Meghnad Saha | |
|---|---|
 | |
| Born | (1893-10-06)6 October 1893 |
| Died | 16 February 1956(1956-02-16) (aged 62) |
| Alma mater | Dhaka College Dhaka Collegiate School |
| Known for | |
| Spouse | Radha Rani Saha |
| Scientific career | |
| Fields | Physics,astrophysics |
| Institutions | |
| Academic advisors | |
| Doctoral students | |
| Member of Parliament, Lok Sabha | |
| In office 3 April 1952 – 16 February 1956 | |
| Preceded by | Position established |
| Succeeded by | Ashoke Kumar Sen |
| Constituency | Calcutta North West |
| Personal details | |
| Political party |  Revolutionary Socialist Party (India) |
| Signature | |
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Meghnad Saha (6 October 1893 – 16 February 1956) was an Indianastrophysicist and politician who helped devise the theory ofthermal ionisation. HisSaha ionisation equation allowed astronomers to accurately relate thespectral classes ofstars to their actual temperatures.[1][2][3]
Meghnad Saha was born on 6 October 1893 to a lower casteBengali Hindu family in the village ofSheoratali inGazipur, then part of theDacca district of theBengal Presidency (nowBangladesh).[4][5] He was the fifth of eight children born to Jagannath Saha, a poor shopkeeper, and his wife, Bhubaneshwari Devi.[6] Due to the superstitious religious ideologies of the orthodox haughtyBrahmins of the time and his childhood and career experiences ofcasteism, Saha developed a hatred forcaste system from a young age.[7]
During his youth, he was forced to leaveDhaka Collegiate School because he participated in theSwadeshi movement.[8] After that he joinedK. L. Jubilee High School & College. He earned hisIndian School Certificate fromDhaka College.[8] He was also a student at thePresidency College, Kolkata andRajabazar Science College CU. Saha faced discrimination from other students due to his caste; when he was at theEden Hindu Hostel, communal students objected to him eating in the same dining hall as them.[1][9]
He was a professor atAllahabad University from 1923 to 1938, and thereafter a professor and Dean of the Faculty of Science at theUniversity of Calcutta until his death in 1956. He became aFellow of theRoyal Society in 1927.[10] He was president of the 21st session of theIndian Science Congress in 1934.[11]
Amongst Saha's classmates wereSatyendra Nath Bose,Jnan Ghosh andJnanendra Nath Mukherjee. In his later life, he was close to Amiya Charan Banerjee.[12][13]
Saha's study of thethermal ionisation ofelements led him to formulate what is known as theSaha ionisation equation. This equation is one of the basic tools for interpreting thespectra of stars. By studying the spectra of stars, one can find their temperature and using Saha's equation determine the ionisation state of the elements making up the star. This was extended byRalph H. Fowler andEdward Arthur Milne. Saha had previously reached the following conclusion on the subject:
It will be admitted from what has gone before that the temperature plays the leading role in determining the nature of the stellar spectrum. Too much importance must not be attached to the figures given, for the theory is only a first attempt for quantitatively estimating the physical processes taking place at high temperature. We have practically no laboratory data to guide us, but the stellar spectra may be regarded as unfolding to us, in an unbroken sequence, the physical processes succeeding each other as the temperature is continually varied from 3000 K to 40,000 K.[14]
Saha also invented an instrument to measure the weight and pressure of solar rays.
Meghnad Saha helped to establish several scientific institutions, including thePhysics Department atAllahabad University inUnited Provinces (nowUttar Pradesh) and theInstitute of Nuclear Physics (nowSaha Institute of Nuclear Physics) inKolkata. He founded the journalScience and Culture and was the editor until his death.[15] He was the leading figure in organising several scientific societies, such as the National Academy of Science (1930), theIndian Physical Society (1934), and theIndian Institute of Science (1935). He was the director atIndian Association for the Cultivation of Science from 1953 to 1956. TheSaha Institute of Nuclear Physics, founded in 1943 in Kolkata, is named after him.[16]
Saha stood as a candidate for North-West Calcutta in the1951 Lok Sabha election. He ran as a member of the Union of Socialists and Progressives,[17][18][19] but maintained his independence from the party. His goal was to improve the planning of education, industrialisation, healthcare, and river valley development. He was up againstPrabhu Dayal Himatsingka. Due to low funding for his campaign, Saha wrote to the publisher of his textbookTreatise on Heat to ask for an advance of ₹5000. He was elected by a margin of 16%.[20]
Saha participated in the areas of education, refugees, rehabilitation, atomic energy, multipurpose river projects, flood control, and long term planning. In the bookMeghnad Saha in Parliament, Saha is described as:
"Never unduly critical... forthright, so incisive, so thorough in pointing out lapses that the treasury bench was constantly on the defensive. This is brought out by the way he was accused of leaving his laboratory and straying into a territory not his own. But the reason why he was slowly drifting towards this public role (he was never a politician in the correct sense of the term) was the gradually widening gulf between his dream and the reality—between his vision of an industrialised India and the Government implementation of the plan."[21]
Saha was the chief architect of river planning inIndia and prepared the original plan for theDamodar Valley Project. His own observation with respect to his transition into government projects and political affairs was:
Scientists are often accused of living in the "Ivory Tower" and not troubling their mind with realities and apart from my association with political movements in my juvenile years, I had lived in ivory tower up to 1930. But science and technology are as important for administration now-a-days as law and order. I have gradually glided into politics because I wanted to be of some use to the country in my own humble way.[22]
Saha married Radha Rani Saha on 16 June 1918. They had a total of 7 children: 3 sons and 4 daughters.[23]
Saha died on the way to the hospital on 16 February 1956 after gettingcardiac arrest. He was going to the office of thePlanning Commission in theRashtrapati Bhavan. It was reported he had been dealing withhypertension for ten months prior to his death.[26] His remains werecremated at theKeoratola crematorium, Kolkata the following day.[27]
Born into a 'lower' caste family, he went on to become a polymath, politician, and pioneer scientist who made several seminal contributions to the world of physics.
Although the list is in some respects unrepresentative of the widening range of science in late-colonial India, it reflects a growing social and regional diversity. Between 1924 and 1944 the Royal Society elected as Fellows Meghnad Saha, from a low-caste family in east Bengal, S. S. Bhatnagar (a Kayastha) and Birbal Sahni from Punjab, Homi Bhabha, a Parsi from Bombay, C. V. Raman, a Tamil Brahmin, his nephew S. Chandrasekhar, and K. S. Krishnan, Raman's associate and successor as Palit Professor of Physics, also originally from south India.
Even though he later came to be known as an atheist, Saha was well-versed in all religious texts— though his interest in them was purely academic.
