Theoretical Physics is fascinating because it not only enables us to gain a deep understanding of our very existence through abstract mathematical models but also branches out to different applications of physics in the real world !
Naveen Yadav, our next pathbreaker, Laser-Plasma Interaction Scientist at Marvel Fusion (Munich, Germany), contributes to the theoretical advancement of the fusion concept, validating it and making it more accurate using numerical simulations.
Naveen talks to Shyam Krishnamurthy from The Interview Portal about his lifelong fascination with physics and fundamental research, along with his penchant for rock climbing and mountaineering !
For students, remember that there is no absolute measure of success; it is sheer will, hard work, and commitment to whatever you do no matter what the circumstances are !
Naveen, can you share your background with our young readers?
I was born and grew up in Karnal (a city in Haryana, India). My mother is a housewife, and my father (now retired) worked as a government employee (an economist for the District Rural Development Organisation). During my schooling years, my father lived in Rewari because of his posting, and he could visit us only once a month; therefore, my mother was responsible for ensuring that we remained committed and focused on our education. I want to share with readers from weak financial backgrounds that most of my early years were spent in a financially weak background. However, as you will see later, your economic background can sometimes slow you down but can only deter you for a short time from reaching your goals.
To describe myself, I am curious by nature; I want to know how things work, and in my quest, I broke many things at home (which was not taken lightly by my mother, given our financial situation). My father had a good collection of books about history, geography, and economics at home, and we spent our spare time scrolling through them. Over time, through his books, I developed a habit of reading.
In 6th class, we were introduced to field hockey, which is very demanding—hours of everyday training in the hot summer and cold winters taught me the value of discipline and commitment. I became too committed to the sport and aimed to represent India. I played in a couple of state tournaments and, at one point, thought about leaving school in favour of a sports institution (my mother vetoed it). In the meantime, at school, I was developing a taste for painting (thanks to our art teacher). Somewhere between the stadium and the painting room was my science teacher (Miss. Anita Sharma), who intensely nourished our scientific aptitude. She encouraged us to ask questions and always went the extra mile to ensure we understood the material in our science books. She used to maintain a separate notebook for self-study where she recorded her readings of higher physics. Once in a while, I could look at them sitting in the front row. I still remember colourful equations scribbled in her impressive handwriting. I firmly believe that scientific equations and drawings have a compelling attraction, and I suggest readers look at them frequently if they want to pursue careers in science.
I admit that neither my mother nor I knew that doing science could be a profession. It was very late in my studies (during my Master’s degree) that I realized that science could be pursued professionally. When we were in 7th or 8th standard, my mother sent us for training in typewriting and shorthand so that we could get jobs in government offices. The delicate financial situation at home dictated her plan, and she thought we could someday earn and then learn. Nevertheless, she was supportive of our education and firmly committed to it.
Any specific activities that have shaped your career in Science?
Night skies caught my imagination. Our village is a desert landscape, and we used to spend around three months there every year. We used to sleep outside in those days, and the fabulous band of light across the sky was my everyday delight. My first contact with any astrophysical object was In the 10th class, where we learned about white dwarfs, neutron stars, and the Chandrasekhar limit, and I was fixated on them. I have a vivid memory of the time when Miss. Anita Sharma explained these objects to us (as much as one could without delving into the bearings of quantum mechanics on the structure of these objects).
At this point in my life, I was split between Hockey, Painting, and Science. However, after I joined a math/physics/chemistry stream in the 11th class, the first two disappeared (although I continued playing hockey until I started college), and science remained. Dr. Prem Singh Thakur was our physics teacher, and he was delighted to teach us, and further solidified my physics background. One should always take advantage of every opportunity to learn from a good teacher, as their words will stay fresh for the rest of your life.
Being born in North India, many consider a career in defense charming and honourable. I was charmed by the profession and considered a career in the defense forces as my calling. After finishing school, I appeared for the National Defense Academy (NDA) entrance exam and qualified for it. I appeared for an interview at the Air Force Selection Board (AFSB), Dehradun. I passed the Pilot Aptitude Battery Test (PABT) but could not make it through the interview. Besides, the folks at AFSB told us that people with spectacles could not be fighter pilots. My spirit was not daunted, and I reappeared for the NDA entrance and subsequently went for an interview at SSB, Bhopal. This time, I made it through the interview, but unfortunately, I failed the medical test (my eyes were too bad to be a combat soldier; according to the rules, myopia above -2.5 diopters is unacceptable). Therefore, by the end of 2003, my dream of joining the defense forces as an officer was crushed. In hindsight, it was okay as I could experience many things that I would have missed in the defense forces, but at that moment, I was sad. Somehow, I lifted my spirits and moved on to study for a Bachelor of Science degree. Things happen for good, but sometimes, we fail to appreciate the opportunities that sometimes come with failures.
Another interest of mine when I was young was making toys from waste materials. I was fascinated with flying objects and would make static models of aeroplanes. I made a small lifting crane using sticks from a broom, a WWII Spitfire from cardboard, a Mig-21 using cardboard with old toy car wheels, and the best was a scale model of SU-30 MKI fighter jets by looking at an image in a newspaper. India was surging ahead in missile and rocket technology, and ISRO was making leaps and bounds despite sanctions imposed on India after the Pokhran test in 1998. My father was very impressed by Dr. A.P.J Kalam, and he bought us a copy of “Wings of Fire” –the autobiography of Dr. Kalam. His journey from being born in a very low-income family in a quiet town in Rameswaram to leading India in space and missile technology is a “tour de force” for everyone to read. One could feel his humbleness despite his achievements. I can say that I found the autobiography of Dr. Kalam inspiring; in some way, he played the role of a mentor whom I never met.
Among extra-curricular activities: Apart from painting and playing hockey, I found “hiking” to be a joyous activity. I was hooked on hiking during my PhD days in Mumbai. We hiked extensively through the Western Ghats around Mumbai. During my 3rd year in Mumbai, I bought a mountain bike, and we cycled around a lot – riding hundreds of kilometers away from Mumbai. I found freedom in biking long distances; riding through unknown places far away in the monsoons was liberating. Once, I biked from Mumbai to Khodad, Pune (where the GMRT, a famous Indian radio observatory, is located), to participate in an observation campaign. We often participated in randonneuring events and went to 100 km, 200 km, and 400 km biking events. In Mumbai, I came across the idea of running “Marathons.” Since childhood, I have found running meditative, and building upon my athletic training; I participated in many half– and full-marathons for the next few years. In Bangalore, as a postdoc, I learned rock climbing. I had a lot of fun bouldering and triad climbing in the hills around Bangalore. In Dec 2016, I attended and finished the Basic Mountaineering Course at the Nehru Institute of Mountaineering in Uttarkashi (Uttarakhand). Overall, I enjoy outdoor activities a lot. I wouldn’t say I like travelling so much, but I like walking or biking long distances. In March 2019, inspired by the fables around Prof. H. M. Antia’s (a computational astrophysicist at TIFR, Mumbai) walking prowess, I walked from Munich to the XIXth Workshop on Nuclear Astrophysics held at the Schloss Ringberg, Tegernsee (Germany). It was a distance of around 70 Kms which I covered in approximately 14 hours by foot with luggage 😉 I have mentioned my outdoor activities to ensure the reader understands that scientists are like “normal” people and not always buried in their books – they also engage in many fun activities. I think it is good to pursue outdoor activities as they are like meditation and help one unwind and destress healthily.
What did you do for graduation/post-graduation?
I studied Physics, Chemistry, and Mathematics for graduation. In hindsight, having a good background in advanced mathematics gives one an advantage in all research fields, be it economics, biology, astrophysics, or computing. Therefore, if you get an opportunity to learn advanced mathematics, take it! Coming back to me, the Government P.G. College in Karnal had an adequate library, which gave me access to many good books. I could explore everything from earth sciences, engineering, and fundamental physics to biology under one roof as if the doors of knowledge had been opened for me. The reader may find the valuation of libraries in my life as surprising. It was because I had no access to the internet or a computer (neither at college nor at home), and libraries were the only way to learn. To this day, I have been visiting libraries regularly, and they always have hidden gems. The computers at our college were only available to those pursuing computer science programs, which I was glad about, as I considered computers a waste of time (I imagined that people played video games on them all the time). One of my mentors at the College was Prof. Mahavir Nain, who got me excused from the classroom as he realized that I was a self-learner and that I would spend my time better in the library exploring the world. He always backed me whenever any Professor would complain about my absence from the classroom. I can not thank him enough.
Around the 1st year of my Bachelor’s degree, I understood that my family’s financial resources were insufficient for further education. I decided to join the Indian Railways as a driver to earn money, buy books, and read them. Fortunately, my maternal aunt was visiting and gave me a good lecture about how “taking a full-time job at 17 could be disastrous over the longer term.” She persuaded me that I should learn to manage with the resources at hand. I heeded the advice and continued with my Bachelor’s degree. As you would read later, within four years of this, my fortunes would improve, and I would get a reasonably handsome national fellowship to follow my dreams.
Another exciting thing I would tell the reader is that in the good old days (from the 1940s to the 1980s), some physics textbook authors used to make a comprehensive list of books on various topics in physics, including books competing with their own. Goldstien’s text on classical mechanics was such a book. It contained an exhaustive listing of books on various branches of physics. Luckily, during graduation, I won many quizzes and essay writing competitions and was allowed to use the award money to acquire a lot of books from the old bookshops on Nai Sarak in Delhi. Although not exceptional in mathematics during my school years, I developed a taste for higher mathematics during college. During my second year at college, I read the book “Differential Equations with Examples and Historical Notes” by George F. Simmons. The book presented short historical essays about famous Mathematicians’ lives and their contributions. Suddenly, mathematics became much more alive to me, and I considered that I should study mathematics even more. I saw a newspaper advertisement for the MTTS program (Mathematics Training and Talent Search Programme ). I was fortunate to be selected for the MTTS base camp at Punjab University (P.U.), Chandigarh. At PU, I learned a lot, made many good friends in the physics group (who told me about the books they were studying), and explored the art of mathematics under the guidance of Prof. S. Kumaresan, Prof. Hans Gill, and Prof. Rajwade. These experiences had a lasting impact on me. During school, I read the book “The Meaning of Relativity” by A. Einstein in the P.U. library. I gave a short talk to the MTTS class about curved spaces and how gravitation is understood as the curvature of space-time. At this point, I learned the importance of mathematics in the physical sciences. These are relatively minor things, but they positively impacted me.
After graduation, I qualified for the entrance exam for a Master’s in Physics at Delhi University and settled in to study physics. At this stage, the world suddenly opened up for me. I was in contact with professors with formidable research careers who were excellent teachers and mentors. One could catch them anytime and discuss one’s doubts in physics or mathematics. Delhi University was a safe area for both women and men, and one could walk to Vice Chancellor’s Park at any time of the day or night. I often caught Prof. Patrick Das Gupta on his walks at 10 PM, and he would be kind enough to answer my questions for hours until he felt too tired to go home. He was an astrophysicist/ cosmologist by profession, so he introduced me to many fascinating astrophysics objects and concepts in cosmology. In the second year, one had to choose a specialization domain – electronics vs more physics. I decided to learn more advanced physics and took Astrophysics and Gravitation as my two specializations. These were fascinating times for us; some of the most profound physical theories were unravelled to our excited minds by people working on them. The Inter-University Centre For Astronomy (IUCAA), Pune, used to run a center at DU (under Prof. T. R. Seshadri), where advanced reference books and computers were made available. I used to spend my nights at the center studying. Even at this late stage of education, my profound ignorance about computers had not disappeared, and I stayed away from computers. The only exception was that I had an email account!
In short, I was driven by my curiosity. I chose my graduation and post-graduation subjects based on my long interest in trying to make sense of the physical world for myself.
What were some of the key influences that led you to such an offbeat, unconventional career in Scientific Research?
After my post-graduation, I secured positions in many research institutions through entrance exams. I appeared for the CSIR-UGC-NET exam and was ranked among the top ten candidates. CSIR offered a much better fellowship for the top three candidates, which was determined after two lengthy interviews. Panels of experts at the National Chemical Laboratory (NCL) in Pune interviewed us. I was among the three candidates awarded the Shyama Prasad Mukherjee Fellowships for physics research that year.
Back in Delhi, with a few months left before the joining date, I developed a taste for economics. My interest in economics rose to the point that I decided that I should not pursue a PhD, but pursue a degree in economics at the Delhi School of Economics. On the other hand, my closest friend, Khsitij, wanted to join the PhD program at IISc, Bangalore. He wanted to work there with Prof. Chandan Das Gupta. I had secured the 1st position in the Joint Astronomy Programme run by RRI (Raman Research Institute), IIA, and IISc. After much thought, I decided to go to Bangalore and join IISc, thinking that I would pursue Economics as a side interest; actually, the main idea was that going to the same institute would also allow Khsitij and me to enjoy doing physics as well (we studied together a lot during my Master’s). Soon after joining IISc, we both realized that we could not pursue side subjects while pursuing a PhD as it is a demanding career. So, we left for Delhi, where I studied Economics for the next few months to face an entrance exam to join a reputed institute. After six months, I was bored, and the urge to study physics never diminished.
At the end of six months, I approached TIFR (where I had secured a seat six months ago through their exam and interview), where Prof. Alak Ray was kind enough to seek my late admission by arguing my case with the natural science committee. He later told me that the natural science committee had no strong reservations as I had obtained close to the top rank during the admission process. In short, I bid farewell to Delhi and my friend Khsitij Verma (who later joined civil services as an IFoS officer) and took a train to Mumbai, where I attended graduate school and wrote a doctoral thesis under the guidance of Prof. Alak Ray.
To answer in short, what made me choose this career was my deep desire to study the mysteries of the Universe. I firmly believed that engaging in scientific research was my life’s purpose. I could spend my days pondering the meaning of life and its origin. I could even contribute to unravelling the cosmic mysteries. Although I was aware that I might not be able to answer these questions myself, however during the process of my doctoral research, I had the opportunity to at least read the views of the greatest minds on these questions and had the privilege of working alongside many curious minds which shaped my thinking process as a scientist and a human being.
I had the privilege of meeting a lot of good people and a lot of good scientists. Each of them played a role in my journey as a scientist. However, my mother ingrained a spirit of hard work and commitment in me. Despite a harsh economic reality at home, she always encouraged us to dream and to have a strong will because she knew that where there is a will, there is a way. Among scientific mentors, there were plenty of well-known scientists at the TIFR, and one could talk and discuss with anyone – in a way, the institute mentors you collectively, so pinpointing a few individuals is already hard.
As I said before, I was computer illiterate when I entered my PhD. I made the first plots on graph paper. My advisor told me that it was time that I start using computers. I found a mentor in my immediate senior, Dr. Sayan Chakraborti. He introduced me to Linux and programming. It reminds me of the saying, “When the student is ready, the teacher will appear.” – Sayan was that teacher to me. Given his encouragement, and looking at the prowess of Prof. H. M. Antia, I soon wrote my first parallel program (it was a single source file Particle-In-Cell code with a visualization server created using PlPlot) within two weeks of mentoring from Sayan and debugging help from Prof. H. M. Antia. When I think about it now, it is an achievement for someone like me who was a computer illiterate a few weeks ago.
Additionally, the SPMF provided 75,000 INR/year as a contingency grant to the fellows so that they could buy research-related material. It was so helpful, as I bought a computer from the grant with a loan from my father, which I later paid back after reimbursement from CSIR. On that personal computer, I played around with various flavors of Linux. I did a “Linux from scratch” project. From someone who was computer illiterate, I soon became a person who fixed machines for many colleagues and helped them with programming. The rest of my grant money was spent on buying books, and I had a massive stockpile, which I had to part with when I left TIFR. To reiterate, if I have to give credit to anyone mentoring me regularly during my doctoral work, it would be Dr. Sayan Chakraborti (my Senior from 2010-2013). Prof. Alak was a nice person. However, he was busy studying and researching genetics (he dreamt of starting his genetics lab close to retirement) or taking sabbaticals at Harvard (U.S.). From him, I learned that one could be critical of any work and still not take it personally. I also learned the value of humbleness from observing him, and he had a reputation for standing up for the rights of students (whenever he felt that they were being ignored). He had a quote from Martin Luther King written on the top right of the blackboard in his office: “Our lives begin to end the day we become silent about things that matter.”
Overall, TIFR had no restrictions on people; they could decide their work and even their PhD topics. Another person who made an impression on me was Prof. Shobo Bhattacharjee. He was a member of my PhD mentoring committee. Each year, he would ask me to write an essay about myself (in the third person role). I would write my plans, accomplishments, weaknesses, and dreams as a scientist – he taught me the value of self-reflection for a scientist (and kept reminding me that no matter your age, you must not stop dreaming). My programming hero was Prof. Antia, who was so good that you could tell him the error in your program (without showing the program to him), and he would tell you where the bug was! If you can find his book “Numerical Methods for Scientists and Engineers.” in a library, I would highly recommend it.
How did you plan the steps to get into the career you wanted?
By now, the reader must have noticed that although I had a general sense of direction, it was when I finished my graduation that I had set a path more concretely. Each interaction, each opportunity, and each year presented me with new goals, motivations, and sometimes a new direction, and I pursued them for a while before readjusting the course. So, nothing dramatic as a turning point 😉 It was a long, enjoyable journey, sometimes tedious, sometimes risky. Still, in the end, I am happy with what I could learn and explore.
I chose to be a physicist because I like the subject and the thrill of solving physics problems – a subject where a limited set of fundamental ideas allows you to understand the physical world, ranging from subatomic to cosmic scales. To emphasize, it would not have been possible had I not been fortunate enough to have some good teachers and a lot of good books in my journey.
At any stage of my career, I would not call it the final destination. My new interests will dictate my next career move, and I could be doing something altogether different. In my previous answers, I have charted how I developed and nurtured my interest in natural sciences, so that part is quite evident. It is as simple as “plan-execute-reevaluate” until I reach my desired goal.
I never did an internship during my graduation or post-graduation, so the first break I had as a scientist was at TIFR, Mumbai. I had joined the Department of Theoretical Astrophysics. It was a requirement for the theoretical physics candidates in the graduate school to do an experimental project. My first scientific project was experimental; it involved testing a large-volume LaBr detector for gamma rays. It was in the Department of Nuclear and Atomic Physics under Prof. Indranil Majumdar. The second project I did was on the inverse comptonization process. My advisor was on Sabbatical to Harvard then, and I figured out the project independently. I wanted to study the role of inverse comptonization in emission from Gamma Ray Bursts and Supernovae. I invested a lot of time in adequately laying out the theory of comptonization (which had a significant literature survey part). Ultimately, I only had a little time to improve the final application part. The project taught me to balance a comprehensive literature survey and the main project. While researching, one must remember that the ratio of the effort for “new” vs the effort for “a comprehensive literature survey” must be greater than unity.
During my PhD, I studied the deaths of massive stars using radio and x-ray emission. I used data from the Extended Very Large Array (EVLA), Giant Meter Wave Radio Telescope (GMRT), and Chandra and XMM-Newton, space-based X-ray telescopes. I used to travel to the GMRT, Khodad (Pune), to conduct the radio observations. The process of radio and X-ray data analysis is very computationally extensive. As I told you before, I was on a steep learning curve in computer literacy. Initially, It was a challenge, but I became very good at it with more practice, failures, and sustained effort. During the data analysis process, I learned a lot about Bash Scripting, Fortran, and Python. When I think of it now, the effort paid off well, as after my PhD, I shifted into the numerical simulations field, where all the computing skills I had acquired proved very useful.
Tell us about your career path after your PhD
During my 1st post-doctoral research work, I learned how to use state-of-the-art supercomputers, debug HPC codes, use MPI programming, optimize, and use visualization tools. In addition, I ventured into studies of turbulence and energy injection by supernovae at Galactic scales. I even made steps toward developing my hydrodynamic simulation codes. During my stay at IISc, I attended the “Le Houches School” on numerical astrophysics; there, I had in-depth lessons on the fundamental algorithms used for solving various kinds of PDE (partial differential equations). The school provided information about state-of-the-art techniques, and I spent much time learning about them. IISc was where I became a computational physicist. Theoretical physics is fun; however, trying to simulate physical phenomena has another dimension – numerical solutions solve an approximation of the actual equation; therefore, one has to be extra careful in discretizing the equations to maintain the fidelity of the numerical approach. In short, coming up with a numerical scheme offers a unique insight into the nature of physical laws – you understand their domain of applicability even better. Furthermore, as the physical systems being studied become more and more complex, simulations offer a unique view of the possible solutions. As Richard Hamming said, “The purpose of (scientific) computing is insight, not numbers.”
After IISc, I got an opportunity to work at the Max Planck Institute of Astrophysics (MPA), Garching, Germany. At MPA, I moved to another problem, simulating the nuclear burning during the final moments of a massive star. I was supposed to use an in-house simulation code, Prometheus, for these simulations. The code was poorly documented, so I had to read through large parts of the code to debug and modify it. I refactored the code’s nuclear reaction network and weak reaction rate module. The code relied heavily on COMMON blocks, which were incompatible with OpenMP, so I had to rewrite a significant part of the nuclear reaction network using Modern FORTRAN. Again, it was a very fruitful experience. Besides, MPA was quite an international place, and I could meet many good astrophysicists worldwide. My advisor at MPA, Prof. Thomas Janka, is very kind and gentle but very fact-oriented regarding scientific discussions. I think it was great to learn the German way of doing Science – stay with the facts and do not overstate your results without a strong reason. Caring about quantitative results is essential in Science, as Science deals with rational reasoning, and one cannot reason without establishing correct facts.
In 2019, COVID stuck, and the institutes were deserted. Luckily, one was allowed to come to the institute if one was not using public transport, and I used to bike to work. Many people felt the effects of isolation caused by the home office. However, I did not mind being alone at the institute (which almost lasted two years). During this time, we had the challenge of systematically analyzing a large set of Core-collapse supernova models, which my colleague Dr. Robert Bollig simulated. Because of the COVID-19 measures, there were no people at the institute, and I could get long periods of silence and an unbroken focus. I started from scratch and developed an entire pipeline to analyze almost half a petabyte of simulation data. I handed over a fat compilation of analysis results to Thomas, who remarked, “Naveen, it seems you have written a second thesis during COVID.” During this time, I wrote codes for visualizing 3D data, and one of my visualizations was published in a German Astrophysics Magazine (Sterne und Weltraum). I even got a token reward for submitting it. The visualization became quite popular, was used on Origin’s grant proposal cover, and was printed onto the institute coffee mug. It was fun to share our work with all the visitors through the coffee mug 🙂 In short, the MPA times were exciting; I honed my computing skills, learned a broad range of techniques, and had an enriching experience in the astrophysics of stars – the cauldrons of the cosmos where all the elements that form life are synthesized. Ultimately, I could contribute to the fundamental question – the Origin of life.
After MPA, I sought an opportunity and was offered a position at the Finnish Meteorological Institute in Helsinki. I had another alternative, which was working on nuclear fusion technology at Marvel Fusion GmbH. Fusion is a fascinating topic; its two primary flavours are magnetic confinement fusion and inertial confinement fusion. I was fascinated with the idea of creating a miniature sun on Earth, and the physics of it seemed so broad and exciting that I opted to join Marvel Fusion. At Marvel Fusion, I am having a lot of fun learning and doing new problems in the physics of high-energy-density plasmas.
How did you get your first break?
I would call TIFR the place where I got my first break as a scientist. I produced my first scientific papers at the institute. For someone like me who would not have been able to afford a GRE to go abroad, it was simply amazing—at TIFR, one had the opportunity to listen to talks from famous scientists and Nobel laureates. The institute has an outreach program called “Chai and Why.” It is organized on Sunday; an institute member gives a talk on a scientific topic to audiences as young as ten. I gave a talk on “The Life of Massive Stars.” I enjoyed interacting with the curious young people and addressing their curiosity. The best thing about the institute was that physics, chemistry, mathematics, and computer science research were conducted under one roof. As a result, one could attend Colloquiums on many diverse topics. In short, TIFR is where I stepped into the field of Science as a professional.
What were some of the challenges you faced? How did you address them?
Several challenges I faced are mentioned above, so I am not listing them here.
Where do you work now?
I am a theoretical physicist at Marvel Fusion GmbH (Bavaria, Germany). The company focuses on the generation of energy using nuclear fusion. Our approach can be broadly classified under “Inertial Confinement Fusion.” (which is quite different from the fusion using Tokamaks and Stellarators). In layperson’s terms, one can describe it as a group of strategies aiming to create a miniature thermonuclear device. For a general understanding, one can look up the ICF experiments being conducted at the NIF (National Ignition Facility) in the United States of America.
What problems do you solve?
As a theoretical physicist, I contribute to the theoretical advancement of our fusion concept, validating it and making it more accurate using numerical simulations. Most problems are related to laser propagation, laser-plasma interactions, nuclear fusion, and related instabilities.
What skills are needed for your role? How did you acquire the skills?
First and foremost, an excellent grasp of physics is a must—more specifically, in addition to bare-knuckle theoretical skills, a strong physics intuition helps a lot. A second essential skill is a strong expertise in numerical methods for simulating physical systems and an aptitude for developing simulation codes for HPC (High-Performance Computing) platforms.
As evidenced by my previous answers, I have been doing physics research for a long time. Over time, I have developed a reasonably good physical intuition and can understand new domains of physical problems easily—it usually has a steep learning curve, and it is a very satisfying experience. Moving from theoretical astrophysics to ICF plasma physics required me to read a lot about plasma physics. I thoroughly enjoyed and continue to do so, as plasma physics is a vast subject with many applications and unsolved problems.
Regarding the computational physics skills needed for the job, you know by now that for me, it started with being computer illiterate at the start of my PhD at TIFR and going all the way to using some of the world’s most powerful supercomputers at the Max Planck Institute in Garching. It involved a long effort, practice, and patience. Computing is evolving rapidly, and to stay at the forefront, you must keep making an effort continuously. By the way, the same goes for any field you pursue.
What’s a typical day like?
A typical day involves looking at the results of simulations and experiments and finding explanations. It typically consists of a lot of programming, as the work is quantitative by nature, and we seek understanding through simulating physical phenomena. Sometimes, we have meetings and discussions to find solutions as no one carries all the knowledge. Still, our team is exceptionally rich in theoretical and numerical skills. Sometimes, one talks to people in engineering groups and learns about their work, which ultimately helps one build a holistic picture of the shared enterprise aiming to achieve commercially viable fusion.
What is it you love about this job?
I love the thrill of exploring high-energy-density plasma physics with a fantastic group of colleagues. Although we work in an industrial setting, which is not the same as an academic setting, we are free, and our workplace promotes independent thinking. One of the best things is that I can now talk to engineers and see how they work closely. Sometimes, I walk into the lab to see the devices and electronics being worked on. I plan to build my little workshop and restart building toy models of aeroplanes and small physics experiments (especially optics) to have fun in my spare time.
How does your work benefit society?
Humans have a natural desire for understanding the world. As an astrophysicist, I could contribute a bit to that knowledge, and it contributes to the desire of humans to understand their beginnings. As a fusion physicist, if we can make commercial fusion possible, it would significantly impact the future of civilization. Clean energy could power the advance of society and steer us away from climate catastrophe. One must remember that at the end of the day, the work we do and the professions we choose help us find meaning in our lives. All one has to ensure is to put one’s heart and soul into the work (even failures and null results are not to be looked down upon; they are part of the game), and it may be helpful to the greater society someday. Just like poets write poems and artists make art to express themselves, scientists do science to answer their questions. Sometimes, their contributions last much longer than their lives, and society benefits.
Tell us an example of a specific memorable work you did that is very close to you!
I cannot pinpoint a specific example; however, I can offer a glimpse into the general excitement one experiences while pursuing a scientific project.
Working on my thesis was a unique experience overall. The ideas behind my first paper were developed by me working alone. To see them coming to explain a real astrophysical object (a supernova’s radio emission) was a very satisfying experience. After finishing my thesis, I moved away from the thesis research topic. I decided that it was time to pursue numerical simulations of astrophysical systems. By the end of my PhD, I was well versed in the techniques of HPC. I thought it was time to delve into numerically solving the equations of physics (fluid dynamics, magneto-hydrodynamics), so I wrote to Prof. Prateek Sharma (who had just moved to India back from Princeton University, U.S.) at IISc if he had an open position. He was very open-minded, and although I had yet to gain direct-proven experience in computational physics, he agreed to hire me as a postdoc. I remember my first day at IISc, where Prateek introduced me to the supercomputer job submission software. After some practice, I soon ran my first set of simulations on a supercomputer, CRAY XC40 (nicknamed SAHASRAT), at IISc. I worked very hard to get the project moving, writing analysis codes and debugging them, and soon the results started appearing. We were able to shed light on a significant problem in astrophysics (the energy injection by supernovae into the galactic medium). I was delighted, and the work is still fresh in my memories. The thrill of doing something new in a new field, using entirely new techniques, and being able to make progress is a great feeling.
Nevertheless, I take all my projects very seriously and commit myself to them, so I get a kick out of finishing them. They have become part of my memory.
Your advice to students based on your experience?
My experience is that “Books are the best friends one can have, and one can find comfort in them through the thick and thin of one’s life.”
Comprehensive advice:
Read a lot, think about the world, and question more. It must be emphasized that plain reading is not enough; one has to digest the material, which requires thought and asking questions. One doesn’t have to master everything in one’s courses; one has to master the parts crucial to building further knowledge. No matter your subject, you must examine the facts critically and question the established norms, theories, and paradigms to understand them better. Don’t be afraid of your limitations, as only by knowing them can you break them. If you are not the top performer in your school or amongst your siblings, don’t worry; each of us will have a distinct path. Be patient with your progress, as knowledge and skill building takes time. Don’t be worried if you are not from a well-to-do family; if you try hard enough, you will find mentors, well-wishers, and resources in the form of scholarships to continue your journey. For example, I paid approximately 3000 INR for three years of college fees, and I don’t feel less compared to someone who went to more privileged places. No one chooses their initial conditions; however, one can set their path. Over time, I worked with people from well-known institutions. I worked at many good institutions, and although adding more money/resources to my journey would have made it more accessible, it would not have made a difference to the outcomes. Besides, it has made me more understanding of the struggles of others.
One must remember that there is no absolute measure of success; it is simply the best you can achieve with the available resources at any given moment. There are no shortcuts to success; it is sheer will, hard work, and commitment. Wolfgang Pauli’s hypothesis of the existence of the neutrino was confirmed by experiment only after 25 years. Having been notified by telegram of its discovery, Pauli wrote to Reines and Cowan, “Thanks for the message. Everything comes to him who knows how to wait.” In this sentence, “how to wait” doesn’t mean idling away; it means staying committed and patient in pursuit of the goal.
When I compare the resources available to children in the Western world, I can only say that Indian students are commendable and comparable to the best in the world, and they hold great promise. These words from Kalpana Chawla (she died in the Space Shuttle Columbia disaster) encouraged me a lot during my undergraduate days: “The path from dreams to success does exist. May you have the vision to find it, the courage to get on to it, and the perseverance to follow it“. Kalpana was from Karnal and was born to a family who moved to India after the partition. She challenged the norms of those decades to become the first Indian-born female astronaut. Her father told us about her journey on our college finishing day – she led an exemplary life and is a motivation to many worldwide.
Young readers should listen to the thoughts of people they think have made a difference. Sometimes, you can draw inspiration from their thoughts when going is hard and things seem stuck.
Regarding learning, formal education (school, College, and PhDs) aims to prepare you to be an independent thinker. The goal is to teach you to organize your thoughts, chart out a plan, and stay committed to it. In the socio-economic setup we grew up in India, there are specific well-established paths to prosperity. However, think of all the explorers, thinkers, and seafarers who sought the unknown and changed the course of human civilization. Failing is not fatal (most of the time), and as Prof. Antia would say, it only means that you need to try harder or you are not trying it correctly. Last but not least, at the end of the day, you have to be able to stand up to your cause, stand up to the pressure, and follow your heart. Where there is a will, there is a way.
Future Plans?
It usually takes much work to state one’s future journey accurately. Besides, there is fun in having a bit of unpredictability. However, for now, I plan to continue working on fusion technology and want to invest time in developing open-source codes. I want to read and learn more about biophysics, artificial intelligence, geophysics, and quantum computers (sounds like a long list, and I want to dive into them). I would also like to be a teacher in another decade or two to share my knowledge and skills with underprivileged kids. If I have saved enough money by the time I retire, I would like to sponsor higher education for children from less privileged backgrounds. Ultimately, I would leave my savings to a trust that provides opportunities to kids from challenging economic backgrounds.