S.N. Bose in Rajya Sabha

Any physics buff would know Bose-Einstein condensation and the statistics named after them. An interesting fact is Satyendra Nath Bose (SN Bose) also served as a member of the Indian parliament. 

SN Bose was a member of the Rajya Sabha. Notably, he participated in some debates on bills, mainly in the second term, circa 1955 onwards. He was part of the earliest formulation of THE UNIVERSITY GRANTS COMMISSION BILL, 1954. See this link for the bills in which he was involved.

On page 95 of brief biographies of Rajya Sabha members, you will find the following information (snapshot below). These documents are freely available on the Rajya Sabha website and are worth exploring.

Bose also participated in some debates in the Rajya Sabha, mainly regarding education/research. 

Below is an excerpt of his speech related to UGC bill, and shows his interest in the then university/academic system of India (emphasis added) :

  It has, of course, been suggested that this particular Commission would be able to solve the problem of education in this country. I may, however, point out that in this task we will ultimately have to depend upon the responsible people that are in charge of education inside the Universities. I also know, Sir, that every teacher in our country is alive to his responsibility, and the corporate bodies that we have set up in our land are also serious about their tasks. I do not feel, Sir, that the standard of our universities has gone down to a very ludicrous level. I do not feel so, because I remember the long list of persons that have been turned out by these universities who had served the national cause, and who have been and who still continue to be the leaders of thought in our country. We also remember. Sir, that in many of these universities, there are young people and workers who have achieved fame and distinction, who have contributed substantially to the cause of learning, and who have made the name of India respected in different lands. Therefore, Sir, you need not have any misgivings about the way in which, work is being done in our universities. All that is wanted is that you should be generous, and you should set up an efficient machinery  which should be able to get in touch with the people who work at different centres, and should find out what they need. And you should be able to supply those needs in the form of grants, which may either be given out of the Consolidated Fund of the Government or out of the fund set apart for this purpose, which would be administered by the Commission. 

As you can observe, SN Bose is making a case for increased funding to the Indian research community and is emphasizing the availability of excellent human resources in universities. As researchers in India, we must ask ourselves whether we have lived up to his confidence and effectively addressed these issues over the past several decades. I believe we have not. Bose’s optimism motivates us to relook at our system and self-reflect on pursuing scientific and technological research in India. A good starting point is to ask for ‘ease of doing research and teaching’. 

A few Indian scientists of the past, including Meghnad Saha and MGK Menon, were also members of the Indian parliament. Still, this representation needs to be improved, as discussed by my colleague MS Santhanam. Scientists inclined to take politics to influence society must openly express their opinions on policies related to science and technology. If they do get elected to the office, it is their imperative to actively participate in parliamentary debates and ask and address relevant questions, especially about education and research.

After all, the foundation of democracy is based on ‘questions and answers’, and interestingly, that is also the foundation of scientific method.

J.C. Bose and the measurement of refractive index

Image : Wikicommons

How do you determine the refractive index of a material which is not transparent?

In 1895, J.C. Bose addressed this question experimentally using ‘electric rays’, which we currently know as microwave radiation!

The citation of the paper is

Bose, J. C., I. On the determination of the indices of refraction of various substances for the electric ray. I. Index of refraction of sulphur. Proceedings of the Royal Society of London, 59(353–358), 160–167. https://doi.org/10.1098/rspl.1895.0069

Below is the title of the paper that was communicated to the Royal Society via Lord Rayleigh, who was an authority on optical concepts Bose was using.

His experiment used the microwaves’ total internal reflection and extracted the samples’ refractive index through Brewster’s angle.

Bose beautifully describes his method as follows :

The angle of incidence is slowly decreased till the critical value is reached. At this point the ray is all at once refracted into the air, making an angle of 90° with the normal to the surface. If a receiver be fixed against the side of the semi-cylinder at II, it will now respond to the refracted radiation.

Below is the diagram depicting the same principle :

And the detailed description is as follows:

The refracting substance is cut out or cast in the form of a semi¬ cylinder, and mounted on the central table of a spectrometer; the electric ray is directed towards the centre of the spectrometer, and its direction is always kept fixed. It strikes the curved surface and passes into its mass without any deviation. It is then incident on the plane surface of the semi-cylinder, and is refracted into the air beyond.

The apparatus design was also interesting, and the diagram below depicts what we nowadays call the microwave transmitter (indicated as radiator, R) and receiver (indicated as Coherer, C).

If you read the paper completely, the details of experiments are described meticulously, and the attention to detail is remarkable.

So, he determines the refractive index of sulfur using this method and ends up with a value of 1.734, which is quite accurate even by today’s standards (the value is upwards of 1.7 and depends on the wavelength of light). Notice that the measurement was made to the accuracy of three decimal places, which is impressive. Below is a set of data for which the value of the refractive index was determined.

Now compare this to the modern measurement (see below data from around 1985) of refractive index based on more sophisticated methods, and you will see the matching is reasonably good at higher wavelengths close to 1 micron. (Note that Bose’s measurements was at higher wavelength than shown below)

Data from: Icarus. Volume 64, Issue 3, December 1985, Pages 368-374; https://www.sciencedirect.com/science/article/abs/pii/0019103585900612

J.C. Bose was a creative scientist; the above example is just a small illustration of his capabilities as an experimentalist.

Now, with this inspiration, let me head back to my lab to do some experiments :-)

ps: A video to go with this blog (updated on 17th Apr 2025)

Electron Microscopy and Optical Holography: some notes from history

Since the 16th century CE, improving the limits of optical resolution has become an essential technical goal in optics research, and it continues to challenge us even today. When they were introduced, optical microscopes opened a new world for humans to observe, learn and eventually control matter at microscopic scales. A logical progression in this thought was to extend the resolution limit to the atomic scales unavailable to optical microscopes. Enter the ‘electron’ microscope. They changed the game entirely and paved the way to visualize matter at the atomic scale.

Electron microscopes were invented in the 1930s. When they were built in some laboratories, there was considerable public interest in understanding these “advanced” tools, as witnessed by a short but interesting article in the September 1940 edition of Popular Mechanics.

Sept 1940: Above is an image and description of one of the earliest electron microscopes published in Popular Mechanics

Reference: Popular Mechanics ~ 1940. n.d. Accessed January 7, 2024. http://archive.org/details/PopularMechanics1940.

The article speculates

First applications of the electron microscope are expected to be in biological and industrial research.

This is interesting because electron microscopes were still in their infancy, and the working principles were explored for better quality images and sample durability.

The origins of the electron microscope have an interesting history and were inspired by optics (for an interesting commentary, see Freundlich, Martin M. 1963. “Origin of the Electron Microscope.” Science 142 (3589): 185–88. https://www.jstor.org/stable/1712183). The first demonstration of a working microscope was by Ruska and Knoll (Z. Tech. Phys., 12 (1931)), and the conceptual foundations date back to the late 1890s. Ruska was eventually awarded a Nobel prize for his work on electron optics and the invention of the electron microscope in 1986.

As with any development in science and technology, an idea becomes a seed to another idea. In the case of electron microscopy, it led to some early motivations behind the invention of optical holography by Dennis Gabor, which eventually fetched him a Nobel Prize in 1970.

Dennis Gabor was also inspired and interested by the invention of electron microscopes. He played a critical role in formulating the problem of resolution limit, which further led to the invention of holography. To quote his Nobel lecture :

Let us now jump a century and a half, to 1947. At that time I was very
interested in electron microscopy. This wonderful instrument had at that time
produced a hundredfold improvement on the resolving power of the best light
microscopes, and yet it was disappointing, because it had stopped short of resolving atomic lattices. The de Broglie wavelength of fast electrons, about
l/20 Ångström, was short enough, but the optics was imperfect. The best
electron objective which one can make can be compared in optical perfection
to a raindrop than to a microscope objective, and through the theoretical
work of O. Scherzer it was known that it could never be perfected.

Interestingly, Gabor started his work in Germany but had to move out of the country due to the political situation. As he mentions in his biographical note :

In 1933, when Hitler came to power, I left Germany and after a short period in Hungary went to England. At that time, in 1934, England was still in the depths of the depression, and jobs for foreigners were very difficult. I obtained employment with the British Thomson-Houston Co., Rugby, on an inventor’s agreement. The invention was a gas discharge tube with a positive characteristic, which could be operated on the mains.

He stayed back in England and continued his work. The important aspect is that the development of electron microscopy eventually led to some fundamental experiments in optical holography. To quote Gabor’s biographical note :

The years after the war were the most fruitful. I wrote, among many others, my first papers on communication theory, I developed a system of stereoscopic cinematography, and in the last year, 1948 I carried out the basic experiments in holography, at that time called “wavefront reconstruction”. This again was an exercise in serendipity. The original objective was an improved electron microscope, capable of resolving atomic lattices and seeing single atoms. Three year’s work, 1950-53, carried out in collaboration with the AEI Research Laboratory in Aldermaston, led to some respectable results, but still far from the goal. We had started 20 years too early. 

The general notion in optics is that experiments in the visible light frequencies led to developments in electron microscopy. In the case of optical holography, at least in the initial stages of its invention, electron microscopy played a critical role. Developments in electron optics led to some fundamental questions in optical wavefront reconstruction. This further led to optical holography.

This reminds me of a quote attributed to Buckminster :

How often I found where I should be going only by setting out for somewhere else.

A capitalistic Galileo ?

Some books on the history of thermodynamics

Müller, Ingo. 2007. A History of Thermodynamics: The Doctrine of Energy and Entropy. Springer Science & Business Media. https://www.google.co.in/books/edition/A_History_of_Thermodynamics/u13KiGlz2zcC?hl=en&gbpv=1&printsec=frontcover.

Truesdell, C. 2013. The Tragicomical History of Thermodynamics, 1822–1854. Springer Science & Business Media. https://www.google.co.in/books/edition/The_Tragicomical_History_of_Thermodynami/3EjaBwAAQBAJ?hl=en&gbpv=1&printsec=frontcover.

John Michell and ‘dark stars’

November 1783,
John Michell published a paper on ‘dark stars’.

This was kind of a preamble to the concept of black holes & interestingly, was based on Newton’s corpuscular theory of light and the slowing down of light due to gravity!

See this article for details:

https://aps.org/publications/apsnews/200911/physicshistory.cfm?fbclid=IwAR18kT6v-zMtqT5B3udIHxb0gjDYkv5AyFqHDLd2lEZ41-QecKhVG-llrhY

Part of the original paper (the beginning) is reproduced below :

The first few lines of Michell’s 24-page paper elaborate on his idea. As you may observe, he makes a remarkable connection between the velocity of light and the measures related to stars (distance, magnitude, etc.)

Kumar Patel and CO2 laser- Baramati-Pune to Bell Labs

Happy Deepavali: let’s celebrate (laser) light! Did you know there is a connection b/w Baramati, Pune city & the first-ever CO2 lasers? Kumar Patel, the inventor of one of the most powerful lasers, was born in Baramati & did his BE at the College of Engineering, Pune!

Chandra Kumar Naranbhai Patel had an illustrious career. From Pune, he moved to Stanford University for his PhD and then worked at Bell Labs, where he created his CO2 laser. See him describe the invention:

In Nov 1964 (around the time of the Diwali festival :)), he published his invention: https://journals.aps.org/pr/abstract/10.1103/PhysRev.136.A1187

Wikipedia has a good profile of his work, including a video :

https://en.wikipedia.org/wiki/C._Kumar_N._Patel

Kumar Patel went on to win many laurels, including US President’s National Medal of Science. https://www.nsf.gov/od/nms/recip_details.jsp?recip_id=270

Kumar was a rare engineering scientist who also served as the president of the American Physical Society in 1995.

https://www.aps.org/about/governance/presidents.cfm

One of the reasons to celebrate Diwali is the move from darkness(ignorance) to light(knowledge). I hope humanity moves toward peace, knowledge and harmony with nature guided by compassion and science. Baramati-born Kumar Patel has shown us one of the ways.

Kannada – ನಿಮಗೆಲ್ಲರಿಗೂ ದೀಪಾವಳಿಯ ಶುಭಾಶಯಗಳು

Marathi – तुम्हा सर्वांना दीपावलीच्या हार्दिक शुभेच्छा

Sanskrit – सर्वेभ्यः दीपावली शुभकामना

Hindi – आप सभी को दीपावली की शुभकामनाएँ

I wish you all a happy Deepavali.

Curie and Raman – born on this day

Marie Curie (7 November 1867 – 4 July 1934) and CV Raman (7 November 1888 – 21 November 1970) were born on this day. Both were extraordinary scientists and strong characters.

Marie Curie led an extraordinary life, and her dedication to science was unparalleled. She led a tough life in a male-dominated society and became a great scientist. Previously, I have written about her in one of my blogs on lab writing:
https://backscattering.wordpress.com/2018/11/11/expression-as-exploration/

CV Raman was an outstanding experimentalist and trained many students. He had his faults but led an astonishing scientific life, and linked are a couple of talks on his scientific biography that I have given:https://backscattering.wordpress.com/2022/03/18/talks-on-c-v-raman-youtube-links/

Scientists are human beings. For me, understanding their scientific life history in the context of their society & environment is fascinating. There is always something to learn from their past, not only from their achievements but also from their mistakes.

Keeps me humble!