The Advisory Boar

By Abhijit Menon-Sen <>

Harike survey reporting: responsible journalism at its finest

Someone sent me a link to a story in the Indian Express that creatively distorts quotes extracted from my informal report on Harike to try and make the case that the survey was a waste of time and money. The article is by a Dharmendra Rataul, dated today. I can't figure out if it was published in the newspaper, or only online.

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Missed Opportunities

The Hindu's “Opportunities” supplement on Wednesdays fills the space between job postings with strange articles.

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Not feeling cold

For as long as I can remember, I have resisted being bundled up in woollens during winter. When I was little, I could be bullied into wearing warm clothes, but ever since I was old enough to refuse, my answer to Aren't you feeling cold? has generally been No. Every winter, however, the subject comes up again, and people, often complete strangers, see fit to speculate on or lecture me about low temperatures and my physiology.

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Ulnar neuropathy

For the past several months, I have suffered from a damaged ulnar nerve in my left arm. I'm recovering slowly as the nerve regenerates, but I am no longer impaired by the injury.

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Public Transport in Delhi

Research shows that owning a car makes driving seem cheaper and more convenient than taking public transport. 🙄

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Bloomin' Health: courses in flower therapy

A newspaper article taught me about the “complete healing of a person from within” using flowers energised by the power of the sun, but I'm not sure whether to eat or sniff them.

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The domestic violence problem

A “Talking Point” piece in The Hindu Sunday Magazine explains all you need to know about domestic violence.

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Creepy Camping Companions

I couldn't photograph any peaks or see any birds on our camping trip, so I was able to appreciate the other creatures lurking around us.

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Halving a slice of pie

A few days ago, I bought a slice of Date and Apple Pie from Eatopia.

(Eatopia is a food court at the India Habitat Centre in New Delhi. It is noisy and crowded, but used to have a pretty good bakery. I haven't been there for some years, but Hassath and I happened to be in its vicinity, so we stopped in to pick up a sandwich, a croissant, and a slice of the pie that was once a particular favourite of my father's and mine.)

Hassath was going to eat the sandwich; the croissant was mine. The sandwich was larger, so I finished my croissant first, and was reaching for the pie when a thought struck me: where exactly should I bite it to get no more or less than my fair share?

The slice was too wide to fit in my mouth sideways, so I couldn't try to bite it in half lengthwise (precious crumbs!). I would have to approach this resource-sharing problem pointy-end first, and bite very carefully.

Thinking quickly, I simplified the pie slice to a circular section (assuming that it had uniform thickness, and giving up on the crusty outer edge). It was an eighth of the pie, so its area was πr²/8, and the angle at the vertex was π/4 radians. My fair share (ignoring, in the interests of simplicity, the fact that I clearly deserve a larger piece for forgoing the crust) would thus be an isosceles triangle with half that area; and its height is what I needed to determine.

The area of an isosceles triangle with height l and base d is l×d/2. We know that is equal to half of πr²/8; and we can also express d as 2l×tan(π/8), π/8 being half of the central angle. Thus 2l²×tan(π/8) equals πr²/8, and so l is the square root of πr²/(16×tan(π/8)); in other words, l is r times some constant, which suits us fine.

tan(π/8) gave me a bit of pause, before I remembered that π/4 was a more tractable angle, and tan(θ) equals sin(2θ)/1+cos(2θ). sin(π/4) and cos(π/4) are both equal to 1/√2, so the required tangent is √2−1 ≅ 0.4142. Losing patience, I simplified progressively: 0.4 times 16 is 6.4, which is about twice π, so l ≅ r/√2 ≅ 0.7r. I stuffed the pie into my mouth and bit off a piece that looked about right.

So much for applied math. The pie was awful.

(After I'd finished eating, I realised—looking at the remaining piece—that I had incorrectly assumed that my bite mark would be a straight line. If, instead, I had incorrectly assumed that it would be a section of a circle concentric to the outer edge, I could have saved myself some trigonometry and the answer would have been exactly r/√2. But the pie wouldn't have tasted any better for it.)

On applying for a US visa from Delhi

Speaking of renewing passports and the horrors of international travel, 1999 was also the last time I applied for a US visa (and, I hope, the last time I'll ever need to).

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