Satyendra Nath Bose

Satyendra Nath Bose was an Indian theoretical physicist and mathematician who played a crucial role in the establishment of modern theoretical physics in the country. He was a polymath who worked in different fields such as chemistry, biology, philosophy, literature, fine arts, music, and social science. But, he is most revered for his work in quantum mechanics and his collaboration with Albert Einstein. His paper, “Planck's Law and the Hypothesis of Light Quanta”, laid the foundation of quantum statistics. His contribution to the field was not immediately realised but later on, many scientists built upon his work. Bose-Einstein statistics, as it is known now, was the basis for the prediction of Bose–Einstein Condensate (BEC). BEC was predicted by Einstein in 1924-25 and was created for the first time in the laboratory by various scientists. In 2001, the Nobel Prize for Physics was awarded to scientists who were able to produce BEC in the lab. Bose worked with several distinguished scientists, including Marie Curie, Maurice de Broglie, and Einstein. For his contribution to science, Bose was awarded Padma Vibhushan in 1954 and nominated as a member of the Rajya Sabha.

• SN Bose was born in Calcutta (now Kolkata) on January 1, 1894.
• He did his science intermediate course at Presidency College, Kolkata. There, he was taught by distinguished scientists such as Jagdish Chandra Bose and Prafulla Chandra Bose.
• He did B.Sc honours in mathematics and a M.Sc in mixed mathematics (equivalent to applied mathematics). He was a brilliant student throughout his academic career, obtaining highest marks.
• Later, he taught physics and mathematics at the University College of Science, Calcutta University. In 1921, he joined Dhaka University as a Reader in the Department of Physics, where he taught postgraduate students advanced physics.
• He was a polyglot and knew several languages namely, English, Bengali, French, German and Sanskrit.

Research and Breakthrough Paper

• Satyendra Nath Bose started his research career along with his teaching at the university.
• That time period was an exciting time for physics because quantum theory was making its way into the studies, and some very important papers were written exploring this idea.
• Most of the research work that was available during those times was in the German language. Bose and his college friend Meghnad Sah translated many important papers of prominent scientists such as Hermann Minkowski and Albert Einstein from German to English.
• Bose and Meghnad Saha together published the English translation of Einstein’s paper on General Relativity. It was the first such English translation of the paper.
• In 1918, Bose wrote a paper jointly with Meghnad Saha, which was published in a philosophical magazine. He then wrote papers in the field of mathematics.
• Bose became interested in Planck's Law for Black Body Radiation. This law was given by Max Planck in the year 1900. It described how a black body emits electromagnetic radiation at a thermal equilibrium. Planck arrived at the formula by a logical guess after looking at the data. But this violated the laws of physics.
• Several attempts were made by the scientists to derive the law, but without success. This was because the concepts of classical physics or Newtonian physics do not apply to objects that are very-very small.
• When Bose approached this problem, he considered classical physics unnecessary for deriving the law. He completely eliminated classical physics by making use of the research of Einstein and Compton (Compton's effect). He proved that Plank’s law was nothing but the statistical property of photons (a quanta of radiation).
• Bose sent this paper to the philosophical magazine in England, but they rejected it.
• Then Bose sent a copy of the paper to Albert Einstein with a letter elaborating on his work and seeking his opinion as a fellow scientist. Einstein knew Bose from his previous letter requesting permission to translate Einstein's paper into English.
• Einstein was impressed with Bose’s work so much so that he himself translated the paper to German and sent it to Zeitschrift für Physik magazine, which published the paper “Plancks Gesetz Lichtquantenhypothese” (“Planck’s Law and Light Quantum Hypothesis” in English) in 1924.
• Bose proposed the statistics for the quanta of energy, or photons. Later, Albert Einstein extended this statistics to atoms and generalised it in 1924-25. That is why it came to be known as Bose-Einstein Statistics.

• When atoms or subatomic particles are cooled to an absolute zero temperature (0 Kelvin, -273.15o Celsius or -459.67o Fahrenheit), they start to behave like a single entity or quantum mechanical state. This is the state of matter distinct from other states, namely solid, liquid, gas, and plasma. Hence, BEC is one of the five states of matter.
• BEC was predicted by Albert Einstein in 1924-25 with the help of the groundbreaking research paper of Satyendra Nath Bose. Einstein extended the idea of Bose’s paper to matter (which is now known as Bose-Einstein Statistics) and proposed that by cooling the bosonic atoms to a very low temperature, they could behave in a form of matter.
• In 1995, BEC condensate using rubidium atoms was prepared by Eric Cornell and Carl Wieman. Later that year, BEC condensate of sodium atoms was created by Wolfgang Ketterle. The three scientists got the Nobel Prize for Physics in 2001 for this work.
• BEC has a wide range of real world applications in quantum computing, quantum key distribution for secure communication, etc.

• Bose went to Europe in 1924 and stayed there for two years. There, he met with many scientists.
• With the hope of learning radioactivity techniques, he worked with Marie Curie in her lab. There, he made some measurements of the piezoelectric effect but was not able to work on radioactivity techniques.
• He met Maurice de Broglie, who allowed him to work in his lab with Alexander Dauvillier, de Broglie’s assistant. There, Bose worked on crystallography techniques.
• He later worked in organic chemistry, studying clay minerals by X-ray and radio waves.
• He also worked in the field of Unified Field Theory and published a few papers. But his research in the field came to an end after he heard of Einstein's death.
• He also taught at Shantiniketan, a university established by Rabindranath Tagore. He later returned to Kolkata and became a National Professor (highest honour to a scholar in India) at Calcutta University, a position he held until his death.

• In 1937, Rabindranath Tagore dedicated Visva-Parichay, his only work in science, to Satyendra Nath Bose
• In 1954, he was awarded the Padma Vibhushan by the Government of India for his contribution to science.
• In 1958, he was elected a Fellow of the Royal Society of London.
• He was nominated as a member of the Rajya Sabha.
• He became president of the National Institute of Science and the Indian Physical Society.
• After his death, the S. N. Bose National Centre for Basic Science was established in 1986 in Kolkata by an Act of Parliament.

During his whole career, Satyendra Nath Bose published just 25 research papers. By today's standard, this is not an impressive contribution to the research community. But Bose’s work shows quality which is more important than quantity. The impact of his research work has been huge. He is one of the only scientists whose name is forever linked to the great scientist Albert Einstein. He laid the foundation for modern research in theoretical physics. He played a crucial role in the advancement of quantum physics. His work culminated in the development of Bose-Einstein Condensate, which has a wide range of real-world applications, such as quantum computing. Despite his impressive portfolio of research work, he is not a well known name in India. 2024 will be the 100th year of his groundbreaking research. Young students in the country should be made aware of the revolutionary work of S. N. Bose. His legacy could serve as an inspiration to the whole scientific community for generations.