String models

Interviewed by
David Zierler
Interview date
Location
Video conference
Abstract

In this interview, David Zierler, Oral Historian for AIP, interviews Gordon Kane, Victor Weisskopf Distinguished Professor of Physics at the University of Michigan. He explains why came to hold a chair in Weisskopf’s honor and he describes his affiliation with the Leinweber Center for Theoretical Physics. Kane recounts his childhood in Minnesota and the opportunities that led to his enrollment in physics at MIT and his graduate work at Illinois to work with J.D. Jackson. He explains that the major topic in particle theory during his graduate work was understanding nucleon scattering and the significance of Geoff Chew’s bootstrap mechanism. Kane talks about his contribution to the discovery of the omega minus at Brookhaven and his research at the Rutherford Lab. He explains his decision to join the faculty at Michigan and his interest in group theory because of the advances made by Murray Gell-Mann. Kane describes the early work in the search for physics beyond the Standard Model, and he explains the value of string theory at the Planck scale. He discusses the possible new physics that would have been discovered at the SSC and why compactified M theory offers a plausible path to moving beyond the Standard Model. Kane explains why string theory is testable and why string theory predicts axions, he offers some possible candidates for dark matter and what compactified M theory offers cosmic inflation. At the end of the interview, Kane discusses his current interests in quark masses and charge leptons, he explains some of the advantages inherent in teaching at a large public university, and he describes why communicating science to popular audiences has always been important to him.

Interviewed by
David Zierler
Interview dates
June 15, July 8, July 29, August 19, September 8, 2020
Location
Video conference
Abstract

Interview with David Gross, Chancellor’s Chair Professor of Physics at University of California in Santa Barbara and a permanent member of the Kavli Institute of Theoretical Physics (KITP). Gross begins by describing his childhood in Arlington, Virginia and his family’s later move to Israel. This led to his decision to enroll at the Hebrew University of Jerusalem for his undergraduate studies in physics and mathematics. Gross recalls his acceptance at Berkeley for his graduate studies, where Geoffrey Chew became his advisor. He explains his early interests in strong interactions, quantum field theory, and S-matrix theory. Gross then describes taking a fellowship at Harvard after completing his PhD, where he recalls his early involvement in string theory. He speaks about his subsequent move to join the faculty at Princeton, as well as his introduction to Frank Wilczek, one of his first graduate students with whom he later shared the Nobel Prize. Gross takes us through the discovery of asymptotic freedom, the development of quantum chromodynamics, and the impact these had on the Standard Model. He discusses his decision to leave Princeton for UCSB, where he focused on growing the KITP and securing funding. Gross describes how his research interests have shifted over the years across topics such as confinement, quantum gravity, and more recently back to string theory. Toward the end of the interview, Gross speaks about his work to develop institutes similar to KITP in other countries, as well as his term as President of the American Physical Society in 2019.

Interviewed by
David Zierler
Interview date
Location
Teleconference
Abstract

In this interview, Andreas Albrecht, Distinguished Professor of Physics and Director of the Center for Quantum Mathematics and Physics (QMAP) at the University of California, Davis, discusses his life and career. Albrecht describes the growth of the department since his arrival, his affiliation with QMAP, and the broader effort to integrate more mathematicians into the field of cosmology. He recounts his childhood in Ithaca as the son of two PhD scientists and family sabbatical visits to Santa Cruz and to the Soviet Union. Albrecht describes his budding interests in physics in high school, his undergraduate experience at Cornell and his early exposure to the ideas of Robert Dicke and Alan Guth. He discusses his graduate work at Penn and the circumstances that led him to become Paul Steinhardt’s mentee in cosmology. Albrecht conveys all of the excitement surrounding inflationary cosmology in the early-mid 1980s and the opportunity that led to his postdoctoral appointment with Steve Weinberg’s group at the University of Texas where he became interested in cosmic strings. He describes his subsequent postdoctoral appointment at Los Alamos where he worked with Wojciech Zurek and where his carpools with Geoffrey West proved to be a formative intellectual experience. Albrecht explains his decision to accept a staff position at Fermilab and the contemporary advances in cosmic strings scaling and why primordial nucleosynthesis was uniquely data-oriented relative to other fields in cosmology. He describes his subsequent faculty position at Imperial College in London and he emphasizes the productive and tight-knit cosmology community across the UK. Albrecht conveys the importance of the cosmic microwave background (CMB) experiments and how his ideas of equilibrium cosmology had changed over time and where the term “Boltzman Brains” originated. He describes how UC Davis was rapidly growing and how the opportunity to build a cosmology group was appealing to him. Albrecht explains the origins of his “arrow of time” concept and why this resonates with the broader public’s interests in the universe. He conveys the existential difficulty, and possible impossibility, of developing a credible theory of the beginning of the universe. Albrecht reflects on the spiritual dimensions of cosmological unknowability and the significance of the anthropic principle, and he discusses his efforts as department chair to enhance diversity in the field. At the end of the interview, Albrecht discusses his current work on decoherence and einselection, and he explains why avoiding prejudices in one’s scientific sensibilities is both singularly difficult and key to unlocking future discovery.    

Interviewed by
David Zierler
Interview date
Location
Video conference
Abstract

n this interview, Stephon Alexander discusses current research into quantum gravity and possible extensions to string theory; work to merge quantum mechanics and general relativity; research into the connection between music and cognitive science; experience as a jazz musician; intersections of philosophy and physics; experience as president of the National Society of Black Physicists (NSBP); challenges and stigmas associated with being a Black academic; growing up in both rural Trinidad and the Bronx; undergraduate experience at Haverford; graduate work at Brown; guidance from Robert Brandenberger into the field of quantum gravity, applying particle physics to astrophysics and cosmology; thesis research on solitons and topological defects and its role in string cosmology and theory; decision to take postdoc at Imperial College London focusing on M-theory and integrating string theory with cosmic inflation; influence of Alan Guth; work on D-brane driven inflation; experience in the underground London music scene; decision to go to SLAC in Stanford and work under Michael Peskin; loop quantum gravity; time as faculty at Penn State; the role and responsibility of the Black academic; recruitment by Brown University; intellectual influence of David Finkelstein; the process of becoming president of NSBP. Toward the end of the interview, Alexander reflects on his books, The Jazz of Physics and Fear of a Black Universe; being an outsider in the field of physics; and revisits his current work on quantum gravity. He emphasizes the importance of in-person collaboration and improvisation. 

Interviewed by
David Zierler
Interview date
Location
Video conference
Abstract

Interview with Geoffrey West, Shannan Distinguished Professor at the Santa Fe Institute. West provides a brief history of SFI as a collaborative idea between Murray Gell-Mann, Phil Anderson, and David Pines, and he explains the funding sources that launched the Institute. He recounts his childhood in England and his family’s Jewishly-observant household. West describes his switch from math to physics as an undergraduate at Cambridge and his interest in becoming involved in the origins of SLAC at Stanford. He discusses Panofsky and the “Monster Accelerator,” and studying fold factors of the triton and helium-3 nuclei under the direction of Leonard Schiff. West describes his subsequent postdoctoral work at Cornell and the formative influence of Ken Wilson, and his next position at Harvard where he pursued research on the quark proton model into a kind of a covariant framework. West explains his decision to join the faculty back at Stanford, he conveys the excitement at SLAC in deep inelastic research, and he provides a backdrop of the work that would become the “November Revolution” in 1974. He describes the importance of meeting Peter Carruthers and his reasons for transferring to the theory group at Los Alamos. West discusses his moral conflict working at a Lab with such close ties to nuclear weapon research, and he credits the Manhattan Project as the intellectual source for the Lab’s multidisciplinary approach. West discusses how the culture at Los Alamos served as a prototype for SFI, and how at that point he had migrated intellectually from high energy physics to string theory, and how both organizations encouraged the kind of multidisciplinary approach that encouraged his interests in biological populations. He describes his tenure as SFI president and his developing interest in sustainability, he prognosticates on what the SFI education model could contribute to post-pandemic higher education, and he explains how the pandemic has influenced his views on the future of cities. At the end of the interview, West describes his current interest in biological lifespans and he reflects on the extent to which is unorthodox career trajectory could serve as a model for scientists who will increasingly work in realms less bounded by strict departmental divisions.

Interviewed by
David Zierler
Interview date
Location
Video conference
Abstract

In this interview, Sheldon Glashow, Professor of Physics Emeritus at Harvard University and Professor of Physics Emeritus at Boston University, reflects on his career and Nobel Prize winning work. He discusses his childhood friendship with Steve Weinberg and his passion for science from a young age. He reflects on his decision to attend Cornell University for undergrad and details the physics curriculum at the time. Glashow describes his time as a graduate student at Harvard University studying under Julian Schwinger. He discusses his time as a post-doc at the Institute for Theoretical Physics in Copenhagen working on the SU(2)XU(1) theory, which would later win him a Nobel prize in 1979. He speaks about working with Murray Gell-Mann while at Caltech and their collaboration on a paper together. Glashow details being hired as a full professor at Harvard University. He discusses his frequent collaboration with Alvaro De Rujula. He discusses the concept of string theory and how it has evolved over the years. He discusses the loss of the superconducting super collider and reflects on where particle and theoretical physics may be today had it been built. Lastly, Glashow reflects on his goals for "Inference: International Review of Science", of which he is the editor-at-large.

Interviewed by
David Zierler
Interview date
Location
Video conference
Abstract

Interview with Mark Trodden, Fay R. and Eugene L. Langberg Professor of Physics, and Co-Director of the Center for Particle Cosmology at the University of Pennsylvania. Trodden describes the overlap between astronomy, astrophysics, and cosmology, and he recounts his working-class upbringing in England. He discusses his undergraduate education at Cambridge, where he focused on mathematics, and he explains his decision to switch to physics for graduate school at Brown, where he worked under the direction of Robert Brandenberger. Trodden describes the impact of the COBE program during this time, and he discusses his work on the microphysics of cosmic strings and topological defects and their effect on baryon asymmetry. He explains his decision to return to Cambridge for his postdoctoral research with Anne Davis and his subsequent postdoctoral appointment at MIT to work with Alan Guth. Trodden discusses his next postdoctoral position at Case Western, which he describes as a tremendously productive period, and he discusses the opportunities that led to his first faculty position at Syracuse. He notes the excellent graduate students he worked with at Syracuse, and he explains what is known and not known with regard to the discovery of the accelerating universe. Trodden describes why the theory of cosmic inflation remains outside the bounds of experimental verification, and he explains the decisions that led to his decision to join the faculty at Penn and his subsequent appointment as chair of the department. He discusses the work that Penn Physics, and STEM in general, needs to do to make diversity and inclusivity more of a top-line agenda, and he describes much of the exciting work his current and former graduate students are involved in. At the end of the interview, Trodden looks to the future and offers ideas on how physicists may ultimately come to understand dark energy and dark matter.

Interviewed by
David Zierler
Interview date
Location
Video conference
Abstract

Interview with Andrei Linde, Harald Trap Friis Professor of Physics at Stanford. This discussion continues from the interview with Linde conducted by Alan Lightman in October 1987. He provides a detailed history on his improvement of Alan Guth’s work on inflation, which Linde dubbed “new inflation” and subsequently “chaotic inflation.” Linde describes the impact of Perestroika on Soviet scientists, and the pressures he felt in preparing for a series of talks in Italy, which contributed to his development of “eternal inflation.” He discusses his formative early communication with American physicists including Lenny Susskind and Norman Coleman, he describes his two-year visit at CERN as the Cold War was winding down, and he explains his decision to accept a faculty appointment at Stanford. Linde describes the alternating feelings of hope and despair in the 1980s regarding the possibility that inflation could be observationally verified. He explains the intellectual origins of self-generating fractals that sprout other inflationary universes and the value of compactification theory, and he explains the cultural relevance of his Russian heritage which compels him to value theoretical notions and not treat them in a throwaway manner that capitalism can encourage. Linde explains how and why multiverses can be testable and he reflects on the obvious philosophical or even spiritual implications of this proposition. He discusses the impact of the discovery of the accelerating universe and dark energy and how WMAP strained the theoretical viability of inflation. Linde explains why many string theorists have moved into investigating theories of quantum information, and at the end of the interview, he reflects on the value of competing theories to inflation and why, ultimately, he wants to see a major convergence of theories so that the origins of the universe are well understood. 

Interviewed by
David Zierler
Interview date
Location
Video conference
Abstract

Interview with Juan Maldacena, Carl P. Feinberg Professor at the Institute for Advanced Study. Maldacena recounts his childhood in Buenos Aires, he discusses his undergraduate education at the University of Buenos Aires and his advanced work in physics at Instituto Balseiro where he had his initial exposure to string theory. He explains his decision to pursue a graduate degree at Princeton where he worked with Curt Callan and where he benefited from Ed Witten’s lectures on dualities in quantum field theory and in string theory. Maldacena describes his thesis research on conformal field theories with boundaries and the significance of Joe Polchinski’s discovery of D-branes, and he conveys the importance of his collaboration with Andy Strominger as a postdoctoral researcher at Rutgers. He describes his paper on AdS/CFT while at Harvard and he explains his work on non-gaussianities and his realization that string theory would be useful for cosmology. Maldacena explains his decision to leave the faculty at Harvard to join the Institute, and he describes his subsequent research on space-time and entanglement, the chaos of black holes and the likelihood that they are rapidly thermalizing systems. He explains the contributions of string theory research as offering physics a model for quantum gravity and for the quantum mechanics of spacetime itself, and he shares his perspective on broader debates about how many researchers should or should not be involved in string theory work. At the end of the interview, Maldacena describes his hope in the future to better understand the interiors of black holes.

Interviewed by
David Zierler
Interview date
Location
Video conference
Abstract

Interview with Henry Tye, professor emeritus of physics at Cornell, and subsequently professor emeritus of physics at Hong Kong University of Science and Technology (HKUST), and currently, Researcher at the Jockey Club Institute for Advanced Study at HKUST. Tye provides a brief history of HKUST, and he offers his views on China’s long-term goals in high energy physics. He recounts his childhood in Hong Kong where his family fled from mainland China during the Communist revolution, and he explains the opportunities that led to his undergraduate admission to Caltech. Tye describes how discussions of the Vietnam War permeated his college experience, and he describes the influence of Gerry Neugebauer on his interest in physics but that cosmology was far from his considerations at that point. He discusses his decision to study at MIT, where Francis Low became his advisor, and how he worked closely with Gabriele Veneziano on the relationship between the Thirring model and bosonic string theory. Tye explains the excitement surrounding the “November Revolution” which was unfolding just as he arrived at the SLAC Theory Group in 1974. He describes the origins of his interests in cosmology, and the source of his collaboration with Alan Guth during his postdoctoral work at Cornell, where he pursued matter-antimatter asymmetry. Tye explains how this collaboration ultimately created the field of inflation and why this addresses fundamental cosmological problems associated with flatness and the horizon. He explains how and why the original theory of inflation was revised by Andrei Linde and Paul Steinhardt, among others, and why he developed a subsequent interest in cosmic superstrings and branes which he recognized would give a perfect model for inflation. Tye describes why he is optimistic that technological advances will make cosmic superstrings a testable proposition, and that collaborations including the Sloan Digital Sky Survey and LIGO/Virgo are positive steps in that direction. He bemoans the dearth of string theorists focused on phenomenological work and why he thinks string theory will solve the quantum gravity problem. Tye describes his decision to join the Cornell faculty, why his notions of a “string landscape” suggest philosophical implications, why the cosmic landscape is central for understanding the wavefunction of the universe, and why both the universe and all multiverses can begin from truly nothing. At the end of the interview, Tye discusses his recent interests on the cosmological constant problem, the KLT relation, and the observations and experiments that are most likely to push cosmology into new and exciting areas of discovery.