Multigrid Methods in Lattice Field Computations

The multigrid methodology is reviewed. By integrating numerical processes at all scales of a problem, it seeks to perform various computational tasks at a cost that rises as slowly as possible as a function of $n$, the number of degrees of freedom in the problem. Current and potential benefits for lattice field computations are outlined. They include: $O(n)$ solution of Dirac equations; just $O(1)$ operations in updating the solution (upon any local change of data, including the gauge field); similar efficiency in gauge fixing and updating; $O(1)$ operations in updating the inverse matrix and in calculating the change in the logarithm of its determinant; $O(n)$ operations per producing each independent configuration in statistical simulations (eliminating CSD), and, more important, effectively just $O(1)$ operations per each independent measurement (eliminating the volume factor as well). These potential capabilities have been demonstrated on simple model problems. Extensions to real life are explored.Comment: 4

From abstract art to abstracted artists

What lineage connects early abstract films and machine-generated YouTube videos? Hans Richter’s famous piece Rhythmus 21 is considered to be the first abstract film in the experimental tradition. The Webdriver Torso YouTube channel is composed of hundreds of thousands of machine-generated test patterns designed to check frequency signals on YouTube. This article discusses geometric abstraction vis-à-vis new vision, conceptual art and algorithmic art. It argues that the Webdriver Torso is an artistic marvel indicative of a form we call mathematical abstraction, which is art performed by computers and, quite possibly, for computers

Rapid HIV testing program implementation: lessons from the emergency department

Background: The US Centers for Disease Control and Prevention (CDC) guidelines and the World Health Organization (WHO) both recommend HIV testing in health-care settings. However, neither organization provides prescriptive details regarding how these recommendations should be adapted into clinical practice in an emergency department. Methods: We have implemented an HIV-testing program in the ED of a major academic medical center within the scope of the Universal Screening for HIV Infection in the Emergency Room (USHER) Trial—a randomized clinical trial evaluating the feasibility and cost-effectiveness of HIV screening in this setting. Results and conclusion: Drawing on our collective experiences in establishing programs domestically and internationally, we offer a practical framework of lessons learned so that others poised to embark on such HIV testing programs may benefit from our experiences

Photography and Trauma in Photo-fiction: Literary Montage in the Writings of Jonathan Safran Foer, Aleksandar Hemon and W. G. Sebald

Located on the interstice between Media Studies and Literary Theory, my dissertation explores the emerging genre of photo-fiction -- literary works that incorporate photographic images into the manuscripts -- and its impact on the commemoration of traumatic historical events. I argue that the way we represent and remember historical traumas is dependent on the media in which images emanating from these events are produced and circulated; put differently, the context of these images shapes our engagement with them. By examining literary works that incorporate photographs into their printed text, I explore textual and visual representations of historical trauma (such as the two World Wars, the Balkan wars of the Nineties, and 9/11). The authors whose works I analyze (Jonathan Safran Foer, Aleksandar Hemon, W.G. Sebald) grant photography a new status: the inserted images transcend traditional “authentification strategies” and draw attention to the convergence of realism and indexicality featured by these photographs. These authors’ employment of photographs from various media (television, internet, printed press, encyclopedias and archives) questions not only the technical qualities of each medium but the veracity and accuracy of evidence. Photography’s capacity to secure and store information is put radically into question, not only because the new contexts of these images, but because of the manipulations and reconfigurations the movement between media has brought about. Drawing on Walter Benjamin’s concept of the literary montage, I suggest that literature provides an apt arena to examine the reception to images. By literary montage I mean the opening up of a new dimension in which visual and verbal elements are juxtaposed, and the disjunctions and gaps between them encourage readers to become active participants in the creation of narrative. Photo-fiction’s interplay between images and texts therefore not only sheds light on the mechanics of representation, but demand from its audience to reflect on the way we interpret and respond to historical traumas in a society saturated with images.Ph