Lectures and Seminars Hilary Term 2012
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The Purpose of the First World War War Aims and Military Strategies Schriften Des Historischen Kollegs
The Purpose of the First World War War Aims and Military Strategies Schriften des Historischen Kollegs Herausgegeben von Andreas Wirsching Kolloquien 91 The Purpose of the First World War War Aims and Military Strategies Herausgegeben von Holger Afflerbach An electronic version of this book is freely available, thanks to the support of libra- ries working with Knowledge Unlatched. KU is a collaborative initiative designed to make high quality books Open Access. More information about the initiative can be found at www.knowledgeunlatched.org Schriften des Historischen Kollegs herausgegeben von Andreas Wirsching in Verbindung mit Georg Brun, Peter Funke, Karl-Heinz Hoffmann, Martin Jehne, Susanne Lepsius, Helmut Neuhaus, Frank Rexroth, Martin Schulze Wessel, Willibald Steinmetz und Gerrit Walther Das Historische Kolleg fördert im Bereich der historisch orientierten Wissenschaften Gelehrte, die sich durch herausragende Leistungen in Forschung und Lehre ausgewiesen haben. Es vergibt zu diesem Zweck jährlich bis zu drei Forschungsstipendien und zwei Förderstipendien sowie alle drei Jahre den „Preis des Historischen Kollegs“. Die Forschungsstipendien, deren Verleihung zugleich eine Auszeichnung für die bisherigen Leis- tungen darstellt, sollen den berufenen Wissenschaftlern während eines Kollegjahres die Möglich- keit bieten, frei von anderen Verpflichtungen eine größere Arbeit abzuschließen. Professor Dr. Hol- ger Afflerbach (Leeds/UK) war – zusammen mit Professor Dr. Paul Nolte (Berlin), Dr. Martina Steber (London/UK) und Juniorprofessor Simon Wendt (Frankfurt am Main) – Stipendiat des Historischen Kollegs im Kollegjahr 2012/2013. Den Obliegenheiten der Stipendiaten gemäß hat Holger Afflerbach aus seinem Arbeitsbereich ein Kolloquium zum Thema „Der Sinn des Krieges. Politische Ziele und militärische Instrumente der kriegführenden Parteien von 1914–1918“ vom 21. -
Photons That Travel in Free Space Slower Than the Speed of Light Authors
Title: Photons that travel in free space slower than the speed of light Authors: Daniel Giovannini1†, Jacquiline Romero1†, Václav Potoček1, Gergely Ferenczi1, Fiona Speirits1, Stephen M. Barnett1, Daniele Faccio2, Miles J. Padgett1* Affiliations: 1 School of Physics and Astronomy, SUPA, University of Glasgow, Glasgow G12 8QQ, UK 2 School of Engineering and Physical Sciences, SUPA, Heriot-Watt University, Edinburgh EH14 4AS, UK † These authors contributed equally to this work. * Correspondence to: [email protected] Abstract: That the speed of light in free space is constant is a cornerstone of modern physics. However, light beams have finite transverse size, which leads to a modification of their wavevectors resulting in a change to their phase and group velocities. We study the group velocity of single photons by measuring a change in their arrival time that results from changing the beam’s transverse spatial structure. Using time-correlated photon pairs we show a reduction of the group velocity of photons in both a Bessel beam and photons in a focused Gaussian beam. In both cases, the delay is several microns over a propagation distance of the order of 1 m. Our work highlights that, even in free space, the invariance of the speed of light only applies to plane waves. Introducing spatial structure to an optical beam, even for a single photon, reduces the group velocity of the light by a readily measurable amount. One sentence summary: The group velocity of light in free space is reduced by controlling the transverse spatial structure of the light beam. Main text The speed of light is trivially given as �/�, where � is the speed of light in free space and � is the refractive index of the medium. -
Arxiv:1603.00726V1 [Physics.Optics] 2 Mar 2016
Single-pixel 3D imaging with time-based depth resolution Ming-Jie Sun,1, 2, ∗ Matthew. P. Edgar,2 Graham M. Gibson,2 Baoqing Sun,2 Neal Radwell,2 Robert Lamb,3 and Miles J. Padgett2, y 1Department of Opto-electronic Engineering, Beihang University, Beijing, 100191, China 2SUPA, School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, UK 3Selex ES, Edinburgh, UK Time-of-flight three dimensional imaging is an important tool for many applications, such as object recognition and remote sensing. Unlike conventional imaging approach using pixelated detector array, single-pixel imaging based on projected patterns, such as Hadamard patterns, utilises an alternative strategy to acquire information with sampling basis. Here we show a modified single-pixel camera using a pulsed illumi- nation source and a high-speed photodiode, capable of reconstructing 128×128 pixel resolution 3D scenes to an accuracy of ∼ 3 mm at a range of ∼ 5 m. Furthermore, we demonstrate continuous real-time 3D video with a frame-rate up to 12 Hz. The sim- plicity of the system hardware could enable low-cost 3D imaging devices for precision ranging at wavelengths beyond the visible spectrum. Introduction Whilst a variety of 3D imaging technologies are suited for different applications, time-of-flight (TOF) systems have set the benchmark for performance with regards to a combination of accuracy and operating range. Time-of-flight imaging is performed by illuminating a scene with a pulsed light source and observing the back-scattered light. Correlating the detection time of the back-scattered light with the time of the illumination pulse allows the distance, d, to objects within the scene to be estimated by d = tc=2, where t is the TOF and c is the propagation speed of light. -
PRISM Vol 3, No 1
PRISM❖ Vol. 3, no. 1 12/2011 PRISM Vol. 3, no. 1 3, no. Vol. ❖ 12/2011 www.ndu.edu A JOURNAL OF THE CENTER FOR COMPLEX OPERATIONS PRISM ABOUT CENTER FOR COMPLEX OPERATIONS (CCO) CCO WAS ESTABLISHED TO: PRISM is published by the National Defense University Press for the Center for ❖❖ Serve as an information clearinghouse and knowledge Enhancing the U.S. Government’s Ability to manager for complex operations training and education, PUBLISHER Complex Operations. PRISM is a security studies journal chartered to inform members of U.S. Federal agencies, allies, and other partners on complex and Prepare for Complex Operations acting as a central repository for information on areas Dr. Hans Binnendijk integrated national security operations; reconstruction and nation-building; such as training and curricula, training and education pro- CCO, a center within the Institute for National Strategic relevant policy and strategy; lessons learned; and developments in training and vider institutions, complex operations events, and subject EDITOR AND RESEARCH DIRECTOR Studies at National Defense University, links U.S. education to transform America’s security and development apparatus to meet matter experts Government education and training institutions, including Michael Miklaucic tomorrow’s challenges better while promoting freedom today. related centers of excellence, lessons learned programs, ❖❖ Develop a complex operations training and education com- and academia, to foster unity of effort in reconstruction munity of practice to catalyze innovation and development DEVELOPMENTAL EDITOR and stability operations, counterinsurgency, and irregular of new knowledge, connect members for networking, share Melanne A. Civic, Esq. COMMUNICATIONS warfare—collectively called “complex operations.” existing knowledge, and cultivate foundations of trust and The Department of Defense, with support from the habits of collaboration across the community Constructive comments and contributions are important to us. -
Download the Annual Review PDF 2016-17
Annual Review 2016/17 Pushing at the frontiers of Knowledge Portrait of Dr Henry Odili Nwume (Brasenose) by Sarah Jane Moon – see The Full Picture, page 17. FOREWORD 2016/17 has been a memorable year for the country and for our University. In the ever-changing and deeply uncertain world around us, the University of Oxford continues to attract the most talented students and the most talented academics from across the globe. They convene here, as they have always done, to learn, to push at the frontiers of knowledge and to improve the world in which we find ourselves. One of the highlights of the past twelve months was that for the second consecutive year we were named the top university in the world by the Times Higher Education Global Rankings. While it is reasonable to be sceptical of the precise placements in these rankings, it is incontrovertible that we are universally acknowledged to be one of the greatest universities in the world. This is a privilege, a responsibility and a challenge. Other highlights include the opening of the world’s largest health big data institute, the Li Ka Shing Centre for Health Information and Discovery, and the launch of OSCAR – the Oxford Suzhou Centre for Advanced Research – a major new research centre in Suzhou near Shanghai. In addition, the Ashmolean’s success in raising £1.35 million to purchase King Alfred’s coins, which included support from over 800 members of the public, was a cause for celebration. The pages that follow detail just some of the extraordinary research being conducted here on perovskite solar cells, indestructible tardigrades and driverless cars. -
The Utility of Military Force and Public Understanding in Today's Britain
EUROPE HEW STRACHAN, RUTH HARRIS The Utility of Military Force and Public Understanding in Today’s Britain For more information on this publication, visit www.rand.org/t/RRA213-1 The Global Strategic Partnership (GSP), a consortium of research, academic and industry organisations that is led by RAND Europe, provides ongoing analytical support to the UK Ministry of Defence. Published by the RAND Corporation, Santa Monica, Calif., and Cambridge, UK © Copyright 2020 RAND Corporation R® is a registered trademark. RAND Europe is a not-for-profit research organisation that helps to improve policy and decision making through research and analysis. RAND’s publications do not necessarily reflect the opinions of its research clients and sponsors. Limited Print and Electronic Distribution Rights This document and trademark(s) contained herein are protected by law. This representation of RAND intellectual property is provided for noncommercial use only. Unauthorized posting of this publication online is prohibited. Permission is given to duplicate this document for personal use only, as long as it is unaltered and complete. Permission is required from RAND to reproduce, or reuse in another form, any of its research documents for commercial use. For information on reprint and linking permissions, please visit www.rand.org/pubs/permissions. Support RAND Make a tax-deductible charitable contribution at www.rand.org/giving/contribute www.rand.org www.randeurope.org Table of Contents Table of Contents .................................................................................................................................... -
Comparative Humanities Review Volume 3 Translation: Comparative Perspectives Article 14 (Spring 2009)
Comparative Humanities Review Volume 3 Translation: Comparative Perspectives Article 14 (Spring 2009) 2009 Comparative Humanities Review Follow this and additional works at: http://digitalcommons.bucknell.edu/chr Recommended Citation (2009) "Comparative Humanities Review," Comparative Humanities Review: Vol. 3, Article 14. Available at: http://digitalcommons.bucknell.edu/chr/vol3/iss1/14 This Full Issue is brought to you for free and open access by Bucknell Digital Commons. It has been accepted for inclusion in Comparative Humanities Review by an authorized administrator of Bucknell Digital Commons. For more information, please contact [email protected]. Translation: Comparative Perspectives Vol. 3 (Spring 2009) Edited by A. Joseph McMullen The Comparative Humanities Review 3 Translation: Comparative Perspectives Edited by A. Joseph McMullen A Student Publication of The Comparative Humanities Department Bucknell University Lewisburg, PA The Comparative Humanities Review is a student-run journal dedicated to the support and distribution of undergraduate scholarship in the humanities. We welcome submissions that are comparative in nature and employ any discipline in the humanities. Contributions should be written when the author is completing his or her undergraduate degree. For more information, contact the Editor-in-Chief by visiting the Web site below. Access the journal online: http://www.orgs.bucknell.edu/comp_hum_rev/index.html Copyright (c) 2009 All rights reserved. Cover: Preparations to burn the body of William Tyndale from John Foxe’s Book of Martyrs Source: Lacey Baldwin Smith, The Horizon Book of the Elizabethan World (New York: American Heritage, 1967), 73. 3 Translation: Comparative Perspectives Contents Translation and Film: Slang, Dialects, Accents and Multiple Languages / Allison Rittmayer … 1 Philosophy, Abstract Thought, and the Dilemmas of Philosophy / James Rickard … 13 The Great War Seen Through the Comparative Lens / Steven L. -
Arxiv:2005.03760V1 [Physics.Class-Ph] 4 May 2020
Amplification of waves from a rotating body Marion Cromb,1 Graham M. Gibson,1 Ermes Toninelli,1 Miles J. Padgett,1, ∗ Ewan M. Wright,2 and Daniele Faccio1, 2, y 1School of Physics and Astronomy, University of Glasgow, Glasgow, G12 8QQ, UK 2College of Optical Sciences, University of Arizona, Tucson, Arizona 85721, USA (Dated: May 11, 2020) In 1971 Zel'dovich predicted that quantum fluctuations and classical waves reflected from a ro- tating absorbing cylinder will gain energy and be amplified. This key conceptual step towards the understanding that black holes may also amplify quantum fluctuations, has not been verified ex- perimentally due to the challenging experimental requirements on the cylinder rotation rate that must be larger than the incoming wave frequency. Here we experimentally demonstrate that these conditions can be satisfied with acoustic waves. We show that low-frequency acoustic modes with orbital angular momentum are transmitted through an absorbing rotating disk and amplified by up to 30% or more when the disk rotation rate satisfies the Zel'dovich condition. These experiments address an outstanding problem in fundamental physics and have implications for future research into the extraction of energy from rotating systems. Introduction. In 1969, Roger Penrose proposed a an amplifier. Outgoing waves then have an increased am- method to extract the rotational energy of a rotating plitude, therefore extracting energy from the rotational black hole, now known as Penrose superradiance [1]. Pen- energy of the body in the same spirit of Penrose's pro- rose suggested that an advanced civilisation might one posal. day be able to extract energy from a rotating black hole Satisfying the condition in Eq. -
Israel—Drifting Towards Disaster? BRONWEN MADDOX
What if football had different rules? p20 ISSUE 220 | JULY 2014 www.prospectmagazine.co.uk JULY 2014 | £4.95 Israel—drifting towards disaster? BRONWEN MADDOX ISRAEL—DRIFTING TOWARDS DISASTER? ISRAEL—DRIFTING TOWARDS Plus Ed Miliband’s real problem PETER KELLNER How Germany remembers WW1 HEW STRACHAN The man who saved the world STEPHANIE FLANDERS Surviving teleportation JIM HOLT Why you should move to Manchester JONATHAN DERBYSHIRE Also Rebecca Front, Christine Ockrent, Sebastian Smee, AC Grayling, Ramachandra Guha, Jonathan Portes C PROSPECT JULY Foreword Democracy’s great test 25 Sackville Street, London W1S 3AX Publishing 020 7255 1281 Editorial 020 7255 1344 Fax 020 3031 1191 Email [email protected] [email protected] Website www.prospectmagazine.co.uk Editorial Editor and Chief Executive Bronwen Maddox Editor-at-Large David Goodhart Deputy Editor Jay Elwes The biggest test of democracy is whether it produces Managing Editor Jonathan Derbyshire Arts & Books Editor David Wolf governments that can solve a country’s greatest problems. Creative Director David Killen Production Editor Jessica Abrahams Budget defi cits, in the case of Europe; Hindu-Muslim clashes, Digital Editor Serena Kutchinsky Assistant Digital Editor Josh Lowe in the case of India (p46); a vulnerable economy and a failure Publishing to reach a deal with the Palestinians, in the case of Israel President & co-founder Derek Coombs Commercial Director Alex Stevenson (p24). Right now, the best-known thing that Jean-Claude Publishing Consultant -
PDF Program Download
May 17-20, 2021 | Virtual Conference 2021 Please visit our website for more information! CONFERENCE i2mtc2021.ieee-ims.org PROGRAM Sponsors and Organizers SPONSORS AND ORGANIZERS Table of Contents Welcome Message from the General Co-Chairs ........................................................................................................ 3 I2MTC 2021 Organizing Committee ............................................................................................................................... 5 I2MTC Board of Directors ................................................................................................................................................ 6 I2MTC 2021 Associate Technical Program Chairs .................................................................................................... 7 Special Session Organizers ............................................................................................................................................ 8 I2MTC 2021 Reviewers ...................................................................................................................................................... 9 I2MTC 2021 Conference Sponsors .............................................................................................................................. 11 I2MTC 2021 Plenary Speakers ...................................................................................................................................... 12 I2MTC 2021 Plenary Speakers (continued) .............................................................................................................. -
A Mind-Bending Technology Goes Mainstream Electronic Line Calling Get Closer to the Hawk-Eye Innovations, UK UK’S Game-Changing Technology
Taiwan and the one-China fiction IS up against the wall in Mosul In praise of quinoa, millet and teff Is there a bubble in the markets? MARCH 11TH–17TH 2017 Quantum leaps A mind-bending technology goes mainstream Electronic Line Calling Get closer to the Hawk-Eye Innovations, UK UK’s game-changing technology. Millimetres separate victory from defeat in any sport. Now used by 20 sports in over 80 tournaments worldwide, Hawk-Eye’s electronic line calling service is making sport fairer, smarter and more spectacular. It’s just one example of the ingenuity that the UK’s 5.5 million companies can offer your business. Find your ideal trade partner at great.gov.uk Contents The Economist March 11th 2017 3 5 The world this week 32 WikiLeaks, again The spy who came in for the code Leaders 33 Chicago 7 Subatomic opportunities This American carnage Quantum leaps 33 Campus free speech 8 Britain’s budget Blue on blue Spreadsheets v politics 34 Lexington 8 Stockmarkets Safety politics Bubble-spotting 9 Geopolitics The Americas Ryancare The House proposal One China, many meanings 35 Brazil’s president to amend Obamacare may 10 Food snobbery and Accidental, consequential break parts of America’s economics health-insurance market, In praise of quinoa 36 Race in the Caribbean On the cover Curry cultures page 30 After a century stuck in 38 Bello textbooks, mind-bending Letters Stealing Venezuela quantum effects are about to 11 On renewable energy power mainstream innovation: leader, page 7. Middle East and Africa Big firms and startups are Briefing 39 Defeating -
The Twist in Light's Tail Miles Padgett FRS FRSE
The Twist in Light’s Tail Miles Padgett FRS FRSE Kelvin Chair of Natural Philosophy follow me on Twitter @MilesPadgett Light beams carry a Linear Momentum • Light carries a linear momentum – Force exerted = Power/c • Laser pointer exerts 10-11 N • Strong enough to move cells and bacterial • Or (with a very large sail!) a spacecraft…. Light’s Angular Momentum in History We now refer to this as the SPIN angular momentum of the photon But light has an extra angular momentum in addition to photon spin (this extra momentum is needed for some rare atomic transitions) Getting started on Orbital Angular Momentum of Light • 1992, Allen, Beijersbergen, Spreeuw and Woerdman Miles Padgett • 1994, Les meets Miles at dinner…... Orbital Angular Momentum from helical phase fronts E E B B S S Sθ = 0 Sθ ≠ 0 Helical phasefronts and orbtial angular momentum • Phase cross-section ℓ= 0 Φ = exp (iℓφ) ℓ = 0, plane wave ℓ = 1, helical wave ℓ = 2, double helix ℓ= 1 ℓ = 3, pasta fusilli etc. 2π ℓ= 2 Phase 0 x-section of helical wave ℓ = 3 Intensity Phase Angular momentum in terms of photons • Spin angular momentum Polarisation σ = +1 Circular – Circular polarisation σ" per photon • Orbital angular momentum – Helical phasefronts σ = -1 ℓ" per photon Helical Phasefronts ℓ = -1 ℓ = 0 ℓ = 1 ℓ = 2 ℓ = 3 A double-start helix (ℓ=2): Home improvments Chambord castle (chateaux de la Loire) Making helical phasefronts • Pass plane-wave through a spiral- phase plate (thickness α φ) – step height= ℓλ/(n-1) Designing helical phase hologram ! Spiral Phase-plate s= ℓλ/(n-1) s 2π • Holographically + = e.g.