Scientists Work up a Disappearing Act
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Commencement Program
Sunday, the Sixteenth of May, Two Thousand and Ten ten o’clock in the morning ~ wallace wade stadium Duke University Commencement ~ 2010 One Hundred Fifty-Eighth Commencement Notes on Academic Dress Academic dress had its origin in the Middle Ages. When the European universities were taking form in the thirteenth and fourteenth centuries, scholars were also clerics, and they adopted Mace and Chain of Office robes similar to those of their monastic orders. Caps were a necessity in drafty buildings, and Again at commencement, ceremonial use is copes or capes with hoods attached were made of two important insignia given to Duke needed for warmth. As the control of universities University in memory of Benjamin N. Duke. gradually passed from the church, academic Both the mace and chain of office are the gifts costume began to take on brighter hues and to of anonymous donors and of the Mary Duke employ varied patterns in cut and color of gown Biddle Foundation. They were designed and and type of headdress. executed by Professor Kurt J. Matzdorf of New The use of academic costume in the United Paltz, New York, and were dedicated and first States has been continuous since Colonial times, used at the inaugural ceremonies of President but a clear protocol did not emerge until an Sanford in 1970. intercollegiate commission in 1893 recommended The Mace, the symbol of authority of the a uniform code. In this country, the design of a University, is made of sterling silver throughout. gown varies with the degree held. The bachelor’s Significance of Colors It is thirty-seven inches long and weighs about gown is relatively simple with long pointed Colors indicating fields of eight pounds. -
Millennium Development Holes
www.nature.com/nature Vol 446 | Issue no. 7134 | 22 March 2007 Millennium development holes The political commitment to helping the developing world is failing to deliver on its promises. The problem is made worse by the questionable evaluation of progress. n 2000, 189 world leaders committed to eight Millennium Devel- few developing countries have any data for around 1990, the baseline opment Goals (MDGs), ranging from halving extreme poverty and year. It is impossible to estimate progress for most of the indicators Ihunger, and rolling back killer diseases such as AIDS and malaria, over less than five years, and sparse poverty data can only be reliably to providing universal primary education. The deadline of 2015 to compared over decades. To pretend that progress towards the 2015 achieve all these ambitious goals is now rapidly approaching. goals can be accurately and continually measured is false. As a rallying cry that has pushed development up the inter national Significant efforts are now being made to improve data collection. political agenda, the goals have been an indisputable success. They Meanwhile, UN agencies fill in the missing data points using ‘model- have also, for better or worse, conferred power and legitimacy on ling’ — in practice, a recipe for potentially misleading extrapolation interests within the international aid machine, in particular the and political tampering. United Nations (UN) and the World Bank. Indeed, the lack of data makes it impossible not only to track But the goals are ultimately political promises, and as such they progress, but also to assess the effectiveness of measures taken. -
The Physics of Negative Refraction and Transformation Optics
The Physics of Negative Refraction and Transformation Optics by Wei Hsiung Wee Thesis submitted for the degree of Doctor of Philosophy Condensed Matter Theory Group Department of Physics Imperial College London June 2011 Declaration of Originality This thesis is a result of the author’s own work. All other work contained within are appropriately referenced to the best of the author’s knowledge. Abstract Whilst optics is one of the oldest field in science, there are still aspects of electromag- netism that we are only beginning to uncover. For instance, it was demonstrated that materials with simultaneously negative permittivity and permeability exhibit certain exotic behavior; where familiar physical phenomena, such as refraction, are reversed. As such, these materials came to be known as negative refractive index materials (NRIM) and their collective properties as negative refraction. One of the most important and remarkable property of NRIM is perfect lensing - the ability to transport both supra and sub-wavelength optical information from one surface (ob- ject plane) to another (image plane), forming images with unprecedented resolution, beyond the diffraction limit. Perfect lensing itself is a consequence of deeper sym- metries in electromagnetism, encapsulated in the language of transformation optics - with which we have both a descriptive tool to unify diverse electromagnetic con- figuarations, as well as a prescriptive tool to design media which bends light at will. While, such transformation medium and NRIM have been demonstrably realised using metamaterials, several challenges remain, of which loss is the major challenge. It is therefore under this trinity of concepts: metamaterials, negative refraction and transformation optics that this thesis is presented. -
Lenses Can Bend Light and Sound in Almost Any Direction 2 April 2012, by Lisa Zyga
Lenses can bend light and sound in almost any direction 2 April 2012, by Lisa Zyga a change, or gradient, in the refractive index of a lens, the scientists could create anisotropies - that is, make the lens' refractive index directionally dependent. "We explain how one can either focus or bend (at 90°, 180° and 360°) electromagnetic or pressure waves simply by creating some gradient of the refractive index, which in essence is associated with effective anisotropy," Guenneau told PhysOrg.com. "In layman's terms, we have curved the metric of space in the electromagnetic and acoustic contexts. We used realistic physical parameters and stress that one can use analogies 3D view of the electric field for a lens that bends light 90 between optics and acoustics to further the degrees. Image credit: T. M. Chang, et al. ©2012 IOP understanding: sometimes, thinking in terms of Publishing Ltd and Deutsche Physikalische Gesellschaft sound waves allows us to better grasp the foundations of transformational optics, as light waves are more elusive (light has complex physical properties such as polarization and moreover, it (PhysOrg.com) -- When an optical fiber is bent by can propagate in vacuum unlike sound waves, 90° or more, the light begins to leak away, posing which is something that still puzzles me)." a problem for fiber optics communications. But by using special lenses that can bend light by not only These GRIN lenses, which can be considered 90°, but also 180° (i.e., a U-turn) or 360° (i.e., a metamaterials and metafluids, build upon the full loop), scientists may limit light leakage in principles of the invisibility cloak, which was co- optical fibers and overcome this problem, not to discovered in the spring of 2006 by Sir John Pendry mention provide a useful material for many other of Imperial College London and Ulf Leonhardt of applications. -
Professor Sir John PENDRY Citation
Doctor of Science honoris cαusa Professor Sir John PENDRY Citation Today, we see Professor Sir John Pendry sitting altering his research focus every 10 years or so with us on the stage. In the future being created has helped. Such an approach has taken him from by the transformational work of this eminent developing the first computation techniques for physicist, we may not. For that time, just around low energy electron diffraction to the design of the corner, is not the WYSIWYG world of what novel metamaterials. Exciting旬, such materials you see is what you get. It is of flat lenses, light provide access to properties not found in nature, bending materials, and yes, practical Harry Potter opening up brave new realms that have never invisibility cloaks. been scientifically explored before. In his groundbreaking studies, Sir John has What makes Sir John’s ideas doubly exhilarating made a specialty of venturing into the previously is that he not only produces a concept. He also impossible. From these intellectual travels, the works closely with experimental physicists to Chair Professor of Solid State Physics at Imperial put his work into practice:“If you are going to College London brings back radical new ways of have all this fun with science, you must make viewing the world 一 or not viewing it in some something of 丸” he has said. In doing so, Sir cases. John has transformed the world of physics. In addition, he has re-fired the public’s imagination Relishing the challenge of spotting the anomalies about the significance of field, with the cloak that escape the attention of the rest of us, he of invisibility ironically providing a valuable hurtles forward at a pace as fast as the light he spotlight for physics’ key role in development. -
CUBA NACIONALES 1. Cuba Crea Fondo Para Financiar La Ciencia
EDITOR: NOEL GONZÁLEZ GOTERA Nueva Serie. Número 167 Diseño: Lic. Roberto Chávez y Liuder Machado. Semana 201214 - 261214 Foto: Lic. Belkis Romeu e Instituto Finlay La Habana, Cuba. CUBA NACIONALES Variadas 1. Cuba crea fondo para financiar la ciencia. Radio Rebelde, 2014.12.17 - 22:16:14 / [email protected] / Sandy Carbonell Ramos… Cuba impulsará el financiamiento de la actividad científica con el funcionamiento a partir de enero próximo del Fondo de Ciencia y Tecnología (FONDIT), informo este miércoles la ministra del sector en la Asamblea Nacional del Poder Popular. Con la presencia del miembro del Buro Político y Primer Vicepresidente de los Consejos de Estado y de Ministros, Miguel Díaz- Canel Bermúdez, la titular de Ciencia, Tecnología y Medio Ambiente (Citma), Elba Rosa Pérez Montoya, precisó que ese fondo ya existe y será anunciado ante los parlamentarios cubanos. Al intervenir en la Comisión de Educación, Cultura, Ciencia, Tecnología y Medio Ambiente, Pérez Montoya aseguró que también se ha avanzado en la política del Sistema de Ciencia, cuya propuesta está elaborada y a disposición de la Comisión Permanente de Implementación y Desarrollo de los Lineamientos para su posterior presentación al Consejo de Ministros. Las declaraciones de la ministra respondían además a los planteamientos del diputado por el municipio habanero de La Lisa, Yury Valdés Blandín, quien expuso los criterios de su comisión sobre el 1 reordenamiento de los centros de ciencia e innovación tecnológica, tema central del debate. Valdés Blandín explicó cómo a pesar de los atrasos en este proceso, los señalamientos hechos para su avance también se ven reflejados en el Decreto Ley 323 del CITMA aprobado en agosto último para regir esta tarea. -
2019 Newsletter a Message from the Chair
Quanta&Cosmos Department of Physics and Astronomy | 2019 Newsletter A Message from the Chair It is time for an update from the Department of Physics and Astronomy. The year 2019 marks some positive changes — we are onboarding three new tenure track faculty members as part of our effort to build a cluster in theoretical and computational physics. Computational techniques are playing an increasing role in physics and astrophysics research, helping one provide the missing link between analytical, numerical, and algorithmic approaches for solving fundamental problems in theoretical physics. The department has a long tradition in developing computational techniques to solve physics problems going back to the 1930s. Just 80 years ago (IEEE milestone), John Vincent Atanasoff, with his student Clifford Berry, designed and constructed the first electronic digital computer, the Atanasoff-Berry Computer, which included electronic switches, a capacitor array, and a moving drum memory to solve systems of linear equations. Today’s digital revolution was made possible by the early pioneers of computing, including Alan Turing, John von Neumann, Konrad Zuse, John Atanasoff, and many others, and it continues to enable and accelerate scientific research and our digital lifestyle of today. Clearly, past long-term investments in education and research have paid off. Our graduate and physics majors programs also received a boost this year with 17 incoming graduate students and 25 new physics majors. This brings our total numbers to 90 graduate students, 120 physics majors, and 27 postdoctoral associates. Having that many early career scientists in the department just starting their academic paths makes for an exciting learning/ research environment. -
BIOLOGY 639 SCIENCE ONLINE the Unexpected Brains Behind Blood Vessel Growth 641 THIS WEEK in SCIENCE 668 U.K
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Curriculum Vitae
Curriculum vitae DATE October 30, 2013 PERSONAL DETAILS Name: Professor Ulf Leonhardt Address: Department of Physics of Complex Systems Weizmann Institute of Science Rehovot 76100, Israel E{mail: [email protected] Phone: +972 934 6337 Mobile: +972 54 2234757 Date of birth: October 9, 1965 Nationality: Germany, UK EMPLOYMENT 2012- Weizmann Institute of Science, Israel Professor of Physics 2012-2017 South China Normal University, China Visiting Distinguished Professor 2011 University of Vienna and Austrian Academy of Sciences Visiting Professor 2008 National University of Singapore Visiting Professor 2000-2012 University of St Andrews, UK Chair in Theoretical Physics 1998{2000 Royal Institute of Technology (KTH), Sweden G¨oran{Gustafssonand Feodor{Lynen Fellow 22/04 1998 Habilitation in Theoretical Physics Title of the thesis: State reconstruction in quantum mechanics 1996{1998 University of Ulm, Germany Habilitation fellow of the German Research Council (Deutsche Forschungsgemeinschaft) 1995{1996 Oregon Center for Optics, University of Oregon, Eugene, USA Otto Hahn Fellow and Research Scholar 1994{1995 Max Planck Research Group Nonclassical Radiation Postdoctoral fellow of the Max Planck Society 1 EDUCATION 17/12 1993 PhD in Physics (Dr. rer. nat.) from Humboldt University Grade: Summa Cum Laude Title of the thesis: Quantum theory of simple optical instruments Summer 1993 Imperial College London, UK Visiting doctoral student 1992{1993 Max Planck Research Group Nonclassical Radiation at Humboldt University Berlin Doctoral student May 1990 Diploma in Physics (Dipl. Phys.) from Jena University Grade: Distinction Title of the thesis: Quantum optics of oscillator media 1987{1988 Moscow State University, Russia Exchange student, studies in quantum–field theory 1984{1990 Friedrich Schiller University Jena, Germany University student, regular university study of physics AWARDS AND FELLOWSHIPS 2012 Thousand Talents Award of China 2009 Theo Murphy Blue Skies Award of the Royal Society Research fellowship. -
Testing Hawking Radiation in Laboratory Black Hole Analogues 25 January 2019, by Ingrid Fadelli
Testing Hawking radiation in laboratory black hole analogues 25 January 2019, by Ingrid Fadelli anti-particles. Should these particles be created just outside the event horizon, the positive member of this pair of particles could escape, resulting in an observed thermal radiation emitting from the black hole. This radiation, which was later termed Hawking radiation, would hence consist of photons, neutrinos and other subatomic particles. The theory of Hawking radiation was among the first to combine concepts from quantum mechanics with Albert Einstein's theory of General Relativity. "I learned General Relativity in 1997 by lecturing a course, not by taking a course," Ulf Leonhardt, one of the researchers who carried out the recent study, told Phys.org. "This was a rather stressful experience where I was just a few weeks ahead of the students, but I really got to know General Relativity and fell in love with it. Fittingly, this also happened in Ulm, Einstein's birthplace. Since then, The parabolic mirror in the background focuses dark-red I have been looking for connections between my light into the fibre that shines bright-blue on the other field of research, quantum optics and General end. A tiny bit of the bright light is Hawking radiation, Relativity. My main goal is to demystify General which the researchers extracted and measured. Credit: Relativity. If, as I and others have shown, ordinary Drori et al. optical materials like glass act like curved spaces, then the curved space-time of General Relativity becomes something tangible, without losing its charm." Researchers at Weizmann Institute of Science and Cinvestav recently carried out a study testing the In collaboration with his first Ph.D. -
High-Tech Materials Could Render Objects Invisible
NEWS OF THE WEEK PHYSICS High-Tech Materials Could Render Objects Invisible No, this isn’t the 1 April issue of The invisibility isn’t perfect: It works only in a Science, and yes, you read the head- narrow range of wavelengths. line correctly. Materials already The authors map out the necessary speed being developed could funnel light variations and leave it to others to design the and electromagnetic radiation materials that will produce them. But around any object and render it researchers already know how to design meta- invisible, theoretical physicists pre- materials to achieve such bizarre properties, at dict online in Science this week least for radio waves, says Nader Engheta, an (www.sciencemag.org/cgi/ electrical engineer at the University of Penn- content/abstract/1125907 and … sylvania. “It’s not necessarily easy, but the 1126493). In the near future, such recipes are there,” says Engheta, who last year cloaking devices might shield sen- proposed using a metamaterial coating to sitive equipment from disruptive counteract an object’s ability to redirect light, radio waves or electric and mag- making combination nearly transparent. netic fields. Cloaks that hide objects Cloaking devices for radio waves could from prying eyes might not be much appear within 5 years, Gbur says, and cloaks further off, researchers say. for visible light are conceivable. Pendry notes The papers are “visionary,” that even a cloak for static fields would, for says George Eleftheriades, an No see? Forget the Invisible Man’s transparency potion; new example, let technicians insert sensitive elec- electrical engineer at the Univer- materials might ferry light around an object, making it invisible. -
Bending the Laws of Optics with Metamaterials: an Interview With
National Science Review INTERVIEW 5: 200–202, 2018 doi: 10.1093/nsr/nwx118 Advance access publication 20 September 2017 Special Topic: Metamaterials Bending the laws of optics with metamaterials: an interview with John Pendry By Philip Ball Downloaded from https://academic.oup.com/nsr/article/5/2/200/4209243 by guest on 23 September 2021 Metamaterials show us that nature’s laws might not always be as fixed as they seem to be. One of the laws of optics, for example, statesthat a light ray passing from one transparent medium to another—air to water or glass, say—is bent at the interface by an amount that depends on the so-called refractive indices of the two media. And all transparent materials have a refractive index greater thanthatofa vacuum (or, roughly speaking, of air), which is set equal to 1. Or do they? In the 1960s, the Russian physicist Victor Veselago explained what would be needed, in theory, for a material to have a refractive index that is not only less than 1 but in fact negative, so that itbends light the ‘wrong way’. Veselago’s idea was all but forgotten until it was unearthed in the late 1990s by electrical engineer David Smith. He was wondering ifit might be possible to make a ‘scaled-up’ version of such a material, built from ‘artificial atoms’ and later called a metamaterial, which could show this effect at longer wavelengths than those of light, in the microwave part of the spectrum. By happy coincidence, physicist SirJohn Pendry of Imperial College London, UK, had already come up with a prescription for making a similar structure from loops of wire.