Prof. AK Raychoudhri, one of the doyens of the Indian Physics Community, passed away in June 2005. He is probably one of the most under-recognised scientists of his time. Frankly, I had not heard about him till I learnt some Gen.Relativity. The famous “Raychoudhry Equation” is a crucial tool to understanding GR and played an important part in the famous work of Hawking and Penrose on Singularity Theorems. It is these theorems and the interest on compact objects that re-ignited GR research in the 70s. For those who are familiar with some GR, I would suggest that you read Prof.Dadich’s paper on the Raychoudhry equation: gr-qc/0511123

The Telegraph carried an excellant tribute to this great man. The sad part is that there was very little media attention devoted to his passing away. Here are a few abstracts from that piece :

[..]For the first time, singularities seemed inevitable in GTR, and could no longer be argued away as being artifacts of special properties of specific solutions of the Einstein equation. Again, not a result the master would have rejoiced over[..]

Here, the master is Einstein.

The central theme of the singularity theorems is how a singularity is an inevitable feature of solutions to Einstein’s GR. Raychoudhri’s equation gave hints to this property of Einstein’s equations. But the complete theorems had to wait till Hawking and Penrose.

[..]Why did Raychaudhuri himself not arrive at the singularity theorems when he possessed the key tool more than a decade in advance? The answer: he was pursuing a different programme — that of finding a spacetime free of singularities. That programme did not succeed, but careful perusal of his efforts once again bears testimony to his original approach and commitment to the subject[..]

[..]He submitted a thesis based on his work on the Raychaudhuri equation for a DSc in physics, and in 1959 was awarded the degree on the glowing recommendation of none other than John Archibald Wheeler*. Despite this, an application for a promotion to a higher position at the IACS was turned down by the authorities on some flimsy pretext[..]

After this, he joined the Presidency College, Kolkatta. He taught there for a long time. The most remarkable thing about AKR is that he taught undergrad students at Presidency. I do not know of many top-class Indian Physicists teaching at the Indian Universities. I have personally heard many of his students (now physics profs) talking about how inspiring his classes were. Prof.Dadich also lists some of AKR’s former students: Ashoke Sen, S.Bhattacharya (current TIFR Director),CV Vishveshwara,JV Narlikar and Probir Roy .

The last few lines from the Telegraph probably sums up his life in the best fashion :

[..] he was a total academic, a rarity these days. To paraphrase Einstein’s well-known remark about Mahatma Gandhi, future generations of Calcuttans will scarcely believe that such a physicist lived among us, sharing his best with so many.

This post would have served its purpose if it made ARK and his work known to a much larger audience.

*For those who didnt know, Wheeler is a highly acclaimed Theo.Physicist. He is also a well known Gen. Relativist. Feynman and some great relativists like Misner,Thorne,Wald were his PhD students.