Astrophysics

Interview with Wick Haxton, professor of physics at UC Berkeley. Haxton recounts his childhood in Santa Cruz and his early interests in math and science. He describes his undergraduate education at the newly created UC Santa Cruz where his initial interest was in mathematics before he was given the advice that he did “mathematics like a physicist.” Haxton discusses his graduate work at Stanford where his original intent was to study general relativity before he connected with Dirk Walecka and Bill Donnelly to focus on nuclear theory and dense nuclear matter. He discusses his postdoctoral research at the University of Mainz where he concentrated on photo-pion physics during the early days of chiral perturbation theory, and he explains the opportunities that led to his next appointment at the LAMPF facility at Los Alamos. Haxton emphasizes the excellence of both his colleagues and the computational capacity at the Lab, and he describes his faculty appointment at Purdue and the solar neutrino experiment he contributed to in Colorado. He explains the opportunities that led to him joining the faculty at the University of Washington where the DOE was about to fund the Institute for Nuclear Theory. Haxton explains the “breakup” between nuclear theory and particle theory and how the INT addressed that. Haxton discusses the opportunities afforded at the INT to engage in nuclear astrophysics and he explains the rise and fall of the Homestake DUSEL project. He explains his decision to go emeritus at UW and to join the faculty at UC Berkeley and to be dual hatted at the Berkeley Lab, and he describes his tenure as department chair. At the end of the interview, Haxton describes his current work organizing the new Physics Frontier Center and the challenges presented by the pandemic, and he credits his formative time as Los Alamos for the diverse research agenda he has pursued throughout his career.

Interview with Marcelle Soares-Santos, assistant professor of physics at the University of Michigan. Soares-Santos recounts her childhood in Brazil, her early interests in science, and her graduate work in physics at the University of São Paulo. She describes her graduate visit to Fermilab to study galaxy clusters as a way to map the history of the expanding universe, which formed the basis of her thesis research. Soares-Santos discusses her return to Fermilab as a postdoctoral researcher, where she joined the Dark Energy Survey, and she explains how DES is getting us closer to understanding what dark energy is. She describes Fermilab’s broad-scale transition into astrophysics, and she explains the opportunities that led to her faculty appointment first at Brandeis before moving to Michigan. Soares-Santos discusses her current work in gravitational waves, and she prognosticates on what the discovery of dark energy (or energies) will look like. She shares her perspective on recent efforts to improve diversity and inclusivity in STEM. At the end of the interview, Soares-Santos explains why observation is leading theory in the current work of astrophysics and cosmology and why she is optimistic for fundamental advances in the field.

Interview with Joshua Frieman, head of the Particle Physics Division at Fermilab, and professor of astronomy and astrophysics at the Kavli Institute for Cosmological Physics at the University of Chicago. He recounts his childhood in Princeton as the son of a physicist and his decision to attend Stanford as an undergraduate, where his interests in cosmology developed. Frieman explains that his options for graduate research in cosmology were narrow and his reasons for going to the University of Washington to work with Jim Bardeen before moving to Chicago to be Michael Turner’s first graduate student. He discusses his interest in approaching cosmology from the perspective of particle theory and his thesis focus on curved space time within a cosmological context. Frieman describes his postdoctoral work at SLAC and his first position at Fermilab in the theory group that Dave Schramm had started. He discusses his work on the Sloan Digital Sky Survey and then the Dark Energy Survey. Frieman explains what might be needed to understand dark energy, he describes his appointment at Chicago, and he explains the origins of the Magellan Telescopes project. He discusses the value of the Aspen summer sessions and his involvement with P5, and explains the value of the 2010 Decadal Survey. At the end of the interview, Frieman surveys the current slate of project at Fermilab and emphasizes the value of incorporating cosmological perspectives to high-energy and particle physics. 

In this interview, David Zierler, Oral Historian for AIP, interviews Joseph Silk, Homewood Research Professor of Physics at Johns Hopkins, Researcher Emeritus at the Institute of Astrophysics in Paris, and Senior Fellow at the Beecroft Institute for Cosmology and Astro-Particle Physics. Silk recounts his childhood in London as the child of working-class parents, and he describes his early interests in math and his acceptance to Cambridge. He discusses the influence of the fluid dynamicist George Batchelor and the gravitational theorist Denis Sciama, and his decision to pursue graduate work at Manchester before enrolling at Harvard for his PhD research under the direction of David Layzer. Silk describes the revolutionary discovery of the cosmic microwave background and some of the observational advances that were driving the young field of cosmology and galaxy formation. He discusses his postdoctoral appointment with Fred Hoyle back at Cambridge and his next research position working with Lyman Spitzer at Princeton, and with Jerry Ostriker on black holes and pulsars. Silk describes the circumstances leading to his first faculty appointment at Berkeley and the excitement surrounding the high red shift universe, the birth of X-ray astronomy, and he describes Berkeley Laboratory’s gradual emphasis on astrophysics over his 30-year career at UC Berkeley. He discusses his long-term research endeavor to verify the prediction of the Big Bang theory and the incredible results of the COBE project. Silk describes his budding interests in particle astrophysics, which he considers a discipline distinct from astronomy, cosmology and astrophysics, and which grew from cosmic inflation. He describes the import and future prospects of supersymmetry, how his namesake contribution “Silk damping” came about, and he conveys his excitement about moon-based telescopes. Silk draws a distinction between understanding the very beginning of the universe (t = 0) and the tiniest fraction of time after that (t = epsilon) and why an understanding quantum gravity will be necessary to make advances in this field. He discusses the current controversy around the Hubble constant, he describes his decision to transfer from Berkeley to Oxford and how this led to his current slate of affiliations, including his appointment at Johns Hopkins. At the end of the interview, Silk discusses his current interests in the moon telescope project and what the legal ramifications of a permanent moon presence might look like and why, in his popular talks, he finds it important to project a sense of awe about the universe.

Interview with Anne Kinney, Deputy Center Director of the NASA Goddard Space Flight Center. Kinney recounts her childhood in Wisconsin and her early interests in science. She describes her undergraduate experience at the University of Wisconsin where she pursued degrees in physics and astronomy. Kinney discusses her time in Denmark at the Niels Bohr Institute before completing her graduate work at NYU relating to the International Ultraviolet Explorer. She explains the opportunities leading to her postdoctoral appointment at the Space Telescope Science Institute in Baltimore where she focused on obtaining optical data and near-infrared data to understand spectral energy distribution for quasars and blazars. Kinney discusses her work on the aberrated Hubble Telescope and her new job at NASA Headquarters where she became head of Origins before she was transferred to Goddard where she became division direct of the Planetary Division. She describes Goddard’s efforts to promote diversity and she describes her subsequent position as chief scientist at Keck Observatory before returning to Washington to join the National Science Foundation to be head of the Directorate for Mathematical and Physical Sciences. Kinney provides a broad view of the NSF budgetary environment, and she explains the circumstances that led her back to NASA to her current work. She describes where Goddard fits into NASA’s overall mission and she explains her interest in promoting NASA in an educational framework to children. At the end of the interview, Kinney conveys her excitement about the James Webb Telescope and why she is committed to ensuring that NASA is a driver behind the broader effort to make astronomy and physics more diverse.

Interview with Tsuneyoshi (Tune) Kamae, Professor Emeritus, both of the University of Tokyo, Department of Physics and of SLAC. Kamae discusses his current work configuring digital devices on science education for the visually impaired, and he recounts his childhood in Himeji and then Osaka, Japan and his early memories of World War II. He describes his undergraduate education at Kyoto University and his developing interest in physics and the opportunity that led to his acceptance at Princeton to work with Val Fitch on the root cause of CP violation. Kamae describes his postdoctoral work at KEK in Japan, where he studied the internal motion of the proton inside the nucleus, and he explains the circumstances that led him to LBL and then SLAC to work on the Time Projection Chamber. He discusses his involvement with the SSC planning and how he became involved in X-ray astronomy. Kamae discusses SLAC’s embrace of astrophysics under the leadership of Burt Richter, and he reflects on some of the cultural differences in physics environments in the United States and Japan. At the end of the interview Kamae shares his hopes for the future of the education program he is developing, and he discusses some of the strategic challenges Japan is facing in light of its demographic trends.

Interview with Elena Aprile, Centennial Professor of Physics at Columbia University. Aprile describes the feeling of just having been elected to the National Academy of Science and she describes how the XENON Dark Matter search has continued despite the pandemic. She explains why so much of physics is devoted to try to understand dark matter and where she sees the interplay of theory and experiment toward that end. Aprile describes why finding dark matter will mean finding new physics beyond the Standard Model, and she recounts her upbringing in Milan and her developing interests in physics during high school. She describes her first visit to CERN when she was a student at the University of Naples and what it was like to meet Carlo Rubbia. Aprile discusses her graduate work at the University of Geneva where she worked on scattering protons to study time violation effects. She explains her interest in the UA1 and UA2 experiments at CERN and her work on noble liquid detectors, her appointment at Harvard, and her first involvement with radiation spectroscopy. Aprile narrates her realization that xenon would be valuable for astrophysics and dark matter specifically, and she describes the origins of the LXeGRIT telescope project. She explains why Gran Sasso was chosen on the site of the XENON experiment and some of the technical and economic challenges in dealing with xenon on the scale required to search for dark matter. Aprile reflects on the difficulties she has faced as a woman in her field, and she describes the competitive value in having the LZ experiment and its search for dark matter. She explains how one goes about searching for dark matter without knowing what dark matter is. At the end of the interview, Aprile imagines what it will mean to find dark matter, what mysteries it will solve, and why she will remain steadfastly cautious before confirming the discovery. 

Interview with Hiranya Peiris, Professor of Astrophysics at University College London and Director of the Oscar Klein Centre and Professor of Cosmo-Particle Physics at Stockholm University. Peiris describes her dual affiliation, she discusses diversity in STEM over the past year, and she surveys the current interplay between theory and observation in her field. She recounts her childhood and family heritage in Sri Lanka and the circumstances that led her family to relocate to the United Kingdom. Peiris describes her interests in math and science the opportunities that led to her enrollment at Cambridge as an undergraduate and a formative experience at JPL in California. She explains her decision to pursue a PhD at Princeton, where she worked with David Spergel on WMAP. Peiris discusses her postdoctoral appointment as a Hubble fellow at the University of Chicago to continue to work on WMAP, and her subsequent work as a Halliday fellow at Cambridge. Peiris discusses her work on the Lyman-alpha forest and her faculty appointment at UCL where cosmology was just coming into maturity. She conveys the excitement as WMAP results were becoming available and her contributions to the search for dark matter. Peiris explains why the LSST project is so significant, what it was like to win the Breakthrough Prize, and the gratitude she feels by having eminent physicists as mentors. At the end of the interview, Peiris emphasizes the importance of following inquiry into the most fundamental questions surrounding gravity and space time, and why Stephen Hawking remains an intellectual inspiration to her.

Interview with Frank Shu, University Professor emeritus at UC Berkeley and UC San Diego, and Founder and CEO of Astron Solutions Corporation. Shu describes his current work on climate mitigation through his company, Astron Solutions Corporation, and he reflects on how his expertise in physics is useful for this endeavor. He recounts his family origins in Wenzhou, China, and their experiences during the Japanese occupation. Shu describes his family’s journey to the United States through Hong Kong and Taiwan, and the opportunities that led to his undergraduate study in physics at MIT. He describes his early interests in gravitational collapse, and he explains his decision to pursue graduate research at Harvard, where he worked on density wave theory of spiral structure under the direction of Max Krook. Shu explains his broader interest in star formation and his work at Stony Brook before taking a faculty position at Berkeley. He describes the “inside out” collapse model and the formative influence of Peter Goldreich. Shu explains how he came to lead Tsing Hua University and his achievements in raising its stature before joining the faculty at San Diego, and he discusses his original interests in climate change research. He describes the Heat Exchanger (HX) Project and how his research on nuclear energy has therapeutic benefits for cancer patients. Shu discusses his patent on sealed carbon fiber reinforced carbon nanotubes and the hurdles that are preventing the widespread adoption of molten salt technology. At the end of the interview, Shu describes the importance of taking multi-pronged approach to climate mitigation and that humanity’s best response at this point is to recognize climate change as an emergency.

Interview with Bruno Coppi, Professor of Physics Emeritus at MIT. Coppi recounts his childhood in Lombardi, Italy. He discusses his early interests in nuclear engineering and his graduate work in Milan on neutron transport theory. He explains the opportunities that led to his postgraduate appointment at the Princeton Plasma Physics Laboratory and his subsequent work at Stanford for his postdoctoral research in collision-less plasma. Coppi discusses his work at the Institute for Advanced Study where he interacted closely with Freeman Dyson, and he explains his decision to join the faculty at MIT where he could work with Bruno Rossi. He describes his collaborations in the Soviet Union with nuclear physicists, and he explains the sequencing of the Alcator program to the Ignitor program. Coppi describes the changes inherent in the AEC’s transformation into the DOE, and he explains the import of the Voyager 2 space mission. He describes his current interest in spontaneously rotating plasma and he reflects on why science is a humbling profession, even for geniuses. At the end of the interview, Coppi explains why the role of angular momentum remains profoundly mysterious, and why he is optimistic that he will continue to make contributions to the understanding of burning plasmas.