DOCSLIB.ORG

The University of Chicago a Study of the Evaporative

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
The University of Chicago a Study of the Evaporative THE UNIVERSITY OF CHICAGO A STUDY OF THE EVAPORATIVE DEPOSITION PROCESS: PIPES AND TRUNCATED TRANSPORT DYNAMICS A DISSERTATION SUBMITTED TO THE FACULTY OF THE DIVISION OF THE PHYSICAL SCIENCES IN CANDIDACY FOR THE DEGREE OF DOCTOR OF PHILOSOPHY DEPARTMENT OF PHYSICS BY RUI ZHENG CHICAGO, ILLINOIS SEPTEMBER 2007 Copyright °c 2007 by Rui Zheng All rights reserved To people from whom I have learned and bene¯ted; To the University of Chicago where I rediscovered myself. ABSTRACT We consider contact line deposition and pattern formation of a pinned evaporating thin drop. We identify and focus on the transport dynamics truncated by the maximal concentration, proposed by Dupont [1], as the single deposition mechanism. The trun- cated process, formalized as \pipe models", admits a characteristic moving shock front solution that has a robust functional form and depends only on local conditions. By applying the models, we solve the deposition process and describe the deposit density pro¯le in di®erent asymptotic regimes. In particular, near the contact line the density pro¯le follows a scaling law that is proportional to the square root of the concentration ratio, and the maximal deposit density/thickness occurs at about 2=3 of the total dry- ing time for uniform evaporation and 1=2 for di®usion-controlled evaporation. Away from the contact line, we for the ¯rst time identify the power-law decay of the deposit pro¯le with respect to the radial distance. In comparison, our work is consistent with and extends previous results [7]. We also predict features of the depinning process and multiple-ring patterns within Dupont model, and our predictions are consistent with empirical evidence. PACS. 47.55.Dz Drops and Bubbles - 68.03.Fg Evaporation and condensation - 81.15.- z Methods of deposition of ¯lms and coatings; ¯lm growth and epitaxy iv ACKNOWLEDGMENTS This work is the presentation of one of several research projects pursued under the supervision of Professor Thomas A. Witten at the Department of Physics, University of Chicago. It also serves to summarize my education experience and intellectual development at the University. Tom has been a great mentor to me in both sciences and wisdoms of everyday life. Many pursuits would not be accomplished, nor would any success be achieved, without his constant guidance, encouragement, and understanding. I am deeply a®ected by his unrelenting passion for the truth of nature, the joy of life, and the purity of mind. At the same time, I owe a lot to the close cooperation and communications among Tom's research group, which includes these former and current members: Vladimir Belyi, Jungren Huang, Nathan Krapf, Tao Liang, Yuri Popov, and Quan Zhang. I have been fortunate enough to enjoy the most intense intellectualism that the Uni- versity of Chicago has to o®er. I was able to listen to and learn from many great minds from various disciplines across the University community, and they helped to hone my wits and enrich my life. I thus pay my sincerest gratitude to Gary Becker, Peter Constantin, Todd Dupont, Peter Freund, Ilya Gruzberg, Lars Hansen, Je®rey Harvey, James Heckman, Heinrich Jaeger, Leo Kadano®, David Kutasov, Gene Mazenko, Kevin Murphy, Roger Myerson, Raghavan Narasimhan, Raghuram Rajan, Lenya Ryzhik, Thomas Sargent, Mary Silber, Robert Townsend, Shankar Venkataramani, Carlos Wag- ner, and Paul Wiegmann. I also like to thank Van Bistrow, Mark Chantell, Kate Cleary, Charlotte Coles, Joseph O'Gallagher, Stuart Gazes, Qiti Guo, and especially Nobuko McNeill for their support and help at the department. There are a lot of former and current members of the department who helped v vi to make my life more enjoyable. They are Ruoyu Bao, Xiang Cheng, Ishai Ben- Dov, Seung-Yeop Lee, Zumin Luo, Arjun Menon, Xiaohui Qu, Maria Ratajczak, Ilia Rushkin, Jing Shu, Xinliang Xu, Nataliya Yufa, Xibo Zhang, Yi Zheng, and Ling-Nan Zou. Finally I shall thank my closest friends Jingshi Hu and Ming Zhang. Jingshi, Ming, and I have spent the past ten years together in pursuit of physics. In this great instance of convergence of lives, we di®er and we compete, but most importantly we have learned to share. TABLE OF CONTENTS ABSTRACT . iv ACKNOWLEDGMENTS . v LIST OF FIGURES . ix CHAPTER 1 INTRODUCTION . 1 2 PIPE MODELS . 8 2.1 A Uniform Pipe . 8 2.2 A More Realistic Pipe: Non-Singular Case . 10 2.3 A More Realistic Pipe: Singular Case . 15 2.4 Truncated Transport Dynamics and the Shock Front . 16 3 EVAPORATIVE DEPOSITION WITH UNIFORM EVAPORATION . 20 3.1 Review of Evaporating Thin Drop Hydrodynamics . 21 3.2 Solute Volume Concentration Pro¯le . 24 3.2.1 Concentration Pro¯le in the Transport Region . 24 3.2.2 Concentration Pro¯le in the Deposition Region . 27 3.3 The Shock Front . 29 4 DEPOSIT DENSITY PROFILE WITH UNIFORM EVAPORATION . 32 4.1 Areal Density . 32 4.2 Asymptotic Time-Independent Deposition . 35 4.2.1 Deposition at Initial Drying Stage . 35 4.2.2 Deposition in Time-Independent Geometry . 37 4.3 Density Pro¯le in Spatial Asymptotic Regimes . 39 4.3.1 Near the Contact Line . 39 4.3.2 Toward the Center of the Drop . 43 5 DEPOSIT PROPERTIES WITH DIFFUSION-CONTROLLED EVAPORA- TION . 45 5.1 Hydrodynamics and Concentration Pro¯le . 45 5.2 Deposit Density Pro¯le . 47 6 COMPARISON WITH POPOV'S MODEL . 52 6.1 Thickness Pro¯le . 52 6.2 Asymptotic Deposit Properties . 55 vii viii 7 COMMENTS ON DEPINNING AND MULTIPLE-RING PATTERNS . 58 7.1 Depinning Con¯guration . 58 7.2 Formation of Multiple-Ring Patterns . 61 8 DISCUSSION . 66 8.1 Experimental Aspects of the Model . 66 8.2 Generalizations of the Model . 68 9 CONCLUSION . 71 APPENDIX A DIRECT DERIVATION OF THE SHOCK FRONT VELOCITY . 73 LIST OF FIGURES 1.1 Photographs of evaporative deposit patterns . 2 1.2 Time evolution of a pinned evaporating drop . 4 1.3 Numerical simulation of a ring-like deposit pattern . 5 1.4 Numerical results for the areal density pro¯le . 6 2.1 Sketch of a uniform pipe . 9 2.2 Sketch of a real pipe . 11 2.3 Sketch of the truncated dynamics solution . 18 3.1 Con¯guration of an evaporating thin drop . 21 3.2 Sketch of the de¯nition of m(r; t) ..................... 24 3.3 Volume concentration pro¯le in the transport region . 26 3.4 Shock front versus virtual front . 31 3.5 Time evolutions of the two fronts . 31 4.1 Areal density pro¯le . 33 4.2 Aeal density growth dynamics . 34 4.3 Sketch of a time-independent geometry . 38 4.4 Concentration pro¯le in a time-independent geometry . 39 4.5 Scaling property of the areal density pro¯le for small ±0 . 42 4.6 Scaling property of the areal density growth dynamics for small ±0 . 43 5.1 Deposition pro¯le with di®usion-controlled evaporation . 48 5.2 Deposition growth dynamics with di®usion-controlled evaporation . 48 6.1 Areal density pro¯le versus thickness pro¯le . 54 7.1 Photographs of multiple-ring patterns in Deegan's experiments . 64 A.1 Sketch of the de¯nition of M0 and Mt ................... 74 ix CHAPTER 1 INTRODUCTION Evaporative contact line deposition, also known as the \co®ee-drop e®ect", has been the subject of several recent papers [2, 3, 4, 5, 6, 7]. The physical problem originates from a simple phenomenon of everyday life: when a drop containing a solute such as co®ee dries on a surface, the solute is driven to the contact line and forms a characteristic ring pattern (Fig. 1.1). The basic mechanism behind the phenomenon is now well understood [2]: the drying drop is pinned at the contact line so that there must be an outward capillary flow to replace the liquid evaporating at the edge, and this flow carries solute particles to the contact line where the deposit is formed. This simple phenomenon is important in many scienti¯c and industrial applications [8, 9, 10, 11, 12, 13, 14]. The evaporation mechanism can create very ¯ne lines of deposit in a robust way that requires no explicit forming. It can be used to concentrate material strongly in a controllable way. It also creates capillary flow patterns which are useful for processing polyatomic solutes like DNA [15, 16, 17]. The deposition process and the resulting patterns are a®ected by various physical and chemical conditions. The wetting property of the substrate and surface roughness a®ect the geometry of an evaporating drop [18, 19]. Also, within the drop there can be a convective flow induced by gradient in temperature, surfactant concentration, or surface tension [20, 21, 22, 23], and it can lead to very complicated, even fractal- like, deposit patterns. Furthermore, some mechanisms, such as contact line depinning [5, 24], are still not clear, and there are no satisfactory explanations for multiple-ring deposit patterns [25, 26]. Several models have been established under the common assumptions of slow evapo- ration and creeping flow so that quasi-equilibrium dynamics is warranted: the dynamics 1 2 Figure 1.1: Evaporative deposit patterns. Left: photograph of a co®ee stain. Right: a video micrograph of one-micron polystyrene spheres migrating toward the contact line in evaporating water. (Courtesy Robert Deegan) is determined by the time evolution of the equilibrium properties of the evaporating system. These models use di®erent conditions and assumptions on such properties as geometry, evaporation pro¯le, and deposition criteria. In addition to circular thin drop, there have been studies on contact line deposition in an angular region [27, 28, 29], where the nontrivial geometry at the tip of the angle induces a crossover in deposit properties.
Load more

Recommended publications
  • The Existentialism of Martin Buber and Implications for Education
    This dissertation has been microfilmed exactly as received 69-4919 KINER, Edward David, 1939- THE EXISTENTIALISM OF MARTIN BUBER AND IMPLICATIONS FOR EDUCATION. The Ohio State University, Ph.D., 1968 Education, general University Microfilms, Inc., Ann Arbor, Michigan THE EXISTENTIALISM OF MARTIN BUBER AND IMPLICATIONS FOR EDUCATION DISSERTATION Presented in Partial Fulfillment of the Requirements for Degree Doctor of Philosophy in the Graduate School of The Ohio State University By Edward David Kiner, B.A., M.A. ####*### The Ohio State University 1968 Approved by Adviser College of Education This thesis is dedicated to significant others, to warm, vital, concerned people Who have meant much to me and have helped me achieve my self, To people whose lives and beings have manifested "glimpses" of the Eternal Thou, To my wife, Sharyn, and my children, Seth and Debra. VITA February 14* 1939 Born - Cleveland, Ohio 1961......... B.A. Western Reserve University April, 1965..... M.A. Hebrew Union College Jewish Institute of Religion June, 1965...... Ordained a Rabbi 1965-1968........ Assistant Rabbi, Temple Israel, Columbus, Ohio 1967-1968...... Director of Religious Education, Columbus, Ohio FIELDS OF STUDY Major Field: Philosophy of Education Studies in Philosophy of Education, Dr. Everett J. Kircher Studies in Curriculum, Dr. Alexander Frazier Studies in Philosophy, Dr. Marvin Fox ill TABLE OF CONTENTS Page DEDICATION............................................. ii VITA ................................................... iii INTRODUCTION............................ 1 Chapter I. AN INTRODUCTION TO MARTIN BUBER'S THOUGHT....... 6 Philosophical Anthropology I And Thou Martin Buber and Hasidism Buber and Existentialism Conclusion II. EPISTEMOLOGY . 30 Truth Past and Present I-It Knowledge Thinking Philosophy I-Thou Knowledge Complemented by I-It Living Truth Buber as an Ebdstentialist-Intuitionist Implications for Education A Major Problem Education, Inclusion, and the Problem of Criterion Conclusion III.
    [Show full text]
  • Mass Gaps and Braneworlds∗
    Journal of Physics A: Mathematical and Theoretical J. Phys. A: Math. Theor. 53 (2020) 204002 (13pp) https://doi.org/10.1088/1751-8121/ab83ca Mass gaps and braneworlds∗ K S Stelle The Blackett Laboratory, Imperial College London Prince Consort Road London SW7 2AZ, United Kingdom E-mail: [email protected] Received 13 February 2020, revised 24 March 2020 Accepted for publication 26 March 2020 Published 29 April 2020 Abstract Remembering the foundational contributions of Peter Freund to supergravity, and especially to the problems of dimensional compactication, reduction is considered with a non-compact space transverse to the lower dimensional the- ory. The known problem of a continuum of Kaluza–Klein states is avoided here by the occurrence of a mass gap between a single normalizable zero- eigenvalue transverse wavefunction and the edge of the transverse state con- tinuum. This style of reduction does not yield a formally consistent truncation to the lower dimensional theory, so developing the lower-dimensional effective theory requires integrating out the Kaluza–Klein states lying above the mass gap. Keywords: mass gap, effective theory, dimensional reduction, supergravity (Some gures may appear in colour only in the online journal) 1. Memories of Peter Freund It is with great fondness that I think back to all the various interactions that I had with Peter Freund throughout my career. Of course, there are the many shared interests in physics, espe- cially in supersymmetry, nonabelian gauge theories of all sorts, dimensional reduction and string theory. But there are also the episodes, and especially the story telling about episodes, at which Peter was a world master.
    [Show full text]
  • Mass Gaps and Braneworlds--In Memory of Peter Freund
    Mass gaps and braneworlds In Memory of Peter Freund K.S. Stelle1 The Blackett Laboratory, Imperial College London Prince Consort Road, London SW7 2AZ Abstract Remembering the foundational contributions of Peter Freund to supergravity, and es- pecially to the problems of dimensional compactification, reduction is considered with a non-compact space transverse to the lower dimensional theory. The known problem of a continuum of Kaluza-Klein states is avoided here by the occurrence of a mass gap between a single normalizable zero-eigenvalue transverse wavefunction and the edge of the transverse state continuum. This style of reduction does not yield a formally consistent truncation to the lower dimensional theory, so developing the lower-dimensional effective theory requires integrating out the Kaluza-Klein states lying above the mass gap. Memories of Peter Freund It is with great fondness that I think back to all the various interactions that I had with Peter Freund throughout my career. Of course, there are the many shared interests in physics, especially in supersymmetry, nonabelian gauge theories of all sorts, dimensional reduction and string theory. But there are also the episodes, and especially the story telling about episodes, at which Peter was a world master. One could not say that Peter was generally softly spoken. One of my earliest memories of Peter was at an Institute for Theoretical Physics workshop at the University of California at Santa Barbara back in 1986. Peter was giving a seminar, and, as usual, electronic amplification was hardly needed for him. However, one of our senior colleagues (who shall remain nameless) was sitting in arXiv:2004.00965v1 [hep-th] 2 Apr 2020 the front row and was actually managing to sleep during Peter's seminar.
    [Show full text]
  • Arxiv:2008.11225V2 [Hep-Th] 8 Dec 2020 Many Contributions to This Special Issue Are Devoted to Gravity, String Theory Or Higher Dimensions [9–24]
    A Passion for Theoretical Physics: a special issue in memory of Peter G O Freund Jeffrey A Harvey,∗ Emil J Martinec∗ and Rafael I Nepomechie† December 9, 2020 Abstract This is a preface to A Passion for Theoretical Physics, a special issue collection of articles published in J. Phys. A in memory of Peter G O Freund. We dedicate this special issue to the memory of our esteemed colleague, inspiring teacher and cherished friend, Peter Freund (figure 1). Peter George Oliver Freund was born on 7 September 1936 in Timi¸soara,Romania. He ob- tained his PhD under the supervision of Walter Thirring at the University of Vienna in 1960. He came to the University of Chicago in 1963, where he re- mained throughout his career. He passed away on 6 March 2018. Peter's early influential work [1] proposed what became known as the Freund- Harari conjecture, whose far-reaching impact is discussed in the contribution to this special issue by Veneziano [2], see also the review by Peter himself [3]. Dual resonance models (which were ultimately understood to be string theories) ap- peared soon afterwards, and Peter was among the few theorists at that time who took seriously the extra dimensions required for their consistency. Indeed, extra dimensions figured prominently in much of Peter's subsequent work, including the Cho-Freund paper [4] that helped launch a renaissance in Kaluza-Klein the- ories, the Freund-Rubin solution [5] that has played an important role in the AdS/CFT correspondence, his Kaluza-Klein cosmological solutions [6], and his work [7] that presaged the heterotic string.
    [Show full text]
  • M5-Brane Amplitudes Is Through Spinor-Helicity Coordinates Λia [13]
    CALT-TH-2020-001 M5-Brane Amplitudes John H. Schwarz1 Walter Burke Institute for Theoretical Physics California Institute of Technology 452-48 Pasadena, CA 91125, USA Abstract The dynamics of a probe M5-brane, embedded as a hypersurface in eleven- dimensional Minkowski spacetime, is described by a six-dimensional world-volume theory. This theory has a variety of interesting symmetries some of which are obscure in the Lagrangian formulation of the theory. However, as summarized in this review, an alternative approach is to construct all of its on-shell tree-level scattering amplitudes. This enables understanding all of the symmetries in a satisfying way. This work is dedicated to the memory of Peter Freund. arXiv:2001.03793v2 [hep-th] 23 Jan 2020 [email protected] 1 Introduction I am pleased to have an opportunity to contribute to this volume in memory of a great physicist, my good friend Peter Freund. We never collaborated, but I often enjoyed dis- cussing physics with Peter, and I admired his research. Reading his 2007 autobiographical reminiscences, aptly entitled A Passion for Discovery, I learned about Peter’s courage as a student activist in Romania, where in 1956 he faced a row of tanks that were aimed at him and his friends. It was fortunate for him, and the future of physics, that the tanks did not fire and that he was able to make his way to the United States. As it happens, my father was born in a nearby town in Romania that belonged to Hungary when he was there. The border was moved after the first world war.
    [Show full text]
  • Report for the Academic Years 1987-88 and 1988-89
    Institute /or ADVANCED STUDY REPORT FOR THE ACADEMIC YEARS 1987-88 AND 1988-89 PRINCETON • NEW JERSEY nijiUfi.CAL ?""l::r"- £90"^ jr^^VTE LIBriARlf THE !f^;STiTUTE FQll AC -.MiEO STUDY PR1NCE70M, FmEW JEfiGcV 08540 AS3G TABLE OF CONTENTS 7 FOUNDERS, TRUSTEES AND OFFICERS OF THE BOARD AND OF THE CORPORATION 10 • OFFICERS OF THE ADMINISTRATION AND PROFESSOR AT LARGE 1 1 REPORT OF THE CHAIRMAN 14 REPORT OF THE DIRECTOR 1 ACKNOWLEDGMENTS 19 • FINANCIAL STATEMENTS AND INDEPENDENT AUDITORS' REPORT 32 REPORT OF THE SCHOOL OF HISTORICAL STUDIES ACADEMIC ACTIVITIES OF THE FACULTY MEMBERS, VISITORS AND RESEARCH STAFF 41 • REPORT OF THE SCHOOL OF MATHEMATICS ACADEMIC ACTIVITIES OF THE SCHOOL MEMBERS, VISITORS AND RESEARCH STAFF 51 REPORT OF THE SCHOOL OF NATURAL SCIENCES ACADEMIC ACTIVITIES OF THE FACULTY MEMBERS, VISITORS AND RESEARCH STAFF 58 • REPORT OF THE SCHOOL OF SOCIAL SCIENCE ACADEMIC ACTIVITIES OF THE SCHOOL AND ITS FACULTY MEMBERS, VISITORS AND RESEARCH STAFF 64 • REPORT OF THE INSTITUTE LIBRARIES 66 • RECORD OF INSTITUTE EVENTS IN THE ACADEMIC YEAR 1987 - 1988 86 • RECORD OF INSTITUTE EVENTS IN THE ACADEMIC YEAR 1988 - 1989 f:i'S^o FOUNDERS, TRUSTEES AND OFFICERS OF THE BOARD AND OF THE CORPORATION Foiifidcrs CAROLINE BAMBERGER FULD LOUIS BAMBERGER The Board of Trustees [1987-1989] MARELLA AGNELLI Turin, Italy [1988- ] THORNTON F. BRADSHAW New York, New York [deceased December 6, 1988] CHARLES L. BROWN Princeton, New Jersey FLETCHER L. BYROM Carefree, Arizona GLADYS K. DELMAS New York, New York [ -1988] MICHAEL V. FORRESTAL New York, New York [deceased January 11,1 989] MARVIN L. GOLDBERGER Director Institute for Advanced Study, Princeton, NewJersey VARTAN GREGORIAN President New York Public Library, New York, New York WILFRIED GUTH Chairman of the Supervisory Board Deutsche Bank AG, Frankfurt, Federal Republic of Germany RALPH E.
    [Show full text]
  • Peter George Oliver Freund
    PETER GEORGE OLIVER FREUND (9 septembrie 1936, Timişoara – 6 martie 2018, Chicago) Fizician, profesor emeritus în fizică teoretică la Universitatea din Chicago. Eseist şi scriitor. S-a născut în Timişoara, într-o familie înstărită, cu strămoşi de la inceputul secolului al XIX-lea, înmormântați în cimitirul evreilor. Tatăl, Joseph, era medic, iar mama, Rozsi, a cărei familie era proprietara unui magazin mare de textile, era cântăreață de operă. Familia locuia în centrul oraşului, în palatul Färber, între Palatul Llyod şi Palatul Merbl. Joseph Freund era proprietarul şi directorul unui Sanatoriu, cunoscut sub numele Sanatoriul Freund, unde în timpul anilor războiului evreii din oraş erau îngrijiți. Una din măsurile anti-evreieşti interzicea evreilor sa fie tratați de medici ne-evrei, iar medicii evrei nu aveau permisiunea sa trateze bolnavi ne-evrei. Clădirea spitalului a fost CNR-izată, adică expropriată. Numeroşi membri ai familiei au fost asasinați la Auschwitz, iar un unchi, Pavel a fost deportat în Transnistria, la Vapnyarka. Un alt unchi, Emeric (Imre) Freund, era jucător de polo la cluul I.L.S.A. şi a devenit antrenor de înot al echipei naţionale a României. După studii la Universitatea Politehnica Timişoara, Peter Freund a emigrat în 1959 din Romania şi s-a stabilit timp de câțiva ani la Viena, unde a obținut în anul 1960 doctoratul în fizică teoretică la fizicianul de renume Walter Thirring la Universitatea din Viena. Din 1965 este la Universitatea din Chicago. În prezent este Professor Emeritus, Departamentul de Fizică, Institutul Enrico Fermi, Universitate. Locuieşte la Chicago împreună cu soția, Lucy, psiholoagă. Au două fiice (Pauline, avocată şi Caroline, economistă) şi 5 nepoți.
    [Show full text]
  • Thom Curtright
    Thom Curtright University of Miami Talk presented at BASIC 2019, Saturday, 12 January. ========== Albert De Roeck briefly described the vacuum stability issue in his talk last Tuesday. This brought to mind my 1977 Caltech PhD thesis ... wherein "Renormalization group analysis is used to show the supersymmetric point in the effective coupling constant space is an unstable fixed point for several model gauge theories. The physical significance of this result is discussed in terms of the stability of the semiclassical ground state." This work extended ideas in an earlier paper ... In fact, if you search InSPIRE for title words "vacuum", "stability", and "supersymmetry" before the year 2000, this is the only paper that comes up. My thesis dealt with "toy" models, but I believe the essential idea applies to the standard model as well. Under RG flow in terms of the scalar field expectation value, the effective potential evinces a stable vacuum iff the effective quartic scalar field couplings remain non-negative. For a supersymmetric model this is guaranteed because the quartic scalar couplings are the squares of Yukawa and/or gauge couplings. More Reminiscences about the 20th century Afshordi’stalk on Thursday provided an argument against having very high mass elementary particles, such as would appear along linearly rising Regge trajectories in string theory. Perhaps higher dimensions circumvent his argument. In any case, string theories in higher dimensions yield not only high mass excitations of the string, but in addition, they provide such states in the form of rather exotic rotation group representations – neither totally symmetric nor totally antisymmetric tensors.
    [Show full text]
  • Particle Theory at Chicago in the Late Sixties
    January 2020 Particle Theory at Chicago in the Late Sixties Paul H. Frampton Dipartimento di Matematica e Fisica "Ennio De Giorgi", Universit`adel Salento and INFN-Lecce, Via Arnesano, 73100 Lecce, Italy∗ Abstract As a contribution requested by the editors of a Memorial Volume for Peter G.O. Freund (1936-2018) we recall the lively particle theory group at the Enrico Fermi Institute of the University of Chicago in the late sixties, of which Peter was a mem- orable member. We also discuss a period some twenty years later when our and Peter's research overlapped on the topic of p-adic strings. In memory of Peter G.O. Freund Submitted to a special issue of Journal of Physics A entitled A passion for theoretical physics: in memory of Peter G.O. Freund. Edited by J. Harvey, E. Martinec and R. Nepomechie. ∗[email protected] 1 Introduction It is a pleasure and an honour to write in memory of Professor Peter G.O. Freund (1936-2018) who spent most of his career, from 1965 to 2018, at the University of Chicago. As can be read elsewhere in this book he had been born and initially educated in Romania then acquired his PhD at the University of Vienna which explains his European sophistication. He had a passion for theoretical physics and inspired many young people, including myself, in their quest to extend human knowledge. 2 Enrico Fermi Institute At the beginning of September 1968, I arrived at the University of Chicago group in the Enrico Fermi Institute for a two-year postdoctoral position having just finished a D.Phil in Oxford.
    [Show full text]
  • May 2012 • Vol
    May 2012 • Vol. 21, No. 5 Fang Lizhi Remembered A PUBLICATION OF THE AMERICAN PHYSICAL SOCIETY see page 6 WWW.APS.ORG/PUBLICATIONS/APSNEWS/INDEX April Meeting Prize and Award Recipients APS Unveils Five-year Strategic Plan After a year of work by its and rolled out to the leaders of outlines goals to make the phys- leadership, the APS strategic plan APS units at the unit convocation ics community thrive. First and for 2013 through 2017 has been in April. “The overall goals are foremost, the Society aims to completed and is being circulated to better serve the members, the keep its journals and meetings to the membership. The plan sets physics community and society,” as prime sources of cutting-edge forth a series of goals for the So- Kirby said. physics research. In addition, the ciety over the next half-decade. Finding ways to better serve Society will continue to advocate “The value of a strategic plan the members includes improv- for physics to policy makers, and is that it articulates a common vi- ing communication between the continue to promote physics edu- sion for the Society,” said APS Society and its members, involv- cation at all levels. Executive Officer Kate Kirby. ing more international members In order to serve society as a “The process itself involves step- in the Society’s leadership, and whole, APS aims to be the lead- ping back, looking at what we are making the membership itself ing source of information about doing, and identifying possible more diverse and inclusive. physics, and to build support for challenges and new opportunities “It’s important that the physics science amongst the public.
    [Show full text]
  • A Life in Mathematical Science Part I: Growing-Up, Student and Postdoc Years
    A Life in Mathematical Science Part I: Growing-Up, Student and Postdoc Years Nicholas Stephen Manton FRS ∗ Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Wilberforce Road, Cambridge CB3 0WA, England. March 2017 { September 2018 Abstract This memoir has been prepared in response to the Royal Society's request for Fellows to write an autobiography. There is more here of a personal nature than the Royal Society needs, but also a review of my scientific work and recollections about some of the scientists I have met and worked with. ∗email: [email protected] 1 1 Introduction It is interesting to look back on one's life and career, recall some key memories, and try to assess the significance of one's contribution to science. My life has not been very eventful from the public's perspective. I'm little known outside a modest circle of theoretical physicists and some mathematicians, and have not appeared as a scientist on TV. I have hardly ever been interviewed by journalists, except once for Finnish radio when Stephen Hawking was unavailable. But I have had an interesting time in science, and most of my social life revolves around interactions with academic colleagues and graduate students. For over 30 years, family life has been with my wife Anneli Aitta and our son Ben. I am currently 65 and expect to retire in about two years. I would hope to be involved with research beyond retirement, and to keep writing articles and maybe another book. But I have had some health problems recently, so felt that it was a good time to start on this memoir.
    [Show full text]
  • Supersymmetric Yang-Mills Theories: Not Quite the Usual Perspective
    Supersymmetric Yang-Mills Theories: not quite the usual perspective Sudarshan Ananth :, Hermann Nicolai ‹, Chetan Pandey : and Saurabh Pant : :Indian Institute of Science Education and Research Pune 411008, India ˚Max-Planck-Institut f¨ur Gravitationsphysik (Albert-Einstein-Institut) Am M¨uhlenberg 1, 14476 Potsdam, Germany Abstract In this paper, we take up an old thread of development concerning the characterization of supersymmetric theories without any use of anticommuting variables that goes back to one of the authors’ very early work [1]. Our special focus here will be on the formulation of supersymmetric Yang-Mills theories, extending previous results beyond D “ 4 dimensions. This perspective is likely to provide new insights into these theories, and in particular the maximally extended N “ 4 theory. As a new result we re-derive the admissible dimensions for interacting (pure) super-Yang-Mills theories to exist. This article is dedicated to the memory of Peter Freund, amongst many other things an early contributor to supersymmetry, and an author of one of the very first papers on superconformal gauge theories [2]. The final section contains some personal reminiscences of H.N.’s encounters arXiv:2001.02768v2 [hep-th] 12 Mar 2020 with Peter Freund. 1 Introduction and Conventions There is a large literature on supersymmetric Yang-Mills theories (see e.g. [3]), particularly concerning the maximally extended N “ 4 theory in four dimensions, or equivalently, pure super-Yang-Mills theory in D “ 10 [4]. This theory has been proposed to underlie M theory, either via the AdS/CFT correspondence [5], or, in its dimensionally reduced form, the maxi- mally supersymmetric SU(8) matrix model [6, 7].
    [Show full text]