Chandrashekhar Limit: When does a white dwarf star collapse?

The Chandrasekhar Limit can be expressed as the maximum nonrotating mass which can be supported against gravitational collapse by electron degeneracy pressure. This is commonly understood to be about 1.4 solar masses (i.e. 1.4 times the mass of the sun or about 333,000 times greater than the mass of the earth).

The Chandrashekhar Limit is an upper limit for the mass of a white dwarf. It has been observed that so-called main-sequence stars with a mass greater than about 8 solar masses are unable to lose enough mass to form a stable white dwarf at the end of their lives, and so they form either a neutron star or a black hole.

A brilliant and gifted physicist, Subrahmanyan Chandrasekhar (Nobel, Physics, 1983) had a very public disagreement about what became known as the Chandrashekhar Limit with Arthur Stanley Eddington (while Chandrashekhar was a junior scientist at Cambridge). Eddington ridiculed Chandrashekhar by terming his work "stellar buffoonery". Chandrashekhar had the last laugh, and a Nobel, in 1983. The bitterness surrounding this event contributed to Chandrashekhar moving to the University of Chicago. He returned to this important work only after about three decades.

NASA has honoured him by naming the third of its four "Great Observatories'" after Chandrasekhar. The Chandra X-ray Observatory was launched and deployed by Space Shuttle Columbia on July 23, 1999.

One episode of the BBC Radio 4 series "Test tubes and tantrums" considers this controversy (Chandrashekhar vs Eddington) - podcast available at: http://www.bbc.co.uk/radio4/science/testtubesandtantrums.shtml

Dulce et decorum est pro patria mori

My friend, you would not tell with such high zest
To children ardent for some desperate glory,
The old Lie; Dulce et Decorum est
Pro patria mori.

Wilfred Owen (composed 1917)

So, sad. Tangmarg, Baramula, Kashmir and the two young officers killed today (Major KP Vinay and Major DR Raman). Major Vinay was due to be married later this month. So many other young lives blighted by war ... We have been here before.

Burma, India and Realpolitik

FT, 30th Sep 07 "India pressed to take lead on democracy":

In private, Indian officials reject criticism. “We’re not bothered about criticism of our relations with Myanmar, given the west’s record in supporting military governments in our neighbourhood,” said one. “We’re not the only democracy that works with generals.”

Brahma Chellaney, a security affairs expert, concurs: “The US is going along with the fraudulent elections in Pakistan while wanting India to do more on Burma. India applies the same principle to Burma as to Pakistan: while it would like democracy to flourish, it will not make it the central plank of its foreign policy in either country.”

Paul Simon on DiMaggio: A metaphor for our times?

What is the larger significance of DiMaggio's death? Is he a real hero? Let me quote the complete verse from ''Mrs. Robinson'':

Sitting on a sofa on a Sunday afternoon
Going to the candidates' debate
Laugh about it, shout about it
When you've got to choose
Every way you look at it you lose.

Where have you gone, Joe DiMaggio?
A nation turns its lonely eyes to you
What's that you say Mrs. Robinson
Joltin' Joe has left and gone away.

In these days of Presidential transgressions and apologies and prime-time interviews about private sexual matters, we grieve for Joe DiMaggio and mourn the loss of his grace and dignity, his fierce sense of privacy, his fidelity to the memory of his wife and the power of his silence.

'The Silent Superstar' By Paul Simon
New York Times, March 9, 1999

How mathematical should economics be?

Manmohan Singh on economics (LSE, 2006):

In more recent decades we see excessive specialization in social sciences, and economists fancy themselves to be social engineers and technocrats. But we must never forget that economics began, after all, as political economy. Economic policy making has always involved political choices since it has political consequences. IG belonged to a generation that recognized this ground reality. He knew that the choices our economists were recommending for adoption by our country had to be marketed in the political marketplace of a functioning democracy. It was not enough that these choices were rational, or that their costs and benefits could be measured. It was not enough that the arguments were intellectually consistent or were mathematically tested. In a democracy such choices had to be also politically defendable and acceptable.

Rule of law

In modern democracies, the notion of rule of law is paramount. Even when many governments may not fully adhere to its precepts, our rulers often simply pay lip service to its ideals and to the defence of republican values. Two influential comments on the notion of rule of law are the following:

1. Thomas Paine (Common Sense, 1776):

But where, say some, is the king of America? I'll tell you Friend, he reigns above, and doth not make havoc of mankind like the Royal of Britain. Yet that we may not appear to be defective even in earthly honors, let a day be solemnly set apart for proclaiming the charter; let it be brought forth, placed on the divine law, the word of God; let a crown be placed thereon, by which the world may know, that so far as we approve of monarchy, that in America the law is king. For as in absolute governments the king is law, so in free countries the law ought to be king; and there ought to be no other. But lest any ill use should afterwards arise, let the crown at the conclusion of the ceremony be demolished, and scattered among the people whose right it is.

2. John Adams (1735-1826: framer of the Massachusetts Constitution. Quote below from The First Part, Art. XXX (1780))

In the government of this commonwealth, the legislative department shall never exercise the executive and judicial powers or either of them: the executive shall never exercise the legislative and judicial powers, or either of them: the judicial shall never exercise the legislative and executive powers, or either of them: to the end it may be a government of laws and not of men.

Another gem from Paine (Common Sense, 1776):

A long habit of not thinking a thing wrong, gives it a superficial appearance of being right, and raises at first a formidable outcry in defense of custom.

Bulleh Shah, Carvaka and Sufi Poetry

I have been struck by the beauty, wit, cadence and deep rooted philosophical questions within some poetry composed by Sufi poets. It is a salutary lesson that the Sufi school - celebrating the syncretic and assimilative traditions of Islam, Sikhism and Hinduism - was attacked, vilified and ultimately replaced by the more strict Wahabi school, which has contributed to ideas such as the so-called ‘clash of civilisations’ and much more irrationality, bias and intolerance. Sufi music has, of course, been popularised by the likes of Nusrat Fateh Ali Khan, Junoon and Rabbi Shergill. I was struck by the profound philosophical undertones within Rabbi’s ‘Bulla ki Jana’which has become a very well known song.

It is a great tragedy that Pakistan has officially accorded national language status to Urdu, English and Arabic - none of which are native to Pakistan, while Punjabi in Pakistani Punjab is merely a spoken language now. In India, matters are no better. Punjabi is highly vernacularised and looked down upon by the elites who prefer highly Sanskritised Hindi (and English) and regard Punjabi mainly as a rough, unadorned language, thus ignoring its contributions to India’s literature and culture, and in maintaining India’s tradition of oral renditions of literary works. Interestingly, admirers of Sufi poetry in Pakistan are pinning their hopes for the defence and preservation of the Punjabi language on the efforts of the Sikh minority within Pakistan.
What is undeniable is the influence of Urdu and Persian syncretic influences on the Punjabi of this period (late 17th - early 18th century).

This period was also the age of Enlightenment and the renaissance in Europe, which brought to the fore the ideas of Kant, Rousseau and Voltaire. In my view, in terms of the intriguing, perplexing, existentialist questions posed by other philosophers, Bulleh Shah’s poetry holds its own. The Sufi poetry of Sultan Bahu, Waris Shah and Shah Hussain is well known - it is only recently that Bulleh Shah has been rediscovered. Bulleh Shah’s poetry brings out another interesting aspect - the influence of the Hindu Carvaka (pronounced Charvaka) or the Lokayata school of belief dating c. 600 BC (qhich mainly questioned the existence and onmipotence of god). Like the Carvaka school and its attack on Brahmanical excesses and superstition, Bulleh Shah’s poetry includes direct attacks on anyone claiming control over religion, including comparing religious clerics to barking dogs and crowing roosters. India's Nobel laureate in economics, Amartya Sen, was engaged in discussion with his grandfather. Amartya Sen declared that since he was Marxist (and consequently atheist) and did not follow any particular school of Hindu faith, he was not Hindu at all. His grandfather’s reply: ‘Yes, you are a Hindu - of the Carvaka school.’ This school was redicovered through a study of Madhavacharya’s Sarva-Darsana-Sangraha [c. 1400 AD]. The following gives a flavour of Lokayata beliefs. The Hindu sage Brihaspati, regarded by some as the founder of the Carvaka school,
argues as follows:



Roughly translated, this Sanskrit quotation goes as follows: As long as you live, live happily; take a loan and drink ghee. After a body is reduced to ashes, where will it come back from?