Letters

Amateur mathematics

I was dismayed to read Bibek Debroy's piece on Vedic mathematics (Down To Earth, May 31, 1993). The alleged Vedic mathematical sutras are amateurish and contrived. Take the specific example of multiplying 92 by 93. The procedure works only when the numbers are between 90 and 100! In fact, a survey of all the examples that illustrate the Vedic sutras shows that the numbers used are invariably close to 100, 1,000 or have their individual digits close to 0 or 10. The reason becomes obvious if you apply a little algebra. The procedures are all simple tricks which do not work except on such carefully doctored examples. They have no universal validity.

The other trick is to illustrate a concocted example and make sweeping generalisations about the "superiority" and "deep insights" provided by the sutras. Any high school student with a bent towards mathematical puzzles can tinker with numbers and remainders. But to suggest that such number play "when generalised (leads) to the remainder theorem" is absurb.

Professor Debroy replies:
The article does not explain all the principles of Vedic mathematics because detailed explanation would be beyond the scope of a magazine. The article was written to introduce the topic to readers.

There are methods in Vedic mathematics to multiply numbers which are not close to 100, 1,000, or 10,000, but these require some more elaborate explanation. For example, 64 and 55 can be multiplied by the Vedic method to get 3,520.

Readers who wish to know more about Vedic mathematics can look up A Modern Introduction to Ancient Indian Mathematics by T S Bhanu Murthy. ...

Not correct

I find I have been erroneously quoted in a report on the BELLE project (Down To Earth, May 31, 1993). You have mentioned that "... his counterpart at IGIDR believe TERI was more interested in 'hijacking' the project. This is totally erroneous reporting. I have neither mentioned nor implied this anywhere.

My write-up centres around the fallacy of PACER's decision to reject the project and criticism of PACER's decision-making process.

J P PAINULY
Associate Professor
Indira Gandhi Institute of Development Research Bombay Apropos of the report on the BELLE project, let me set the record straight:

• At no stage did I state to your reporter that "we saw to it that BELLE did not get PACER's approval. I only made it clear that I could not have gone along with lending my support to a project that I found was not economically viable. I mentioned specifically the cost of $12, at which compact fluorescent lamps (CFLs) were planned to be imported from Phillips in addition to customs duty, which at that time was prohibitive. Even today I cannot support a proposal that relies on household uses of CFLs as opposed to first tackling technical questions and marketing to commercial establishments such as hotels, which have much longer lighting hours and hence, would require priority on economic grounds.

• The name of the second manufacturer that was drawn into the BELLE project at our suggestion was not Surya Roshni Limited, as you have stated, but Apar Limited. As far as I know, at no point did they press for TERI's inclusion in the project, nor was TERI interested in being included in a project that we did not see as justified.

Finally, PACER was set up to accelerate commercial energy research, not to support the marketing efforts of a single manufacturer without technology development in keeping with local operating conditions or, at least, ensuring manufacture indigenously.

R K PACHAURI
Director, Tata Energy Research Institute
New Delhi 110 003

News Editor Anupam Goswami replies:

The comment made about TERI and other institutions being interested in the hijacking of the BELLE project was inadvertently credited to Dr Painuly. It was made by other participants of the BELLE consortium.

While the errors pointed out by Dr Pachauri are regretted, several sources involved with PACER have confirmed TERI's pivotal role in the scuttling of the BELLE project. ...

No to BST

In the article relating to bovine somatotropin (BST) hormone (Down To Earth, May 31, 1993) . G P Talwar argues that there is no evidence to suggest that public health can be affected by consumption of milk from hormone-treated cows. This is based on the fact that some people have drunk it without knowing and have showed no symptoms.

But there are so many other powerful arguments for not using it as a method of increasing milk production. For example, though milk is a nutritious product, except for infants, humans do not need cow's milk. It is important that we start from here because we as milk producers must be sure that we hold on to this share of the food market. We must ensure that consumers continue to perceive milk as a wholesome nutritious product to give to young children....

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