Tag: science

Conversation with Aparna Deshpande

Welcome to the podcast, Pratidhavani – Humanizing Science

Aparna Deshpande is an Associate Professor of Physics at IISER Pune, specializing in atomic-scale exploration of two-dimensional materials and their interfaces using scanning tunneling microscopy. She is deeply engaged in research on nanomaterials and is active in physics education (as part of the department of science education at IISER Pune), communication, and outreach at IISER Pune.

Aparna is also the faculty in charge of the Smt. Indrani Balan Science Activity Centre at IISER Pune, where she leads diverse science outreach and STEM education initiatives, promoting hands-on multi-lingual learning and innovative workshops for students and teachers across India.

In this conversation, we explore her research in physics and science education.

You can also watch or listen on spotify

References:

[1] “Dr. Aparna Deshpande.” Accessed: Sept. 25, 2025. [Online]. Available: https://draparnadeshpande.github.io/portfolio/

[2] “Dr. Aparna Deshpande (@DrAparnaIISERP) / X.” X (formerly Twitter). Accessed: Sept. 25, 2025. [Online]. Available: https://x.com/draparnaiiserp

[3] “Aparna Deshpande | LinkedIn.” Accessed: Sept. 25, 2025. [Online]. Available: https://www.linkedin.com/in/aparna-deshpande-01927015/?originalSubdomain=in

[4] “Aparna Ramchandra Deshpande – Google Scholar.” Accessed: Sept. 25, 2025. [Online]. Available: https://scholar.google.com/citations?user=f5FnqMIAAAAJ&hl=en

[5] “Aparna Deshpande – IISER Pune.” Accessed: Sept. 25, 2025. [Online]. Available: https://www.iiserpune.ac.in/research/department/physics/people/faculty/regular-faculty/aparna-deshpande/259

[6] J. Poskett, Horizons. London, UK: Penguin Books, 2023. Accessed: Sept. 25, 2025. [Online]. Available: https://www.penguin.co.uk/books/313423/horizons-by-poskett-james/9780241986264

[7] P. Lockhart and K. Devlin, A Mathematician’s Lament. Illustrated ed. New York, NY: Bellevue Literary Press, 2009. https://www.blpress.org/books/a-mathematicians-lament/

Satish Dhawan – truly a man for all seasons

Image credit: Current Science 119, no. 9 (2020): 1427–32

Today is the birth anniversary of Satish Dhawan (25 September 1920 – 3 January 2002). He was probably India’s best scientist-administrator who headed institutions such as the Indian Institute of Science and the Indian Space Research Organization. With a PhD from Caltech, he came back to India and set up a marvellous research enterprise on fluid mechanics, including aerospace science and engineering. He mentored some of the outstanding scientists of India and led scientific institutions with vision, openness and informality, which is still a great benchmark to emulate1.

Below are a couple of historical documents related to Dhawan:

The first one is a lecture note from 1979, on making a case for a national satellite system and how it influences science and scientific activity (a copy of this note has been reproduced in a wonderful tribute to Satish Dhawan written by P. Balaram on his birth centenary2).

The next one is a beautiful perspective article written by Dhawan on ‘Bird Flight’ from an aerodynamics perspective3. It is a detailed overview of the dynamics of bird flight and shows Dhawan’s interest and ability to bridge two facets of science. It is a prototypical example of interdisciplinary research.

Finally, let me end the blog with a quote from P. Balaram on Satish Dhawan4:

“Dhawan mentored some remarkable students and built the discipline of aeronautical engineering at the Institute. He influenced aeronautical research and industry in India in a major way. He shepherded the Indian space programme following Vikram Sarabhai’s untimely death. He served the Indian scientific community in many ways. His stewardship transformed IISc. How then do we describe such a man? Dhawan studied English literature obtaining a Master’s degree in his youth. It may therefore be appropriate for me to borrow a 16th century description of Sir Thomas More:


‘[Sir Thomas] More is a man of an angel’s wit and
singular learning. I know not his fellow. For where is
the man of that gentleness, lowliness and affability?
And, as time requireth, a man of marvelous mirth and
pastimes, and sometime of as sad gravity. A man for
all seasons.’

Satish Dhawan was truly a man for all seasons.”

Happy Birthday to Prof. Satish Dhawan!

References:

  1. Current Science, in 2020, had a section of a volume dedicated to the birth centenary of Satish Dhawan, and has a foreword by his daughter and articles by many of his students and co-workers. https://www.jstor.org/stable/e27139029 ↩︎
  2. P. Balaram, “Satish Dhawan: The Transformation of the Indian Institute of Science, Bangalore,” Current Science 119, no. 9 (2020): 1427–32. This reference has many interesting references, including a handwritten obituary of CV Raman written by Dhawan https://www.jstor.org/stable/27139041. ↩︎
  3. S. Dhawan, “Bird Flight,” Sadhana 16, no. 4 (1991): 275–352, https://doi.org/10.1007/BF02745345. ↩︎
  4. P. Balaram, Current Science 119, no. 9 (2020), page 1432. https://www.jstor.org/stable/27139041. ↩︎

Sir MV on Education

In India, “National Engineers’ Day is celebrated every year on September 15 to honor the birth anniversary of Sir Mokshagundam Visvesvaraya, one of India’s greatest engineers”. Sir MV, as he was known, is one of the 20th-century Indians I admire. He was a forward-looking statesman who contributed immensely to building India (literally and figuratively). MV was a well-read and well-travelled person for his era, and wrote a few books and memos that are still pertinent to the current developments in India and the world.

Reconstructing India (1920)

One of his books, Reconstructing India (1920), reveals his thoughts on how and why India needs to reconstruct itself based on knowledge in science, technology and humanities. The title page is shown below, and the book is free to read online, thanks to the Internet Archive.

The book, as mentioned by MV in the preface, was written just after the First World War, and contemplates problems faced by India in light of geopolitical developments. In the 17 chapters of the book, divided into 4 parts, MV discusses specific issues faced by India, and proposes that political and administrative reforms can help India become a progressive society.

The largest part of the book is on economic reconstruction, in which he proposes contemporary methods (for the 1920s) to improve various sectors of manufacturing, including agricultural technology and communication media.

The third part of the book is on social reforms, and in there, he has a dedicated chapter on Education, which caught my attention, and I found it relevant even for today’s India.

Education, Humanities, and STEM

It is important that students of science and technology have a good exposure to some aspects of the humanities, including economics, history and philosophy. The pursuit and ability to choose good problems in science and technology critically depend on the social and economic structure in which they are practiced in universities and research institutions. MV anticipated this and highlights it as:

“Secondary and university education, though producing many able recruits for subordinate positions in the Civil Service, does not provide the men needed to carry on the work of agriculture, engineering, commerce and technology. The provision for training in economics and history is inadequate, and the study of those subjects is even discouraged. An attempt is actually made to teach economics in such a way as to render India’s emergence from a state of dependency difficult.”

Even in 2025, I would suggest that STEM students pay attention to economics, as it anchors them to understand the need and functions of a society, and therefore, their work can be calibrated accordingly. This is not to discourage open-ended research, but to understand how natural sciences are connected to the societal thoughts and needs. It gives us a broader understanding of the context, which is so important while understanding the evolution of ideas.

Comparative Education Systems

There is always a lot to learn from various societies and cultures. In order to do so, one needs comparative analysis. This helps one to choose some good elements from a society that can be emulated elsewhere. MV compares and comments on the 1900s British educational system in contrast to the German and Japanese counterparts. Note that India in the 1920s was still a British colony, and in a way, MV is critical of the system in which he himself was educated and trained. As he notes:

“Britain herself has had to pay a heavy price for her hand-to-mouth policy in regard to education. The educational chaos still existing there compares unfavourably with the great yet orderly progress made by Germany and Japan, both of which countries, after weighing and testing the educational systems of the world, absorbed the best of all.”

These were words written long before the Second World War, and give us a glimpse of how German and Japanese systems were functioning in the 1920s and had a lot to offer to the world. Of course, history took its own path, and German and Japanese society had other ideas.

Incidentally, I am writing this piece sitting in Leipzig (eastern Germany), and I am amazed by its architectural marvels that date back centuries. Indeed, German society had (and has) a lot to offer to the world. As MV indicates above, we need to absorb the best that is on offer. In doing so, we also need to reject that which is not good for any society.

Liberal Education and Financial Support

He further adds how liberal education adds value to a society, and calls not only the government but also the people to recognize the importance of financial support for education.

“Both the Government and the people must recognize that only by pursuing a liberal educational policy, and making generous financial provision for schools and colleges can they lift India out of her present low condition and ensure rapid progress.”

These words still hold good, and as a society, India has to re-emphasize modern education that helps us become not only better doctors and engineers, but also better human characters that can add value to the “modern” world.

Call to Action

In the final part of the book, MV makes a passionate appeal to the people of India, calling them to take action and move towards becoming a progressive nation:

“Do the people of India propose to profit by the lessons which world experience has to teach them, or will they be content to allow matters to drift and themselves grow weaker and poorer year by year?
This is the problem of the hour. They have to choose whether they will be educated or remain ignorant; whether they will come into closer touch with the outer world and become responsive to its influences, or remain secluded and indifferent; whether they will be organized or disunited, bold or timid, enterprising or passive ; an industrial or an agricultural nation ; rich or poor ; strong and respected, or weak and dominated by forward nations. The future is in their own hands.”

Indeed, the future is in our hands, and these words written more than 100 years ago still resonate loudly. We need more engineers like Sir MV. The reason he was so effective was that he combined thinking and doing. Importantly, the lesson we can learn from MV’s life and by reading this book, is that an open mind can grasp good ideas at any time and anywhere. Implementing those ideas is an equally important challenge, and MV was up to this in his own way. Are we, as Indians, open to this prospect and engineer our future?

Gardner’s Synthesis

Once in a while, during my research, I come across writing by scholars from other disciplines that gives me a perspective that not only helps me to grasp the complexity of learning across disciplines, but also resonates with some thoughts on education.

Howard Gardner is one such academic who works on developmental psychology and has researched extensively on cognition and education. He has written ~30 books and ~1000 articles, and blogs regularly, even at the age of 82 or so. His recent book is titled A Synthesizing Mind.

Howard Gardner is a renowned Harvard academic and, as his book describes him as follows:

“Throughout his career, Gardner has focused on human minds in general, or on the minds of particular creators and leaders. Reflecting now on his own mind, he concludes that his is a ‘synthesizing mind’—with the ability to survey experiences and data across a wide range of disciplines and perspectives. The thinkers he most admires—including historian Richard Hofstadter, biologist Charles Darwin, and literary critic Edmund Wilson—are exemplary synthesizers. Gardner contends that the synthesizing mind is particularly valuable at this time and proposes ways to cultivate a possibly unique human capacity.”

While exploring the book and the related material, I came across an interview with Howard Gardner. In there, he is conversing about the theme of the book and discusses the synthesis of thought across disciplines. One of the pertinent aspects of learning is to know how innovation can be fostered by cross-disciplinary exploration without diluting disciplinary rigour. As Gardner says:

“I am not opposed to disciplinary learning—indeed I am an enthusiastic advocate. Any person would be a fool to try to create physics or psychology or political science from the start. But if we want to have scholars or professionals who are innovative, creative—and innovation is not something that we can afford to marginalize—then they cannot and should not be slaves of any single discipline or methodology.”

As a physicist, I can relate to this thinking within my discipline, and how innovative ideas, over the ages, have emerged by bringing ideas from mathematics, engineering and biology into physics. Particularly, the combination of biology, physics and mathematics is one of the most exciting frontiers of human exploration today, and Gardner’s words apply well in this scenario.

Going beyond science, I am always intrigued and amazed by artists (especially musicians) who can create art that simultaneously draws the attention of specialists and generalists. This is not a trivial achievement, and as a scientist, I am always trying to understand how artists resonate so well with the public. Gardner, in the abovementioned interview, frames this problem by looking at the goals of science and arts, and draws a contrast that is worth noting:

“Most scholars and observers like to emphasize the similarities between the arts and the sciences, and that is fine. But the goals of the two enterprises are different. Science seeks an accurate and well supported description of the world. The arts seek to capture and convey various aspects of experience; and they have no obligation other than to capture the interest and attention of those who participate in them.

Of course, there are some individuals who excel in both science and art (Leonardo is everyone’s favorite example). But most artists—great or not—would not know their way around a scientific laboratory. And most scientists—even if they like to play the violin or to draw caricatures or to dance the tango—would not make works of art or performances that would interest others.”

I partially agree with this assessment, as I know a few scientists who are deeply involved in various forms of art (including music) and do it very well, even at the professional level. In a way, Gardner is re-emphasizing the “two cultures” debate of C.P. Snow. My own thoughts on this viewpoint are ambivalent, as I see science, arts and sports as important pursuits that cater to different facets of the human mind. Of course, when it comes to expertise, the division may matter. There is a lot more to learn about the interface of art and science, at least for me.

Anyway, Gardner is a fabulous writer, and his blogs and books are worth reading (and studying) if one is seriously interested in understanding how to synthesize thought across disciplines.

Since we are discussing synthesis of thought, which is a kind of harmony, and coming together, let me end the blog with a line from Mankuthimmana Kagga by the Kannada poet-philosopher D.V. Gundappa:

“ಎಲ್ಲರೊಳಗೊಂದಾಗು ಮಂಕುತಿಮ್ಮ” (Eladaralongodhagu manku thimma)

which loosely translates to: oh fool…be one among all (blend into world, living in harmony).

Harmony of disciplines and minds – how badly the world needs it today?

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.

Some Optical and IR observatories in India

Below are ‘locations of some of the optical and infrared observatories marked on the Indian map’.

from: Narendranath, Shyama, Shashikiran Ganesh, Dipen Sahu, et al. 2025. “Solar System Research Prospects for the Decade and Beyond.” Journal of Astrophysics and Astronomy 46 (2): 34. https://doi.org/10.1007/s12036-025-10060-0.

Happy Independence Day & de Broglie’s birthday

Happy Independence Day to my fellow Indians !

15th Aug also happens to be birthday of Louis de Broglie, the famous French physicist who played a critical role in understanding wave-particle duality in quantum physics, and laid an important foundation through his formula

λ = h / p ;

where, λ is the wavelength of quantum particle with momentum p and h is the Planck constant.

See here for more details.

de Broglie studied and discovered the wave nature of electron, for which he received the Nobel prize in physics in the year 1929. In 1920s, understanding light from a quantum mechanical viewpoint was a challenge. Reconciling light, both as a particle and a wave, was counterintuitive and required a leap of thought that was provided by de Broglie. On 12th Dec 1928, delivered his Nobel lecture and mentions:

“I thus arrived at the following overall concept which guided my studies:
for both matter and radiations, light in particular, it is necessary to introduce
the corpuscle concept and the wave concept at the same time. In other words
the existence of corpuscles accompanied by waves has to be assumed in all
cases. However, since corpuscles and waves cannot be independent because,
according to Bohr’s expression, they constitute two complementary forces
of reality, it must be possible to establish a certain parallelism between the
motion of a corpuscle and the propagation of the associated wave.“

This duality still remains, as we try understand the nature of light and harness it for information processing.

Interestingly, de Broglie was one of persons who nominated CV Raman for the Nobel prize in 1930 ! Below snapshot is from the Nobel prize nomination archives.

Conversation with Kollegala Sharma

Welcome to the podcast Pratidhavani – Humanizing Science

Kollegala Sharma is a renowned science communicator and prolific Kannada writer, celebrated for making science accessible through articles, books, radio dramas, podcasts, and translations. A former chief scientist at CSIR-CFTRI Mysore, he has received prestigious awards for his exceptional contributions, including pioneering India’s first Kannada science podcast and editing the state’s popular science magazine, Kutuhali.

In this conversation (in English), we discuss what motivates him to do what he does so well…communicate science…

Spotify link

References:

Akka TV, dir. 2022. Lecture 107 | Science Journalism : Introduction | Shri. Kollegala Sharma. 44:38. https://www.youtube.com/watch?v=031_4I0W9I8.

“Amazon.In.” n.d. Accessed August 6, 2025. https://www.amazon.in/Books-Kollegala-Sharma%60/s?rh=n%3A976389031%2Cp_27%3AKollegala%2BSharma%2560.

“CFTRI.” n.d. Accessed August 8, 2025. https://cftri.res.in/faculty_detail/2062.

Falling Walls Foundation, dir. 2020. Breaking the Wall to Language, Geography and Social Separation. 05:12. https://www.youtube.com/watch?v=_nscnJFd–8.

Kollegala Sharma | Mysuru Literature Festival. n.d. Accessed August 6, 2025. https://www.mysuruliteraturefestival.com/lit-fest-2024/kollegala-sharma/.

Mandram, dir. 2018. Science and Language – Dr Kollegala Sharma. 27:49. https://www.youtube.com/watch?v=dSqO-AOu9io.

Spotify. n.d. “Learn and Unlearn.” Accessed August 6, 2025. https://open.spotify.com/show/1JYHPAvzx3RuWcO8hL6Cjy.

X (Formerly Twitter). 2025. “(4) Kollegala Sharma (@kollegala) / X.” July 27. https://x.com/kollegala.

YouTube. n.d. “Kollegala Sharma.” Accessed August 6, 2025. https://www.youtube.com/channel/UCCtB6my4ohaYOnQvBRnPEuA.

Light as EM wave – in Maxwell’s words

Every year, I teach an optics course to physics majors (including physics iPhD students and MS Quantum Tech students). In the process of introduction, I discuss how light was discovered to be an electromagnetic wave. One of the thrills of this topic is to quote Maxwell from his legendary 1865 paper1, in which he makes this monumental connection. Every time I teach this, I get an intellectual kick, even after doing this for almost 1.5 decades.

The highlighted text is the famous statement. Before that, Maxwell compares his result with two experimental results and confirms his prediction. I follow this up with Hertz’s experiment.

Note: Electric waves and telegraphy were already known before Maxwell’s paper. There were papers that discussed about velocity of light and its connection to electric waves. See this paper2, for example. However, these interpretations were not as comprehensive as Maxwell’s case, and importantly, the field theory viewpoint needed Faraday’s experiments and Maxwell’s interpretation.

  1. Maxwell, James Clerk. 1865. “VIII. A Dynamical Theory of the Electromagnetic Field.” Philosophical Transactions of the Royal Society of London 155 (January): 459–512. https://doi.org/10.1098/rstl.1865.0008.
    ↩︎
  2. https://www.ifi.unicamp.br/~assis/Weber-Kohlrausch(2003).pdf ↩︎

THE DIARY AND OBSERVATIONS OF THOMAS ALVA EDISON

Thomas Alva Edison was one of the greatest inventors we know about. Sometime ago, I stumbled upon a book titled THE DIARY AND OBSERVATIONS OF THOMAS ALVA EDISON, and it was an interesting read. In there, we obtain an insight into Edison’s view on many different subjects, including education, work, religion, etc. Edison was a person with strong views. His working methods were unconventional. Here are a few interesting facts I learnt from this book:

1) Edison had to recruit many executives to his labs; he always emphasized on a memory test and gave them a questionnaire to answer. He insisted that memory is very important for decision making, and he usually employed those people who had very good memory. Edison wrote “…Certainly the brain should have the facts. If a brain possesses an enormous number of facts, those facts, through action of the subconscious mind, will automatically keep themselves available when needed and will automatically keep themselves out of the way, not interfering when not required.”

2) Edison’s view on education was interesting and bold for his times, and he believed that learning through movies would be vital for future education. As early as the 1890s, he said that the best way to teach geography is either by taking the student on a tour or by showing them a movie. Edison wrote

“…motion pictures can be applied to a scientific, systematic course of memory training in the schools, taking the children at an early age when the mind is plastic enough to adapt itself most readily to new habit of thought.

Most of our text books fail on two big counts. They are not sufficiently human, and their application is not sufficiently practical”

3) In the following lines, Edison gives an insight into how he worked: “When I want to discover something, I begin by reading up everything that has been done along that line in the past-that’s what all these books in the library are for. I see what has been accomplished at great labor and expense in the past. I gather the data of many thousands of experiments as a starting point, and then I make thousands more.”

“ …..The motive that I have for inventing is, I guess, like the motive of the billiard player, who always wants to do a little better-to add to his record. Under present conditions I use the reasonable profit which I derive from one invention to make experiments looking towards another invention…..”

4) Edison rates the phonograph as his greatest discovery. He writes, “Which do I consider my greatest invention ? Well, my reply to that would be that I like the phonograph best. Doubtless this is because I love music. And then it has brought so much joy into millions of homes all over this country, and , indeed, all over the world.”

5) The following quotation by Joshua Reynolds was hung in every room of Edison’s laboratory “ There is no expedient to which a man will not resort to avoid the real labor of thinking”

There are many more fascinating thoughts of Edison, many agreeable and a few disagreeable ones, in the above-mentioned book, and if you happen to find it, read it through…it’s a classic and insightful read.

The above text is from a 2011 post on my old blog.