Tag: research

When Chandra wrote to Hawking

Learning is a lifelong process, and even the best researchers have to update their knowledge as and when they come across new information. Subrahmanyan Chandrasekhar was undoubtedly one of the most accomplished mathematical astrophysicists in the 20th century, and his range of topics covered almost all aspects of astrophysics.  Chandra (as he was known) was a lifelong learner, and took up new topics within astrophysics, researched them deeply, and wrote definitive books on them, which are still of great utility even today. In his research process, Chandra consulted various scholars across the world, irrespective of their age, and learned new things.

In 1967, Chandra, aged 57, wrote a letter to a 25-year-old researcher, Stephan Hawking, to learn more about his work ‘on the occurrence of singularities in cosmology’. In this letter, which is written in a desperate tone, Chandra mentions that he is grappling with some mathematical aspects of Stephen Hawking’s work and is asking him for references that he can consult to understand his papers. Chandra describes reading Hawking’s papers as  ‘climbing a staircase moving downwards’. Below, I reproduce the letter (from the University of Chicago archives).

 To this letter, Hawking dutifully replies (see below), suggesting specific books on topology and differential geometry. Hawking also suggests some of his published papers. Hawking himself downplays his knowledge of mathematical aspects related to the work, and mentions that it improved after he consulted the mentioned books. Below, I reproduce the handwritten letter (from the University of Chicago archives).

There are two aspects that are interesting to note:  one is the fact that even accomplished researchers have to learn and relearn many things as they get exposed to new information, which calls for humility and setting aside egos, and the second aspect is that ideas are built on existing ideas available at that time, and a major part of it is to learn from papers, books and of course communicating with people, as Chandra did in this case.

Science, after all, is a human endeavor.

A bit of advice…to students

To paraphrase something I tell my students, especially when they are starting a research project –

There are certainly many people in the world who think better than us. But the competition reduces when it comes to the people who take their thoughts and ‘do’ something with them. Novelty of ideas is in the novelty of connections of ideas. There is always more scope for new connections of old ideas.

Generally, the game is won not in out-thinking, but in out-doing. This does not mean that doing excludes thinking. In fact, many times, doing fosters thinking.

15 years at IISER Pune – Journey so far

Today, I complete 15 years as a faculty member at IISER-Pune. I have attempted to put together a list of some lessons (based on my previous writings) that I have learnt so far. A disclaimer to note is that this list is by no means a comprehensive one, but a text of self-reflection from my viewpoint on Indian academia. Of course, I write this in my personal capacity. So here it is..

  1. People First, Infrastructure Next
    As an experimental physicist, people and infrastructure in the workplace are of paramount importance. When I am forced to prioritize between them, I have chosen people over infrastructure. I am extremely fortunate to have worked with, and continue to work with, excellent students, faculty colleagues, and administrative staff members. A good workplace is mainly defined by the people who occupy it. I do not neglect the role of infrastructure in academia, especially in a country like India, but people have a greater impact on academic life.
  2. Create Internal Standards
    In academia, there will always be evaluations and judgments on research, teaching, and beyond. Every academic ecosystem has its own standards, but they are generalized and not tailored to individuals. It was important for me to define what good work meant for myself. As long as internal standards are high and consistently met, external evaluation becomes secondary. This mindset frees the mind and allows for growth, without unnecessary comparisons.
  3. Compare with Yourself, Not Others
    The biggest stress in academic life often arises from comparison with peers. I’ve found peace and motivation in comparing my past with my present. Set internal benchmarks. Be skeptical of external metrics. Strive for a positive difference over time.
  4. Constancy and Moderation
    Intellectual work thrives not on intensity alone, but on constancy. Most research outcomes evolve over months and years. Constant effort with moderation keeps motivation high and the work enjoyable. Binge-working is tempting, but rarely effective for sustained intellectual output.
  5. Long-Term Work
    We often overestimate what we can do in a day or a week, and underestimate what we can do in a year. Sustained thought and work over time can build intellectual and technical monuments. Constancy is underrated.
  6. Self-Mentoring
    Much of the academic advice available is tailored for Western systems. Some of it is transferable to Indian contexts, but much of it is not. In such situations, I find it useful to mentor myself by learning from the lives and work of people who have done extraordinary science in India. I have been deeply inspired by many people, including M. Visvesvaraya, Ashoke Sen, R. Srinivasan, and Gagandeep Kang.
  7. Write Regularly—Writing Is Thinking
    Writing is a tool to think. Not just formal academic writing, but any articulation of thought, journals, blogs, drafts, clarifies and sharpens the mind. Many of my ideas have taken shape only after I started writing about them. Writing is part of the research process, not just a means of communicating its outcomes.
  8. Publication is an outcome, not a goal Publication is just one outcome of doing research. The act of doing the work itself is very important. It’s where the real intellectual engagement happens. Focus on the process, not just the destination.
  9. Importance of History and Philosophy of Physics
    Ever since my undergraduate days, I have been interested in the history and philosophy of science, especially physics. Although I never took a formal course, over time I have developed a deep appreciation for how historical and philosophical perspectives shape scientific understanding. They have helped me answer the fundamental question, “Why do I do what I do?” Reflecting on the evolution of ideas in physics—how they emerged, changed, and endured—has profoundly influenced both my teaching and research.
  10. Value of Curiosity-Driven Side Projects
    Some of the most fulfilling work I’ve done has emerged from side projects, not directly tied to funding deadlines or publication pressure, but driven by sheer curiosity. These projects, often small and exploratory, have helped me learn new tools, ask new questions, and sometimes even open up new directions in research. Curiosity, when protected from utilitarian pressures, can be deeply transformative.
  11. Professor as a Post-doc
    A strategy I found useful is to treat myself as a post-doc in my own lab. In India, retaining long-term post-docs is difficult. Hence, many hands-on skills and subtle knowledge are hard to transfer. During the lockdown, I was the only person in the lab for six months, doing experiments, rebuilding setups, and regaining technical depth. That experience was invaluable.
  12. Teaching as a Social Responsibility
    Scientific social responsibility is a buzzword, but for me, it finds its most meaningful expression in teaching. The impact of good teaching is often immeasurable and long-term. Watching students grow is among the most rewarding experiences in academia. Local, visible change matters.
  13. Teaching Informally Matters
    Teaching need not always be formal. Informal teaching, through conversations, mentoring, and public outreach, can be more effective and memorable. It is free of rigid expectations and evaluations. If possible, teach. And teach with joy. As Feynman showed us, it is a great way to learn.
  14. Foster Open Criticism
    In my group, anyone is free to critique my ideas, with reason. This open culture has been liberating and has helped me learn. It builds mutual respect and a more democratic intellectual space.
  15. Share Your Knowledge
    If possible, teach. Sharing knowledge is a fundamental part of academic life and enriches both the teacher and the learner. The joy of passing on what you know is priceless.
  16. Social Media: Effective If Used Properly
    Social media, if used responsibly, is a powerful tool, especially in India. It can bridge linguistic and geographical divides, connect scientists across the world, and communicate science to diverse audiences. For Indian scientists, it is a vital instrument of outreach and dialogue. My motivation to start the podcast was in this dialogue and self-reflection.
  17. Emphasis on Mental and Physical Health
    In my group, our foundational principle is clear: good health first, good work next. Mental and physical well-being are not optional; they are necessary conditions for a sustainable, meaningful academic life. There is no glory in research achieved at the cost of one’s health.
  18. Science, Sports, and Arts: A Trinity
    I enjoy outdoor sports like running, swimming, and cricket. Equally, I love music, poetry, and art from all cultures. This trinity of pursuits—science, sports, and the arts—makes us better human beings and enriches our intellectual and emotional lives. They complement and nourish each other.
  19. Build Compassion into Science
    None of this matters if the journey doesn’t make you a better human being. Be kind to students, collaborators, peers, and especially yourself. Scientific research, when done well, elevates both the individual and the collective. It has motivated me to humanize science.
  20. Academia Can Feed the Stomach, Brain, and Heart
    Academia, in its best form, can feed your stomach, brain and heart. Nurturing and enabling all three is the overarching goal of academics. And perhaps the goal of humanity.

My academic journey so far has given me plenty of reasons to love physics, India and humanity. Hopefully, it has made me a better human being.

Willow in comparison – Google quantum chip

In scientific research, comparative analysis is an excellent way to objectively quantify two measurable entities. The recent Google quantum chip (named Willow) does that efficiently as it compares its capability with today’s fastest supercomputers. The comparison note on Google’s blog is worth reading.

In scientific analysis, such comparison teaches us three things:

a) how a scientific boundary is claimed to be pushed?

b) how a benchmark problem is used to achieve comparison?

c) what is the current state-of-the-art in that research area?

Some further observations on the work:

  • The theme of the Nature paper reporting this breakthrough is mainly on error correction. Technically, it shows how error tolerance is measured for a quantum device. This device is based on superconducting circuits, which were tested first on a 72-qubit processor and then on a 105-qubit processor.
  • Interestingly, as the authors mention in the paper, the origins of the errors are not understood well.
  • The paper is quite technical to read, and, to my limited understanding as an outsider, it makes a good case for the claim. The introduction and the outlook of the paper are written well, and give more technical information that can be appreciated by a general scientific audience.
  • There is more to come ! It looks like Google has further plans to expand on this work, and it will be interesting to see in which direction they will take the capability. The Google blog shows a roadmap and mentions their ambition as follows: “The next challenge for the field is to demonstrate a first “useful, beyond-classical” computation on today’s quantum chips that is relevant to a real-world application. We’re optimistic that the Willow generation of chips can help us achieve this goal.”
  • In the past 12 months or so, there has been a lot of buzz related to AI tools (thanks to GPTs, Nobels and perplexities :-), which are mainly in the realm of software theoretical development. This breakthrough in the realm of ‘hardware’ tells us how the physical world is still important!

More to learn and explore…interesting times ahead..

Open access : a few thoughts and books

I think that knowledge, especially academic knowledge, should be openly accessible to fellow researchers and the public. Given that most of the academic research in India is public-funded, it is imperative that our work is made available for anyone interested in reading and utilizing the knowledge. This makes a strong case for making our work open to access. Unfortunately, the open-access publication venture has been hijacked by some commercial publishers, who have misused the enthusiasm of academic researchers by converting it into a money-making opportunity via so-called ‘gold’ open-access models, where authors pay exorbitant article processing charges (APCs) to publish their work in the journals.

I have been searching literature to understand the philosophy and economics of open-access publishing models, and recently, by chance, I came across a couple of books by Peter Suber.

First is an open-access book on Open Access. Peter Suber has been a philosopher & open-access advocate for a long time. In this book, he explains what it really means to have open access to knowledge & the related philosophy, including its economics. Link to the book.

Second is a collection of writings on open-access publication (link), and as the online blurb says :

Influential writings make the case for open access to research, explore its implications, and document the early struggles and successes of the open access movement.

The green open-access model is very interesting and pertinent to countries such as India, and as per wiki it is defined as :

Green OA, is the practice of placing a version of an author’s manuscript into a repository, making it freely accessible for the scientific community.

The primary motivation of Open Access was
to provide Open Access to Knowledge to the READER of Publications and; to allow Open Access to AUTHORS Publication (unbiased publication of Knowledge)

Open access in the true sense, should neither have barriers to knowledge consumption nor to knowledge generation and dissemination. Therefore, APCs are a major hurdle to researchers and authors who do not have monetary support. This is most of the global south, and hence, a fair policy is needed to make it more democratic.