Gravitational Lensing by Spinning Black Holes in Astrophysics, and in the Movie Interstellar

Interstellar is the first Hollywood movie to attempt depicting a black hole as it would actually be seen by somebody nearby. For this we developed a code called DNGR (Double Negative Gravitational Renderer) to solve the equations for ray-bundle (light-beam) propagation through the curved spacetime of a spinning (Kerr) black hole, and to render IMAX-quality, rapidly changing images. Our ray-bundle techniques were crucial for achieving IMAX-quality smoothness without flickering. This paper has four purposes: (i) To describe DNGR for physicists and CGI practitioners . (ii) To present the equations we use, when the camera is in arbitrary motion at an arbitrary location near a Kerr black hole, for mapping light sources to camera images via elliptical ray bundles. (iii) To describe new insights, from DNGR, into gravitational lensing when the camera is near the spinning black hole, rather than far away as in almost all prior studies. (iv) To describe how the images of the black hole Gargantua and its accretion disk, in the movie \emph{Interstellar}, were generated with DNGR. There are no new astrophysical insights in this accretion-disk section of the paper, but disk novices may find it pedagogically interesting, and movie buffs may find its discussions of Interstellar interesting.Comment: 46 pages, 17 figure

Visualizing Interstellar's Wormhole

Christopher Nolan's science fiction movie Interstellar offers a variety of opportunities for students in elementary courses on general relativity theory. This paper describes such opportunities, including: (i) At the motivational level, the manner in which elementary relativity concepts underlie the wormhole visualizations seen in the movie. (ii) At the briefest computational level, instructive calculations with simple but intriguing wormhole metrics, including, e.g., constructing embedding diagrams for the three-parameter wormhole that was used by our visual effects team and Christopher Nolan in scoping out possible wormhole geometries for the movie. (iii) Combining the proper reference frame of a camera with solutions of the geodesic equation, to construct a light-ray-tracing map backward in time from a camera's local sky to a wormhole's two celestial spheres. (iv) Implementing this map, for example in Mathematica, Maple or Matlab, and using that implementation to construct images of what a camera sees when near or inside a wormhole. (v) With the student's implementation, exploring how the wormhole's three parameters influence what the camera sees---which is precisely how Christopher Nolan, using our implementation, chose the parameters for \emph{Interstellar}'s wormhole. (vi) Using the student's implementation, exploring the wormhole's Einstein ring, and particularly the peculiar motions of star images near the ring; and exploring what it looks like to travel through a wormhole.Comment: 14 pages and 13 figures. In press at American Journal of Physics. Minor revisions; primarily insertion of a new, long reference 15 at the end of Section II.

Eugenie S. Kleinerman, MD

https://openworks.mdanderson.org/legendsandlegacieschapters/1009/thumbnail.jp

10: Eugenie S. Kleinerman, MD

https://openworks.mdanderson.org/legendsandlegaciesbook/1012/thumbnail.jp

Tumor Vessel Development and Expansion in Ewing's Sarcoma: A Review of the Vasculogenesis Process and Clinical Trials with Vascular-Targeting Agents

Ewing's sarcoma accounts for a disproportionately high portion of the overall pediatric mortality rate compared to its rare incidence in the pediatric population. Little progress has been made since the introduction of traditional chemotherapies, and understanding the biology of the tumor is critical for developing new therapies. Ewing's sarcomas rely on a functional vascular supply, which is formed by a combination of angiogenesis and vasculogenesis. Recent insights into the molecular regulation of bone marrow (BM) cell participation in vascular development have identified VEGF, SDF-1α, and DLL4 as critical players in the vasculogenesis process. Clinical trials using vascular targeting agents, specifically targeting VEGF or DLL4, are underway

Educational Administration and Leadership Curricula for Modern Nation-Building in Muslim Countries: Modernisation, National Identity and the Preservation of Values and Culture

Despite the dominance of neoliberal ideology aimed at economic advancement, two of the main purposes of educational systems still is the cultivation of national identity and the preservation and continued development of social, cultural and political traditions that shape and sustain national identity and the distinctiveness of a society. While some argue that Islam and modernisation are incompatible and to modernise Islamic countries, Islam as a religion, doctrine and political ideology should be eliminated, it is argued here that there are no inherent conflicts or contradictions between Islam and modernisation and that the Anglo-American approach is not the only path for modern societies. Muslim countries can find their own path to modernisation using Islamic principles and Shura as a political ideology. Through the application of multiple modernities, we suggest that teaching educational leadership can be effectively internationalised and modified to serve cultural and social heritage and goals of Muslim countries. Finally, we discuss the characteristics of educational leaders required for nation-building in Muslim countries, arguing that nation-building efforts should involve an extensive use of historical events, traditional narratives and literature that aim to explain and convey cultural values and national ideologies to the new generations. One approach is through hybrid curricula where international literature can be combined with material reflecting the nature and character of Muslim countries, particularly if presenting the field in an interpretive and critical manner and taking into account the collective nature of Muslim societies

Epigenetic Regulation of Apoptosis and Cell Cycle in Osteosarcoma

The role of genetic mutations in the development of osteosarcoma, such as alterations in p53 and Rb, is well understood. However, the significance of epigenetic mechanisms in the progression of osteosarcoma remains unclear and is increasingly being investigated. Recent evidence suggests that epigenetic alterations such as methylation and histone modifications of genes involved in cell cycle regulation and apoptosis may contribute to the pathogenesis of this tumor. Importantly, understanding the molecular mechanisms of regulation of these pathways may give insight into novel therapeutic strategies for patients with osteosarcoma. This paper serves to summarize the described epigenetic mechanisms in the tumorigenesis of osteosarcoma, specifically those pertaining to apoptosis and cell cycle regulation

Isospectrality for orbifold lens spaces

We answer Mark Kac’s famous question [K], “can one hear the shape of a drum?” in the positive for orbifolds that are 3-dimensional and 4-dimensional lens spaces; we thus complete the answer to this question for orbifold lens spaces in all dimensions. We also show that the coefficients of the asymptotic expansion of the trace of the heat kernel are not sufficient to determine the above results

L’effet des droits de propriété sur l’adoption des techniques de conservation des eaux et des sols par les producteurs de céréales au Burkina Faso

This article is an attempt to give an answer to the main research question entitled: what is the effect of property rights on the adoption of water and soil conservation techniques by cereal producers in Burkina Faso. The objective of this article is to evaluate the effect of property rights on the adoption of water and soil conservation techniques by cereal producers in Burkina Faso. A multivariate probit model is used on a sample of 4,813 plots from the survey carried out by the second National Land Management Program (PNGT2) in 2011 on households in Burkina Faso. The results show that formal property rights positively influence the probability of adoption of stone bunds, half-moons and hedgerows. The main conclusion of this research is that formal property rights positively influence the probability of adoption of stone bunds, half-moons and hedgerows. The article therefore recommends the use of water and soil conservation techniques by cereal producers with formal property rights over their plots.Cet article est une tentative de donner une réponse à la question principale de recherche intitulée : quel est l’effet des droits de propriété sur l’adoption des techniques de conservation des eaux et des sols par les producteurs de céréales au Burkina Faso. L’objectif de cet article est d’évaluer l’effet des droits de propriété sur l’adoption des techniques de conservation des eaux et des sols par les producteurs de céréales au Burkina Faso. Un modèle probit multivarié est utilisé sur un échantillon de 4 813 parcelles de l’enquête réalisée par le deuxième Programme National de Gestion des Terroirs (PNGT2) en 2011 sur les ménages au Burkina Faso. Les résultats montrent que les droits de propriété formels influencent positivement la probabilité d’adoption des diguettes en cordons pierreux, des demi-lunes et des haies vives. La principale conclusion de cette recherche est que les droits de propriétés formels influencent positivement la probabilité d’adoption des diguettes en cordons pierreux, des demi-lunes et des haies vives. L’article recommande par conséquent l’utilisation des techniques de conservation des eaux et des sols par les producteurs de céréales disposant de droits de propriété formels sur leurs parcelles

Everyday visual demands of people with low vision:A mixed methods real-life recording study

Research has demonstrated that low vison aids (LVAs) can have a positive impact on the functional sight of those living with sight loss. Step changes in technology are now enabling new wearable LVAs with greater potential than those available previously. For these novel devices to receive increased acceptance and therefore adoption by those with sight loss, visual task demands have to be understood more clearly in order to enable better alignment between device design and user requirements. The aim of this study was to quantify these requirements. Thirty-two participants aged 18 to 87 wore a spectacle-mounted video camera to capture and narrate all everyday situations in which they would use a "perfect" sight aid during 1 week. Captured scenes were analyzed through categorization and computational image analysis. Results showed large variation in activities and lifestyles. Participants reported no available sight aid or coping strategy for 57% of the recorded activities. Reading made up 49% of all recorded tasks, the other half comprising non-textual information. Overall, 75% of captured activities were performed ad hoc (duration of 0-5 minutes), 78% occurred indoors, 58% occurred at home, 48% were lit by natural light, 68% included the object of interest within reach, and 69% required a single focus plane only. Around half of captured objects of interest had a size of 2 degrees visual angle (2.08 logarithm of the minimum angle of resolution [logMAR]) or smaller. This study highlights the need for a sight aid that can make both textual and non-textual scenes accessible while offering flexibility to accommodate individual lifestyles