials. Finally, we also consider the more general {\it Isomorphism of Polynomials} ({\tt IP}) problem where we allow an invertible linear transformation on the variables \emph{and} on the set of polynomials. A randomized polynomial-time algorithm for solving {\tt IP} when $\mathbf{f}=(x\_1^d,\ldots,x\_n^d)$ is presented. From an algorithmic point of view, the problem boils down to factoring the determinant of a linear matrix (\emph{i.e.}\ a matrix whose components are linear polynomials). This extends to {\tt IP} a result of Kayal obtained for {\tt PolyProj}.Comment: Published in Journal of Complexity, Elsevier, 2015, pp.3