DOCSLIB.ORG

Research Experience for Undergraduates Program Research Reports

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Research Experience for Undergraduates Program Research Reports Research Experience for Undergraduates Program Research Reports Indiana University, Bloomington Summer 2019 Contents Unusual Topographical Features of Laplacian Eigenfunctions .. 5 Kelly Chen and Olti Myrtaj Extremal Length of Winding Curves .................. 15 Max Newman Mixing of Random Walks on Punctured Graphs .......... 32 Chung Kyong Nguen Cauchy-Fueter Formulas for Universal Clifford Algebras of In- definite Signature ............................ 43 Ely Sandine On the Large Time Diffusion of Isotropic and Anisotropic Particles 72 Mikhail Sweeney Bernoulli Percolation on Hyperbolic Graphs ............. 92 Christine Sullivan Spectral Properties of Reversible Indel Models ........... 105 Linden Yuan Preface During the summer of 2019 eight students participated in the Research Experi- ence for Undergraduates program in Mathematics at Indiana University. This program was sponsored by the National Science Foundation through the Re- search Experience for Undergraduates grant DMS-1461061 and the Department of Mathematics at Indiana University, Bloomington. The program ran for eight weeks, from June 3 through July 26, 2019. Eight faculty served as research advisers to the students from Indiana University: Kelly Chen and Olti Myrtaj were advised by Chris Judge. • Max Newman was advised by Dylan Thurston. • Chung Kyong Nguen was advised by Graham White. • Ely Sandine was advised by Matvei Libine. • Mikhail Sweeney and Linden Yuan was advised by Louis Fan. • Christine Sullivan was advised by Chris Connell. • Following the introductory pizza party, students began meeting with their faculty mentors and continued to do so throughout the next eight weeks. The students also participated in a number of social events and educational oppor- tunities and field trips. Individual faculty gave talks throughout the program on their research, about two a week. Students also received LaTeX training in a series of work- shops. Other opportunities included the option to participate in a GRE and subject test preparation seminar. Additional educational activities included tours of the library, the Low Energy Neutron Source facility, the Slocum puz- zle collection at the Lilly Library, and self guided tours of the art museum. Students presented their work to faculty mentors and their peers at various times. This culminated in their presentations both in poster form and in talks at the statewide Indiana Summer Undergraduate Research conference which was hosted at Indiana University - Purdue University at Indianapolis. On the lighter side, students were treated to weekly board game nights as well as the opportunity to do some local hiking. They also enjoyed a night of \laser tag" courtesy of the Department of Mathematics. Contents 3 The summer REU program required the help and support of many different groups and individuals to make it a success. We foremost thank the National Science Foundation and the Indiana University Bloomington Department of Mathematics without whose support this program could not exist. We espe- cially thank our staff member Mandie McCarty for coordinating the complex logistical arrangments (housing, paychecks, information packets, meal plans, frequent shopping for snacks). Additional logistical support was provided by the Department of Mathematics and our chair, Elizabeth Housworth. We are in particular thankful to Jeff Taylor for the computer support he provided. Thanks also go to those faculty who served as mentors and those who gave lectures. We thank David Baxter of the Center for Exploration of Energy and Matter (nee IU cyclotron facility) for past personal tours of the LENS facility and his infor- mative lectures. Thanks to Andrew Rhoda for his tour of the Slocum Puzzle Collection. Chris Connell September, 2019 Contents 4 Figure 1: REU Participants, from left to right: Chris Connell, Kelly Chen, Mikhail Sweeney, Ely Sandine, Max Newman, Linden Yuan, Olti Myrtaj, Chris- tine Sullivan and Chung Kyong Nguen (not pictured). Unusual Topographical Features of Laplacian Eigenfunctions Kelly Chen∗ Olti Myrtaj† [email protected] [email protected] Summer 2019 Abstract Solutions to the Laplace eigenvalue problem satisfying Dirichlet boundary conditions on a rectangular region of the plane are well known. In this work, we study interesting features of the level sets of such eigenfunctions. We consider the possibility of degenerate critical points with Poincar´e-Hopfindex 0, which correspond to cusp-like points on the level sets. In particular, we construct a one-parameter family of eigenfunctions and prove the existence of an index-0 critical point. 1 1 Introduction Let Ω be a domain with piecewise smooth boundary. A smooth function ψ :Ω R is called a Dirichlet eigenfunction of the Laplacian if and only if there exists a real number λ such that → ∆ψ(x, y) = λ ψ(x, y) for (x, y) Ω, (1) ψ−(x, y) = 0 · for (x, y) ∈ ∂Ω. ∈ The number λ is called the eigenvalue associated with the eigenfunction ψ. It is known [Ulb76] that for a generic choice of domain, the critical points of each eigenfunction are nondegenerate. In particular, there are no zeros of the gradient vector field ψ that have Poincar´e-Hopfindex equal to zero. (Lemma 2.5 describes the connection between the index and the nondegeneracy∇ of a critical point.) We restrict our attention to the case where Ω is the square [0, π] [0, π], which is not a generic domain. We show that in this case, there are in fact critical points of index 0: × Theorem 1.1. There exists a Dirichlet function of the Laplacian on [0, π] [0, π] with an index-0 critical point in (0, π) (0, π). × × On the square, one may verify that if m and n are integers, then the function ψm,n(x, y) = sin (mx) sin (ny) 2 2 is a solution to (1) with λ = λm,n = m + n . In fact, it is is well-known [Crn-Hlb, pp. 300-301] that each eigenvalue has the form m2 + n2, where m and n are integers, and a function ψ is a Dirichlet eigenfunction of the Laplacian with eigenvalue λ if and only if ψ = am,nψm,n, 2 2 m +Xn =λ where am,n are real numbers. In this paper, we consider λ = 65, the smallest λ that generates a four-dimensional eigenspace. We observe that 12 + 82 = 42 + 72 = 65, so we construct the linear combination f(x, y) = a ψ (x, y) + a ψ (x, y) + a ψ (x, y) + a ψ (x, y). 1,8 · 1,8 4,7 · 4,7 8,1 · 8,1 7,4 · 7,4 ∗Massachusetts Institute of Technology †Virginia Tech 1This material is based upon work supported by the National Science Foundation under Grant No. DMS-1461061. 1 We study the one-parameter family of eigenfunctions f t(x, y) = cos(t) sin(x) sin(8y) + sin(t) sin(4x) sin(7y), t [0, π], ∈ which contains all possible f with a8,1 = a7,4 = 0, up to scalar multiplication. To prove Theorem 1.1, we show that there exists a t such that f t has an index-0 critical point. 2 Preliminaries Recall the following definitions: 2 Definition 2.1. A function g : R R has a critical point at (x0, y0) if and only if the gradient g(x, y) = (gx(x, y), → ∇ gy(x, y)) is the zero vector at (x0, y0). Definition 2.2. A critical point (x0, y0) of g is called degenerate if the Hessian gxx(x, y) gxy(x, y) g (x, y) g (x, y) yx yy has determinant equal to 0 at (x0, y0). 2 2 2 Definition 2.3. Let v: R R , where v = (v1, v2), be a smooth vector field, and let γ be a simple closed curve in → R2. If v does not vanish on γ, then the Poincar`e-Hopfindex (or simply index) of v along γ is given by 1 v dv v dv ind(v, γ) = 1 2 − 2 1 . (2) 2π v2 + v2 Zγ 1 2 2 2 Note that in order for ind(v, γ) to be well-defined, v1 + v2 must be nonzero on γ. If v is the gradient vector field of a function g : R2 R, then this condition is equivalent to g having no critical points on γ. Next, we consider→ some properties of the index and some relevant examples. Proposition 2.4. Let v be a smooth vector field and let γ be a smooth simple closed curve. Then ind(v, γ) is an integer. Proof. Abusing notation slightly, we let γ :[a, b] R2 be a parameterization of γ. If we define → x dy y dx ω := − x2 + y2 then v1dv2 v2dv1 v∗(ω) = 2 − 2 . v1 + v2 Therefore, by a standard fact concerning differential forms we find that v1dv2 v2dv1 − = v∗(ω) = ω. v2 + v2 Zγ 1 2 Zγ Zv(γ) The curve v(γ) is a closed curve—not necessarily simple—that does not contain the origin since v = 0 on γ. Define 6 α :[a, b] R2 by → v γ(t) α(t) = ◦ . v γ(t) | ◦ | Then the image of α lies in the unit circle. Moreover, a straightforward argument shows that (v γ)∗ω = α∗ω, and so ◦ ω = ω. Zv(γ) Zα 2 1 2 2 To be more precise, γ is an oriented curve—that is, an equivalence class of C paths where two paths p:[a, b] R and p0 :[a0, b0] R 1 → → are equivalent if and only if there exists a strictly increasing C map φ:[a, b] [a0, b0] such that p = p0 φ. For simplicity, we will not explicitly state this again in the rest of the paper. → ◦ 2 Define the map p from R to the unit circle by p(t) = (cos(t), sin(t)). A straightforward calculation shows that p∗(ω) = dt. Since [a, b] is contractible, the path lifting lemma implies that there exists a path α :[a, b] R so that α(t) = p α(t).
Load more

Recommended publications
  • To What Extent Did British Advancements in Cryptanalysis During World War II Influence the Development of Computer Technology?
    Portland State University PDXScholar Young Historians Conference Young Historians Conference 2016 Apr 28th, 9:00 AM - 10:15 AM To What Extent Did British Advancements in Cryptanalysis During World War II Influence the Development of Computer Technology? Hayley A. LeBlanc Sunset High School Follow this and additional works at: https://pdxscholar.library.pdx.edu/younghistorians Part of the European History Commons, and the History of Science, Technology, and Medicine Commons Let us know how access to this document benefits ou.y LeBlanc, Hayley A., "To What Extent Did British Advancements in Cryptanalysis During World War II Influence the Development of Computer Technology?" (2016). Young Historians Conference. 1. https://pdxscholar.library.pdx.edu/younghistorians/2016/oralpres/1 This Event is brought to you for free and open access. It has been accepted for inclusion in Young Historians Conference by an authorized administrator of PDXScholar. Please contact us if we can make this document more accessible: [email protected]. To what extent did British advancements in cryptanalysis during World War 2 influence the development of computer technology? Hayley LeBlanc 1936 words 1 Table of Contents Section A: Plan of Investigation…………………………………………………………………..3 Section B: Summary of Evidence………………………………………………………………....4 Section C: Evaluation of Sources…………………………………………………………………6 Section D: Analysis………………………………………………………………………………..7 Section E: Conclusion……………………………………………………………………………10 Section F: List of Sources………………………………………………………………………..11 Appendix A: Explanation of the Enigma Machine……………………………………….……...13 Appendix B: Glossary of Cryptology Terms.…………………………………………………....16 2 Section A: Plan of Investigation This investigation will focus on the advancements made in the field of computing by British codebreakers working on German ciphers during World War 2 (1939­1945).
    [Show full text]
  • The Eagle 2005
    CONTENTS Message from the Master .. .. .... .. .... .. .. .. .. .. .... ..................... 5 Commemoration of Benefactors .. .............. ..... ..... ....... .. 10 Crimes and Punishments . ................................................ 17 'Gone to the Wars' .............................................. 21 The Ex-Service Generations ......................... ... ................... 27 Alexandrian Pilgrimage . .. .. .. .. .. .. .. .. .. .. .. .................. 30 A Johnian Caricaturist Among Icebergs .............................. 36 'Leaves with Frost' . .. .. .. .. .. .. ................ .. 42 'Chicago Dusk' .. .. ........ ....... ......... .. 43 New Court ........ .......... ....................................... .. 44 A Hidden Treasure in the College Library ............... .. 45 Haiku & Tanka ... 51 and sent free ...... 54 by St John's College, Cambridge, The Matterhorn . The Eagle is published annually and other interested parties. Articles members of St John's College .... 55 of charge to The Eagle, 'Teasel with Frost' ........... should be addressed to: The Editor, to be considered for publication CB2 1 TP. .. .. .... .. .. ... .. ... .. .. ... .... .. .. .. ... .. .. 56 St John's College, Cambridge, Trimmings Summertime in the Winter Mountains .. .. ... .. .. ... ... .... .. .. 62 St John's College Cambridge The Johnian Office ........... ..... .................... ........... ........... 68 CB2 1TP Book Reviews ........................... ..................................... 74 http:/ /www.joh.cam.ac.uk/ Obituaries
    [Show full text]
  • Alan Turing's Automatic Computing Engine
    5 Turing and the computer B. Jack Copeland and Diane Proudfoot The Turing machine In his first major publication, ‘On computable numbers, with an application to the Entscheidungsproblem’ (1936), Turing introduced his abstract Turing machines.1 (Turing referred to these simply as ‘computing machines’— the American logician Alonzo Church dubbed them ‘Turing machines’.2) ‘On Computable Numbers’ pioneered the idea essential to the modern computer—the concept of controlling a computing machine’s operations by means of a program of coded instructions stored in the machine’s memory. This work had a profound influence on the development in the 1940s of the electronic stored-program digital computer—an influence often neglected or denied by historians of the computer. A Turing machine is an abstract conceptual model. It consists of a scanner and a limitless memory-tape. The tape is divided into squares, each of which may be blank or may bear a single symbol (‘0’or‘1’, for example, or some other symbol taken from a finite alphabet). The scanner moves back and forth through the memory, examining one square at a time (the ‘scanned square’). It reads the symbols on the tape and writes further symbols. The tape is both the memory and the vehicle for input and output. The tape may also contain a program of instructions. (Although the tape itself is limitless—Turing’s aim was to show that there are tasks that Turing machines cannot perform, even given unlimited working memory and unlimited time—any input inscribed on the tape must consist of a finite number of symbols.) A Turing machine has a small repertoire of basic operations: move left one square, move right one square, print, and change state.
    [Show full text]
  • Simply Turing
    Simply Turing Simply Turing MICHAEL OLINICK SIMPLY CHARLY NEW YORK Copyright © 2020 by Michael Olinick Cover Illustration by José Ramos Cover Design by Scarlett Rugers All rights reserved. No part of this publication may be reproduced, distributed, or transmitted in any form or by any means, including photocopying, recording, or other electronic or mechanical methods, without the prior written permission of the publisher, except in the case of brief quotations embodied in critical reviews and certain other noncommercial uses permitted by copyright law. For permission requests, write to the publisher at the address below. [email protected] ISBN: 978-1-943657-37-7 Brought to you by http://simplycharly.com Contents Praise for Simply Turing vii Other Great Lives x Series Editor's Foreword xi Preface xii Acknowledgements xv 1. Roots and Childhood 1 2. Sherborne and Christopher Morcom 7 3. Cambridge Days 15 4. Birth of the Computer 25 5. Princeton 38 6. Cryptology From Caesar to Turing 44 7. The Enigma Machine 68 8. War Years 85 9. London and the ACE 104 10. Manchester 119 11. Artificial Intelligence 123 12. Mathematical Biology 136 13. Regina vs Turing 146 14. Breaking The Enigma of Death 162 15. Turing’s Legacy 174 Sources 181 Suggested Reading 182 About the Author 185 A Word from the Publisher 186 Praise for Simply Turing “Simply Turing explores the nooks and crannies of Alan Turing’s multifarious life and interests, illuminating with skill and grace the complexities of Turing’s personality and the long-reaching implications of his work.” —Charles Petzold, author of The Annotated Turing: A Guided Tour through Alan Turing’s Historic Paper on Computability and the Turing Machine “Michael Olinick has written a remarkably fresh, detailed study of Turing’s achievements and personal issues.
    [Show full text]
  • The Influence of ULTRA in the Second World War [ Changed 26Th November 1996 ]
    The Influence of ULTRA in the Second World War [ Changed 26th November 1996 ] Last year Sir Harry Hinsley kindly agreed to speak about Bletchley Park, where he worked during the Second World War. We are pleased to present a transcript of his talk. Sir Harry Hinsley is a distinguished historian who during the Second World War worked at Bletchley Park, where much of the allied forces code-breaking effort took place. We are pleased to include here a transcript of his talk, and would like to thank Susan Cheesman for typing the first draft and Keith Lockstone for adding Sir Harry's comments and amendments. Security Group Seminar Speaker: Sir Harry Hinsley Date: Tuesday 19th October 1993 Place: Babbage Lecture Theatre, Computer Laboratory Title: The Influence of ULTRA in the Second World War Ross Anderson: It is a great pleasure to introduce today's speaker, Sir Harry Hinsley, who actually worked at Bletchley from 1939 to 1946 and then came back to Cambridge and became Professor of the History of International Relations and Master of St John's College. He is also the official historian of British Intelligence in World War II, and he is going to talk to us today about Ultra. Sir Harry: As you have heard I've been asked to talk about Ultra and I shall say something about both sides of it, namely about the cryptanalysis and then on the other hand about the use of the product - of course Ultra was the name given to the product. And I ought to begin by warning you, therefore, that I am not myself a mathematical or technical expert.
    [Show full text]
  • Books in Brief Deaths Are Greatly Exaggerated
    BOOKS & ARTS COMMENT Pennington argues that predictions of a coming antibiotics Armageddon leading to a substantial increase in infection-related Books in brief deaths are greatly exaggerated. On this point, I take a more cautious line. It is true that Prof: Alan Turing Decoded careful management and aseptic technique Dermot Turing ThE HISToRY PRESS (2015) can have an important role in husbanding a Computing pioneer Alan Turing has been justly and amply lauded, dwindling supply of drugs effective against not least in these pages (see Nature 515, 195–196 (2014) and nature. the most serious infections. However, Pen- com/turing). Now, a biography by his nephew, Dermot Turing, offers nington does not devote sufficient space to new sources and a refreshingly familial tone. We see the stubbornly the factors that have led the antibiotic-devel- original young Alan finding his way in maths and society; mentors opment pipeline to dry up in recent years. such as Max Newman, who kick-started Turing’s obsession with He almost trivializes the difficulties in iden- machines; the design of the electromechanical ‘bombe’ that helped tifying relevant natural products or chemical to crack the Enigma cipher; and a sensitive reappraisal of Turing’s constructs and developing them into usable suspected suicide. A measured portrait at ease with its subject. drugs, simply writing: “New antimicrobials will be very welcome. Getting them ready for rollout will be expensive and will take years.” The Cabaret of Plants: Botany and the Imagination And he skates over structural problems in the Richard Mabey PRoFILE (2015) pharmaceutical industry: we urge pharma to As a celebrant of the botanical, Richard Mabey has few peers.
    [Show full text]
  • De-Mythologising the Early History of Modern British Computing. David Anderson
    Contested Histories: De-Mythologising the Early History of Modern British Computing. David Anderson To cite this version: David Anderson. Contested Histories: De-Mythologising the Early History of Modern British Com- puting.. IFIP WG 9.7 International Conference on History of Computing (HC) / Held as Part of World Computer Congress (WCC), Sep 2010, Brisbane, Australia. pp.58-67, 10.1007/978-3-642-15199-6_7. hal-01059593 HAL Id: hal-01059593 https://hal.inria.fr/hal-01059593 Submitted on 1 Sep 2014 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Distributed under a Creative Commons Attribution| 4.0 International License Contested Histories: De-Mythologising the Early History of Modern British Computing. David Anderson University of Portsmouth, “The Newmanry”, 36-40 Middle Street, Portsmouth, Hants, United Kindom, PO5 4BT Abstract A challenge is presented to the usual account of the development of the Manchester Baby which focuses on the contribution made to the project by the topologist M.H.A. (Max) Newman and other members of the Dept. of Mathematics. Based on an extensive re-examination of the primary source material, it is suggested that a very much more significant role was played by mathematicians than is allowed for in the dominant discourse.
    [Show full text]
  • Profalanturing-Decoded-Biography
    CONTENTS Title Introduction 1. Unreliable Ancestors 2. Dismal Childhoods 3. Direction of Travel 4. Kingsman 5. Machinery of Logic 6. Prof 7. Looking Glass War 8. Lousy Computer 9. Taking Shape 10. Machinery of Justice 11. Unseen Worlds Epilogue: Alan Turing Decoded Notes and Accreditations Copyright Blue Plaques in Hampton, Maida Vale, Manchester and Wilmslow. At Bletchley Park, where Alan Turing did the work for which he is best remembered, there is no plaque but a museum exhibition. INTRODUCTION ALAN TURING is now a household name, and in Britain he is a national hero. There are several biographies, a handful of documentaries, one Hollywood feature film, countless articles, plays, poems, statues and other tributes, and a blue plaque in almost every town where he lived or worked. One place which has no blue plaque is Bletchley Park, but there is an entire museum exhibition devoted to him there. We all have our personal image of Alan Turing, and it is easy to imagine him as a solitary, asocial genius who periodically presented the world with stunning new ideas, which sprang unaided and fully formed from his brain. The secrecy which surrounded the story of Bletchley Park after World War Two may in part be responsible for the commonly held view of Alan Turing. For many years the codebreakers were permitted only to discuss the goings-on there in general, anecdotal terms, without revealing any of the technicalities of their work. So the easiest things to discuss were the personalities, and this made good copy: eccentric boffins busted the Nazi machine.
    [Show full text]
  • Was the Manchester Baby Conceived at Bletchley Park?
    Was the Manchester Baby conceived at Bletchley Park? David Anderson1 School of Computing, University of Portsmouth, Portsmouth, PO1 3HE, UK This paper is based on a talk given at the Turing 2004 conference held at the University of Manchester on the 5th June 2004. It is published by the British Computer Society on http://www.bcs.org/ewics. It was submitted in December 2005; final corrections were made and references added for publication in November 2007. Preamble In what follows, I look, in a very general way, at a particularly interesting half century, in the history of computation. The central purpose will be to throw light on how computing activity at the University of Manchester developed in the immediate post-war years and, in the context of this conference, to situate Alan Turing in the Manchester landscape. One of the main methodological premises on which I will depend is that the history of technology is, at heart, the history of people. No historically-sophisticated understanding of the development of the computer is possible in the absence of an appreciation of the background, motivation and aspirations of the principal actors. The life and work of Alan Turing is the central focus of this conference but, in the Manchester context, it is also important that attention be paid to F.C. Williams, T. Kilburn and M.H.A. Newman. The Origins of Computing in Pre-war Cambridge David Hilbert's talk at the Sorbonne on the morning of the 8th August 1900 in which he proposed twenty-three "future problems", effectively set the agenda for mathematics research in the 20th century.
    [Show full text]
  • Tommy Flowers - Wikipedia
    7/2/2019 Tommy Flowers - Wikipedia Tommy Flowers Thomas Harold Flowers, BSc, DSc,[1] MBE (22 December 1905 – 28 October 1998) Thomas Harold Flowers was an English engineer with the British Post Office. During World War II, Flowers MBE designed and built Colossus, the world's first programmable electronic computer, to help solve encrypted German messages. Contents Early life World War II Post-war work and retirement See also References Bibliography External links Tommy Flowers – possibly taken Early life around the time he was at Bletchley Flowers was born at 160 Abbott Road, Poplar in London's East End on 22 December Park 1905, the son of a bricklayer.[2] Whilst undertaking an apprenticeship in mechanical Born 22 December 1905 engineering at the Royal Arsenal, Woolwich, he took evening classes at the University of Poplar, London, London to earn a degree in electrical engineering.[2] In 1926, he joined the England telecommunications branch of the General Post Office (GPO), moving to work at the Died 28 October 1998 research station at Dollis Hill in north-west London in 1930. In 1935, he married Eileen (aged 92) Margaret Green and the couple later had two children, John and Kenneth.[2] Mill Hill, London, From 1935 onward, he explored the use of electronics for telephone exchanges and by England 1939, he was convinced that an all-electronic system was possible. A background in Nationality English switching electronics would prove crucial for his computer designs. Occupation Engineer Title Mr World War II Spouse(s) Eileen Margaret Flowers' first contact with wartime codebreaking came in February 1941 when his Green director, W.
    [Show full text]
  • Jewel Theatre Audience Guide Addendum: Alan Turing Biography
    Jewel Theatre Audience Guide Addendum: Alan Turing Biography directed by Kirsten Brandt by Susan Myer Silton, Dramaturg © 2019 ALAN TURING The outline of the following overview of Turing’s life is largely based on his biography on Alchetron.com (https://alchetron.com/Alan-Turing), a “social encyclopedia” developed by Alchetron Technologies. It has been embellished with additional information from sources such as Andrew Hodges’ books, Alan Turing: The Enigma (1983) and Turing (1997) as well as his website, https://www.turing.org.uk. The following books have also provided additional information: Prof: Alan Turing Decoded (2015) by Dermot Turing, who is Alan’s nephew by way of his only sibling, John; The Turing Guide by B. Jack Copeland, Jonathan Bowen, Mark Sprevak, and Robin Wilson (2017); and Alan M. Turing, written by his mother, Sara, shortly after he died. The latter was republished in 2012 as Alan M. Turing – Centenary Edition with an Afterword entitled “My Brother Alan” by John Turing. The essay was added when it was discovered among John’s writings following his death. The republication also includes a new Foreword by Martin Davis, an American mathematician known for his model of post-Turing machines. Extended biographies of Christopher Morcom, Dillwyn Knox, Joan Clarke (the character of Pat Green in the play) and Sara Turing, which are provided as Addendums to this Guide, provide additional information about Alan. Beginnings Alan Mathison Turing was an English computer scientist, mathematician, logician, cryptanalyst, philosopher and theoretical biologist. He was born in a nursing home in Maida Vale, a tony residential district of London, England on June 23, 1912.
    [Show full text]
  • The UK Secret State and the History of Computing
    Putting the spooks back in? The UK secret state and the history of computing email: [email protected] Jon Agar is Professor of Science and Technology Studies at University College London. He is the author of The Government Machine (2003), Constant Touch: a Global History of the Mobile Phone (2003) and Science in the Twentieth Century and Beyond (2012). Mailing address: STS, UCL, Gower Street, London, WC1E 6BT Writing of Cold War historiography, Richard Aldrich, the historian of GCHQ, agrees with Christopher Andrew, the historian of MI5: shortly after VJ-Day, something rather odd happens. In the words of [Andrew], the world’s leading intelligence historian, we are confronted with the sudden disappearance of signals intelligence from the historical landscape. This is an extraordinary omission which, according to Andrew, has “seriously distorted the study of the Cold War”1 The same can be said for the way that the near absence of branches of the secret state has distorted the historiography of post-war computing. This lacuna has been pointed out recently for the American case by Paul Ceruzzi. Historians, he felt, have ‘done a terrible job, because they have failed to chronicle the critical work done by the NSA [National Signals Agency] and other related agencies in computing.2 While he identified a few notable exceptions, I think the point stands: the work that has been done is patchy, and the overall significance of the secret state has not yet been assessed. In this paper I survey the UK case, piecing together what we might reliably know.
    [Show full text]