Tag: science

Conversation with Binay Panda

Binay Panda is a Professor at JNU’s School of Biotechnology. The Oxford-educated scientist specializes in genome science, cancer genomics, and data integration, while advocating for open science and Indian biofoundries. He is also an avid long-distance cyclist.

In this freewheeling conversation, we discuss his intellectual journey and his thoughts on doing science, particularly in India.

References:

‘B. R. Panda | Official Website of Jawaharlal Nehru University, New Delhi, India’. Accessed 16 April 2026. https://www.jnu.ac.in/content/binaypanda.

Mysite. ‘Home’. Accessed 16 April 2026. https://www.binaypandalab.org.

Mysite. ‘Open Science’. Accessed 16 April 2026. https://www.binaypandalab.org/open-science.

Mysite. ‘People’. Accessed 16 April 2026. https://www.binaypandalab.org/people.

YouTube. ‘Science Frontiers’. Accessed 16 April 2026. https://www.youtube.com/channel/UCaNkEDS8jRgNZciARfza_ag.

Sean B. Carroll. ‘The Story’. Accessed 16 April 2026. https://www.seanbcarroll.com/brave-genius-story.

Dr. Sanjib Malik. Ek Doctor Ki Maut (1990) by Tapan Sinha [ Full Movie in 4K or Ultra HD  ]. 2024. https://www.youtube.com/watch?v=5qLFGW8SU38.

Born & Wolf to Mandel & Wolf

There is an important connection between quantum optics and radio astronomy. Hanbury Brown and Twiss in the 1950s devised the intensity interferometer.

Particularly, they were interested in measuring the ‘diameter of discrete radio sources’. The title of their seminal paper reads “A new type of interferometer for use in radio astronomy”. As the authors claimed in their paper: “The principle of the instrument is based upon the correlation between the rectified outputs of two independent receivers at each end of a baseline, and it is shown that the cross-correlation coefficient between these outputs is proportional to the square of the amplitude of the Fourier transform of the intensity distribution across the source.”(Brown and Twiss, 1954)

First, they tested their technique in a laboratory situation and followed it up with a measurement of the diameter of Sirius. Their technique was a game-changer in measuring the diameter of bright stars.

As the intensity interferometers were being developed, the laser was realized in the early 1960s. Unlike conventional light sources, laser light is coherent, and this brings in unique features that can be used to understand the nature of light. In the context of laser optics, intensity interferometers had immediate utility in studying coherence through correlation measurement. It was logical to combine lasers with intensity interferometers and study the correlation. This combination is what led to the discovery of some fascinating aspects of quantum properties of light, including anti-bunching.

If the book by Born and Wolf is considered a classic on the electromagnetic theory of light, the quantum extrapolation is the book by Leonard Mandel and Emil Wolf titled Optical Coherence and Quantum Optics.

This book discusses the interface of statistical optics, optical coherence, and quantum optics. The core argument of the book starts with probability theory and its connection to fluctuations of light and builds optical coherence, polarization, and eventually quantum optical effects of light. It is a well-written treatise on light with a flavor of experiments (Mandel did some pioneering experiments in quantum optics) and theoretical explanation (a hallmark of Wolf).

In the preface of the book, they bring together the importance of intensity interferometers and the discovery of lasers and explain how and why it led to a deeper understanding of quantum optics:

“Prior to the development of the first lasers in the 1960s, optical coherence was not a subject with which many scientists had much acquaintance, even though early contributions to the field were made by several distinguished physicists, including Max von Laue, Erwin Schrodinger and Frits Zernike. However, the situation changed once it was realized that the remarkable properties of laser light depended on its coherence. An earlier development that also triggered interest in optical coherence was a series of important experiments by Hanbury Brown and Twiss in the 1950s, showing that correlations between the fluctuations of mutually coherent beams of thermal light could be measured by photoelectric correlation and two-photon coincidence counting experiments. The interpretation of these experiments was, however, surrounded by controversy, which emphasized the need for understanding the coherence properties of light and their effect on the interaction between light and matter.” (Mandel and Wolf, 1995, p. 1)

This further led to a series of studies on light-matter interaction from a coherence perspective, and included analysis of the fluctuation of light by understanding the randomness and the associated statistics of the fluctuations. Mandel, Wolf, Glauber, E.C.G. Surdarshan and many others across the world laid the foundation and connection between optical coherence and quantum optics. What started as a technical development in radio astronomy turned out to be a vital tool in quantum optics.

This blog is part of my course blog on Quantum Optics.

References:

Brown, R. Hanbury, and R. Q. Twiss. ‘LXXIV. A New Type of Interferometer for Use in Radio Astronomy’. Philosophical Magazine 45, no. 366 (1954): 663–82. https://doi.org/10.1080/14786440708520475.

Brown, R. Hanbury, and R. Q. Twiss. ‘Correlation between Photons in Two Coherent Beams of Light’. Nature 177, no. 4497 (1956): 27–29. https://doi.org/10.1038/177027a0.

Hanbury Brown, R., and R. Q. Twiss. ‘A Test of a New Type of Stellar Interferometer on Sirius’. Nature 178, no. 4541 (1956): 1046–48. https://doi.org/10.1038/1781046a0.

Mandel, Leonard, and Emil Wolf. Optical Coherence and Quantum Optics. 1st edn. Cambridge University Press, 1995. https://doi.org/10.1017/CBO9781139644105.

Conversation with Sanjit Mitra

Sanjit Mitra is a Senior Professor at IUCAA, Pune, and explores gravitational wave astronomy. Serving as the science spokesperson, Laser Interferometer Gravitational-Wave Observatory (LIGO)-India and project coordinator, his research focuses on stochastic backgrounds, detector noise, and CMB analysis.

In this episode, we discuss the science and technology behind LIGO and its Indian expansion.

References:

‘Sanjit Mitra – IUCAA’ Accessed 26 March 2026. https://www.iucaa.in/en/faculty-research/sanjit.

‘Sanjit Mitra’. n.d. Accessed 26 March 2026. https://web.iucaa.in/~sanjit/home/About_Me.html.

GW @ IUCAA. Accessed 26 March 2026. https://www.gw.iucaa.in/.

LIGO-India. Accessed 26 March 2026. https://www.ligo-india.in/.

‘‪Sanjit Mitra‬ – ‪Google Scholar‬’. n.d. Accessed 26 March 2026. https://scholar.google.com/citations?hl=en&user=1LVFYJ0AAAAJ&view_op=list_works.

‘LISA: Laser Interferometer Space Antenna’. n.d. Accessed 26 March 2026. https://lisa.nasa.gov/.

Einstein in conversation with Shankland

14th of March is Einstein’s birthday. There is so much written about Einstein, and every time you read about him or a text written by him, there is always something interesting to learn. Recently, I came across a wonderful paper by Shankland, who compiled his conversation with Einstein over a period of ten years and published it in 1962 in the American Journal of Physics. Below are three excerpts from the paper to give you a taste of the conversation. I would urge you to read the conversation in full, and it is a delight.


(Shankland 1963, 1)

“When I asked him how he had learned of the Michelson-Morley experiment, he told me that he had become aware of it through the writings of H. A. Lorentz, but only after 1905 had it come to his attention! “Otherwise,” he said, “I would have mentioned it in my paper.” He continued to say the experimental results which had influenced him most were the observations on stellar aberration and Fizeau’s measurements on the speed of light in moving water. “They were enough,” he said. I reminded him that Michelson and Morley had made a very accurate determination at Case in 1886 of the Fresnel dragging coefficient with greatly improved techniques and showed him their values as given in my paper. To this he nodded agreement, but when I added that it seemed to me that Fizeau’s original result was only qualitative, he shook his pipe and smiled, “Oh it was better than that!” He thought Zeeman’s later precise repetition of this experiment was very beautiful. He seemed really delighted when I mentioned to him how elegant I had found (as a student) his method of obtaining the Fresnel dragging coefficient from his composition of velocities law of special relativity.” (Shankland 1963, 2)

“I asked Professor Einstein how long he had worked on the Special Theory of Relativity before 1905. He told me that he had started at age 16 and worked for ten years; first as a student when, of course, he could only spend part-time on it, but the problem was always with him. He abandoned many fruitless attempts, “until at last it came to me that time was suspect!” Only then, after all his earlier efforts to obtain a theory consistent with the experimental facts had failed, was the development of the Special Theory of Relativity possible. This led him to comment at some length on the nature of mental processes in that they do not seem at all to move step by step to a solution, and he emphasized how devious a route our minds take through a problem. “It is only at the last that order seems at all possible in a problem.”” (Shankland 1963, 2)

“Our conversation then returned to the Michelson-Morley experiment and the Special Theory of Relativity. I could not help feeling that this elegant special theory, the product of his youthful efforts, held the place nearest to his heart. I asked him if he felt that writing out the history of the ;v[ichelson-Morley experiment would be worthwhile. He said, “Yes, by all means, but you must write it as Mach wrote his Science of Mechanics.” Then he gave me his ideas on historical writing of science. “Nearly all historians of science are philologists and do not comprehend what physicists were aiming at, how they thought and wrestled with their problems. Even most of the work on Galileo is poorly done.” A means of writing must be found which conveys the thought processes that lead to discoveries. Physicists have been of little help in this because most of them have no “historical sense.” Mach’s Science of Mechanics, however, he considered one of the truly great books and a model for scientific historical writing. He said, “Mach did not know the real facts of how the early workers considered their problems,” but Einstein felt that Mach had sufficient insight so that what he says is very likely correct anyway.” (Shankland 1963, 4)

There is a lot more to explore in the wonderful conversation paper. Link below.

Shankland, R. S. 1963. ‘Conversations with Albert Einstein’. American Journal of Physics 31 (1): 47–57. https://doi.org/10.1119/1.1969236.

3 Thoughts on Scholarship in an AI-driven Age

One of the important issues to be addressed in recent (AI-driven) times is: how can research scholars acquire knowledge and simultaneously contribute to and communicate with society? Related to this question is: What is the role of scholarship in contemporary times?

Below are three thoughts that I wrote mainly with young researchers in mind. I am hoping that it may find use even among others.

1) Pursuit and utility of knowledge is the primary task of a scholar, and managing the perception of that knowledge is secondary. This means a scholar should use a majority of their time, resources and energy in enhancing scholarly knowledge, and in cases where there is utility, applying that knowledge in the outside ‘noisy’ world. This is your personal knowledge based on your efforts and experiences, and cannot be replaced instantaneously. This also brings uniqueness. Once you have this, you can venture into creating a realistic perception of your knowledge. Remember that learning and researching, to a large extent, are under your control; whereas how the outside world perceives your knowledge is not. Therefore, it would be prudent to pay more attention to learning and doing rather than creating a perception. Note that I am not saying that perception is unimportant. All I am saying is that perception is secondary in importance.

2) One of the key learnings in research and education is that the world is always open to good knowledge and ideas, be it in academia or industry. People are always interested in interacting with and hiring people with a sound knowledge base. It may take a while for somebody to discover your knowledge, but if you have a strong foundation and then go out to the world and interact with it, it is very difficult for the world to ignore you. This means that, having done good work, you should be able to share that work with the outside world. This can be a research paper or an engineering prototype, or any form of science, art or talent that you have. The crucial point here is to first do the hard work and then venture into the sharing of that work.

3) In your work, do not compromise on rigor. If you are a researcher, your first commitment should be towards addressing your scholarly peers or the specialized industry and then broadening your communication. Within scholarly communication, you will have to address questions within the research community. This means you will be basing your work on a large body of knowledge and subjecting yourself to internal and external criticism. This is where rigor comes in handy. Here, rigor does not mean unclear communication. It means to have thought through the questions, nuances and complications of a problem and have a broad and balanced view of the research problem. The general audience sometimes perceives rigorous scholarly communication as filled with jargon and complications. Therefore, it is always better to create two versions of your work: one for your peers and one for the general audience. In the age of AI, the second version is easier to create. Remember that your expertise will be vital in creating the second version for the general audience. That is where you can bring your authenticity and creativity. This can also broaden the scope of your knowledge without compromising your scholarship.

These are a few fleeting thoughts. You can criticize, edit, expand and adapt it to make your own version of it. After all, that is how knowledge moves forward 😊

Raman’s pronouncements..

There is a story going around on Facebook related to C.V. Raman and Nehru, and it makes a reference to Raman’s biography. It describes Raman and Nehru’s interaction in a darkened room at Raman Research Institute. Intrigued by the story, I went back and checked some of the biographies of C.V. Raman, and I could not find that story. If someone could find the exact reference, please let me know. (update on 4th March 2026: I dug up the sources further and found this anecdote in chapter 21 of C.V. Raman: A Biography, by Uma Parameswaran, Penguin Books India (2011). Unfortunately, there is no primary or secondary reference associated with the anecdote.)


Among the biographies, Venkatraman’s ‘Journey into the Light’ is comprehensive and mentions Nehru at least 70 times. It does discuss quite a bit about the interaction between these two powerful people and their differences of opinion. It also highlights their common commitment to science and technology. Raman publicly expressed his opinion on the state of science in India. His pronouncements did not go unnoticed, and the press highlighted them. Raman’s biographer, Venkatraman, addresses the issue of Raman’s criticism: “It should not be assumed that Raman was merely making a series of arbitrary and disconnected pronouncements. On the contrary, they were symptoms of a deep concern he had begun to feel about the way science was being promoted. It seemed to him that in the rush for development, scientific excellence and the objectives of science had begun to take a back seat. Sycophancy was on the rise, and ill-equipped people were being propelled into seats they were not ready to occupy. Everyone paid lip sympathy to the universities, but when it came to funding them, they were generally forgotten. What was worse, mediocrity was slowly allowed to become institutionalized. In retrospect, Raman’s utterances, though harsh, implicitly carried a warning that was unfortunately not heeded. And despite all the pious hopes of that period, the linkages between science and technology in India continue to be quite tenuous.” ([Venkataraman, 1989, p. 488])

Having said that, I should mention that almost all of his biographers mention Raman’s confrontation with a variety of people, starting from his Calcutta days till the end of his life. Subsequent scholarship in social sciences has also highlighted Raman’s issue with gender and caste. In contrast to people like Babha, Saha, and Dhawan, Raman was not an institution builder. He had his limitations, but his commitment to science and its role in society is unquestionable.

As I have written before, Raman was not an easy character to study and understand. He contained multitudes. For sure, he was an outstanding experimental physicist. His knowledge of mathematical physics, especially the classical aspect, was very good, and he utilized it extensively in his work. His scientific biographers, both Venkatraman and Ramaseshan, mention that although he had the aptitude to analyze theoretical frameworks, he was more driven by intuition and generally skimmed over the mathematical aspect of his work. This was also observed by Max Born. He also mentored some excellent scientists, such as K.S. Krishnan, Nagendra Nath, Bhagavatham, Pancharatnam, and G.N. Ramachandran, Anna Mani (one of the few women in his lab), to name a few. Probably the most important feature of Raman as an individual was his can-do spirit and his lifelong drive to do science irrespective of the situation.

My broad lesson from all this is to take the positives from the science and the scientific pursuit of a scientist, and yet, remain aware of the flaws in the character of the human being. After all, course correction is from the benefit of hindsight, and its application is in the present and the future.

Commitment to A Scientific Outlook

On 28th February, we commemorate the first confirmed observation of the Raman effect, dating back to 1928. Raman’s student, K. S. Krishnan (imaged on the right), had an important role in this observation, and the scientific paper associated with Raman scattering has both Raman and Krishnan as the authors (see picture above). Scientific discoveries and inventions happen with constant effort spread over a long duration. It also happens on a strong foundation of knowledge that has already been established.

Raman recognised this and, as he mentions in his talk on scientific outlook, “The happy discoverer in science is invariably a seeker after knowledge and truth working in a chosen field of his own and inspired in his labours by the hope of finding at least a little grain of something new. The commentators who like to consider discoveries as accidents forget that the most important part of a scientific discovery is the recognition of its true nature by the observer, and this is scarcely possible if he does not possess the requisite capacity or knowledge of the subject. Rarely indeed are any scientific discoveries made except as the result of a carefully thought-out programme of work. They come, if they do come, as the reward of months or years of systematic study and research in a particular branch of knowledge.” (Raman, 1951, p. 243)

This, I think, is generally good advice for researchers, especially the younger ones. One cannot over-emphasize the importance of systematic study.

On this commemorative day, it will be good for us, Indians, to commit ourselves to sincere, honest, hard work motivated by a scientific outlook. As Raman mentions, we need to be seekers of knowledge and truth. Not everything may lead to spectacular results, but it will give us a reason for having done something correct and hopefully useful to humanity. In doing so, we may live a meaningful and purposeful life. Science and scientific thinking can have a central role in realizing such a life.

Happy National Science Day to India…and to the world. After all, science is global.

Reference:
Raman, C. V. ‘The Scientific Outlook’. The New Physics – Talks on Aspects of Science by C V Raman, Philosophical Library, New York, 1951. https://doi.org/10.1007/BF02835148.