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S Chandrasekhar: the student who took on the world's top astrophysicist

Le 23 novembre 2017, 09:07 dans 教育 0

In the 1930s the rarefied world of science was ripped apart by a controversy that was to have devastating consequences for the development of astrophysics. It began when an Indian student called Subrahmanyan Chandrasekhar (Chandra) decided to work out what would happen if Einstein's special theory of relativity was applied to the processes that went on inside stars. This step was important because particles inside stars travel at speeds close to that of light, a situation where Einstein's theory must be used.

Pencil in hand, 19-year-old Chandra did some calculations. At the time, scientists assumed that when a star burned up the last of its fuel, it would turn into a ball of cinders and go cold - become a white dwarf star. Chandra's mathematics showed that a white dwarf much heavier than the sun could not exist, but would undergo an eternal collapse into a tiny point of infinite density, until it slipped though a crevice in space and time, from which nothing could escape, not even light. It was the first irrefutable mathematical proof that black holes - as they were later dubbed - had to exist.

Chandra made his discovery while on his way to study in the greatest scientific powerhouse of the day, Trinity College, Cambridge. He assumed the community there would welcome him and his discovery with open arms. He had grown up in a free-thinking Brahmin household in Madras and had been recognised as a prodigy from an early age. He had already completed his undergraduate degree and had published several scientific papers. The daily reminders that India was under the yoke of the British Empire rankled him and science seemed a way to show that he was at least equal to the colonial masters. His uncle, CV Raman, had been the first Indian to win the Nobel prize in physics. Chandra hoped that he might win one too.

At Cambridge his hopes were dashed. Scientists there ignored his discovery. Cast down by the dank fens and dreary weather, utterly unlike the welcoming warmth of south India, he gave way to depression. But he pressed on and in 1933, completed his doctorate. He also won a fellowship to continue his work at Cambridge. Buoyed by these successes, he returned to his research on the fate of the stars. To his surprise the great Sir Arthur Stanley Eddington, doyen of the astrophysical world, took to visiting him frequently to see how he was getting on.

Eddington was at the peak of his fame as a scientist, philosopher and populiser of the science. He had made Einstein's general theory of relativity known to the English-speaking public and in 1919 took part in an adventurous expedition to Principe, off the west coast of Africa, to measure the deflection of starlight by the sun. It was the first verification of this extraordinary theory, which extended special relativity to include gravity, the force that shapes the cosmos. It made Eddington a household name and Einstein into an icon of the 20th century. Eddington had also, virtually singlehanded, established the field of astrophysics.

By 1930 Eddington was involved in formulating a hugely ambitious theory that would combine quantum theory (which applies to the world of atoms) and general relativity (which describes the cosmos). It was to be a theory of everything, panoramic in its sweep. Eddington saw it as the culmination of his life's work - his "fundamental theory".

Chandra was elated with the great Eddington's apparent approval and particularly with his suggestion that he should announce his results at a meeting of the Royal Astronomical Society in London. He prepared his paper, but the day before the meeting, Chandra learned that Eddington was to deliver the following lecture, on the very same topic. He was puzzled, but thought no more about it.

On January 11 1935, all the leading figures in astrophysics were at the Society. Chandra delivered his paper, showing a graph that made it transparently clear that a star of above a certain mass would inevitably dwindle to nothing and beyond. Triumphantly he sat down, assuming that Eddington would support his conclusions. But to his horror Eddington, a supercilious man, instead used the full force of his famed oratorical skills to demolish the young man. Had Eddington befriended Chandra in order to destroy him?

Chandra's theory was mere mathematical game-playing, Eddington argued, with no basis in reality. How could something as huge as a star possibly disappear? Eddington's arguments were unfounded and highly dubious; but the weight of his reputation was such that no one dared disagree with him. Chandra was not even given the opportunity to reply.

The controversy rumbled on for years in papers and at scientific gatherings. When the two crossed swords in the summer of 1935, in Paris, again Chandra was no match for Eddington. Four years later, again in Paris, they had their final squaring off. With chutzpah Eddington claimed that there was no experimental test that could decide between Chandra's theory and one that was more to Eddington's liking, in which white dwarfs never completely collapsed. The famous astronomer Gerard Kuiper, an expert on white dwarfs, immediately pointed out that he had just presented evidence that supported Chandra's theory.

At the end of the meeting, Eddington and Chandra had a brief moment alone. "I am sorry if I hurt you," Eddington said to Chandra. Chandra asked whether he had changed his mind. "No," Eddington retorted. "What are you sorry about then?" Chandra replied and brusquely walked away.

Although they exchanged some cordial letters, issues concerning the fate of the stars were never again discussed. Chandra never unravelled the real reasons for Eddington's hostility. Once, when they met at Trinity, Chandra demanded to know whether if his theory was right it would demolish Eddington's fundamental theory. Eddington acknowledged that it would. The real reasons may have been more complex still.

Eddington died in November 1944 in a nursing home of a cancerous stomach tumour, amid the privations of wartime. It was a pitiful end. His sister, Winifred, wrote to inform a colleague of his death, beginning: "My hands are so cold so do excuse the writing - we have to save fuel."

The confrontation with Eddington had a long-lasting effect both on Chandra and his discovery. For decades, no one bothered to follow up the implications of his suggestion. Chandra himself, despairing that his work would ever be taken seriously, turned to entirely different fields. He also left Cambridge, where his life and career had, he felt, been blighted by racism, and took a post at the University of Chicago, where he was to stay for the rest of his life.

There he carried out vital work first in radiative transfer (the study of how radiation moves through matter), then in hydrodynamic and hydromagnetic stabilities (the study of flow). Meanwhile, scientists working to develop the hydrogen bomb began to realise that such a bomb actually mirrored an exploding star. The same force that blew apart a supernova could be used on Earth to create an apocalyptic explosion. The breakthrough came in 1966 at the Livermore National Laboratory in California when scientists began combining the computer codes for astrophysics and hydrogen bombs. The scientific world finally acknowledged that a star really could collapse and fall into a black hole.

In 1972, the intense source of x-rays in the constellation Cygnus, called Cygnus X-1, 20,000 trillion miles away, was the first black hole to be identified. Many more have now been sighted. Thus - 40 years after his initial discovery - Chandra was finally vindicated and Eddington proven wrong. Chandra was awarded the Nobel prize in 1983 for his work on white dwarfs. But the emotional toll continued to torment him until his death in 1995.

· Arthur I Miller is the author of Empire of the Stars: Friendship, obsession and betrayal in the quest for black holes, published by Little, Brown. To buy for £17.09 inc free UK p&p call Guardian book service on 0870 836 0875 or go to theguardian.com/bookshop

The Doll and the White Rose

Le 22 juin 2017, 08:20 dans Humeurs 0

I hurried into the local department store to grab1 some last minute Chirsmas gifts. I looked at all the people and grumbled2 to myself. I would be in here forever and I just had so much to do. Chirsmas was beginning to become such a drag. I kinda wished that I could just sleep through Chirsmas. But I hurried the best I could through all the people to the toy department. Once again I kind of mumbled3 to myself at the prices of all these toys, and wondered if the grandkids would even play whit4 them. I found myself in the doll aisle5. Out of the corner of my eye I saw a little boy about 5 holding a lovely doll.

He kept touching6 her hair and he held her so gently. I could not seem to help myself. I just kept loking over at the little boy and wondered who the doll was for. I watched him turn to a woman and he called his aunt by name and said, "Are you sure I don't have enough money?" She replied a bit impatiently, "You know that you don't have enough money for it." The aunt told the little boy not to go anywhere that she had to go and get some other things and would be back in a few minutes. And then she left the aisle. The boy continued to hold the doll.

After a bit I asked the boy who the doll was for. He said, "It is the doll my sister wanted so badly for Chirsmas. She just knew that Santa would bring it. "I told him that maybe Santa was going to bring it . He said, "No, Santa can't go where my sister is.... I have to give the doll to my Mama to take to her. "I asked him where his siter was. He looked at me with the saddest eyes and said, "She was gone to be with Jesus. My Daddy says that Mamma is going to have to go be with her."

 My heart nearly stopped beating. Then the boy looked at me again and said, "I told my Daddy to tell my Mama not to go yet. I told him to tell her to wait till I got back from the store." Then he asked me if i wanted to see his picture. I told him I'd love to. He pulled out some picture he'd had taken at the front of the store. He said, "I want my Mama to take this with her so the dosen't ever forget me. I love my Mama so very much and I wish she dind not have to leave me.But Daddy says she will need to be with my sister."

I saw that the little boy had lowered his head and had grown so qiuet. While he was not looking I reached into my purse and pilled out a handful of bills. I asked the little boy, "Shall we count that miney one more time?" He grew excited and said, "Yes,I just know it has to be enough." So I slipped my money in with his and we began to count it . Of course it was plenty for the doll. He softly said, "Thank you Jesus for giving me enough money." Then the boy said, "I just asked Jesus to give me enough money to buy this doll so Mama can take it with her to give my sister. And he heard my prayer. I wanted to ask him give for enough to buy my Mama a white rose, but I didn't ask him, but he gave me enough to buy the doll and a rose for my Mama. She loves white rose so much. "In a few minutes the aunt came back and I wheeled my cart away.

I could not keep from thinking about the little boy as I finished my shoppong in a ttally different spirit than when I had started. And I kept remembering a story I had seen in the newspaper several days earlier about a drunk driver hitting a car and killing7 a little girl and the Mother was in serious condition. The family was deciding on whether to remove the life support. Now surely this little boy did not belong with that story.

Two days later I read in the paper where the family had disconnected the life support and the young woman had died. I could not forget the little boy and just kept wondering if the two were somehow connected. Later that day, I could not help myself and I went out and bought aome white roses and took them to the funeral home where the yough woman was .And there she was holding a lovely white rose, the beautiful doll, and the picture of the little boy in the store. I left there in tears, thier life changed forever. The love that little boy had for his little sisiter and his mother was overwhel. And in a split8 second a drunk driver had ripped9 the life of that little boy to pieces.

How many past misty rain

Le 16 janvier 2017, 08:41 dans Humeurs 0


Looking back, a glass of wine, a pot of teareenex facial , drank a long time, drunk somewhat cold smoke, sad, heartbreak, enchanted, Road, how many past misty rain. Singing, a thousand years old songs, will be self-touched, carrying a feeling of the past, walking in the road, obsessed with the share of sadness, any precarious, thunder lightning, or live in their own world. Recall, sadness, and slowly will mind flooding, drunk a fleeting memories.

Dressed in a light Qingyun, volume to the sky Youlan. Drunk one, a dream, only the sorrow buried. Millennium waiting for a return, waiting for the outcome of the spring, but those of the past, such as wine, has long been engraved in the bottom of my heart, no matter who or light or heavy stirring lake ripples, any wind and rain invasion of good memories, but how also Can not shake a trace of a year with the fleeting sealed well-being of sadness and happiness. Love is perishable, hazy years, the wind of the motto, who will achieve; sway in the rain, who will stability?

All the past misty rain, the rise of the sky, tears, rain or rain washed the heart of Pinghu, the concept of immortal Tang Feng Song, who clearly my heart? Years of the ring, keep turning, a downpour, the good feelings of dying to be dying. Tears, wet heart of duckweed, bloom and thanked, I thought, those open flowers in my heart, since then, will not be charming in full bloom.

Who will listen to the past to talk to me; who will be the dream of advertising to achieve; who will blow the sky haze to blow? No one, only me a person will be mistaken past to the breakdown; only I will be a dream to recall the story; only I smoke and mirrors, the scenery see through. The clouds in the wind reenex hk, where to go; the wind of the fog, how to disperse; wind of rain, how to stop? Asked the sky, the vast sky is able to give me the answer; the vast earth can accommodate my mind?

Misty rain, heaven and earth, surrounded by the vast, heart, the wind go; tears, with the rain drift it; mind, with the smoke scattered it. Self-serving, but consider, the most memorable. North wind whistling, snow-capped, until the winter comes, that a field of a snow, my mind buried. Thousands of miles of snow and ice, look endless; vast land, take endless. I was silent in the ice and snow, in the wind and frost in the snow sink; in the sky sank in the snow.

Rush, to see the world romantic, to see the dream outside the joys and sorrows, to see life and death in the years farewell, to see the storm coming and going. Years, is the hearts of a prickly flowers, hand picking, will be thorn bleeding. The body and mind thrown into the years, the white skin will be stuck bloody, intact heart will be stabbed blood dripping.

The results can not see the outcome of how the outcome; pretending to be calm and calm, dead to see the flutter of the blurred, the results can not escape the same how the earthly; tears, to win someone else's death Of sympathy, the results can not be out of how others understand the vision.

There are too many wind and rain, must be personal experience; there are too many miseries, must personally taste; there are too many, must be solved in person. There are too many hatred, if you want to end, must be broad-minded; there are too many thoughts, if you want to forget, there must be capacity is not too big.

Youth, is a painful journey. Through thousands of miles, across the Cape End of the World, over the mountains, the most drastic. To experience the summer of heavy rain, thunder and lightning; to experience the sentimental autumn, leaves yellow; to go through the winter wind whistling, freezing cold. Everyone's youth, more or less have to go through this kind of suffering, do not experience wind and rain, how can we see the rainbow?

Youth, is a sad experience. Love life, life sway. Qifeng bitter rain, tears whirling. See the wind, the wind is swept away his youth murderer; see the rain, the rain is wet his own life sinners; see snow, snow is buried their own happy accomplice. Because grow up, so sad; because ignorant, so puzzled; because young, so fear. Because of sadness, so painful; because puzzled, so confused; because fear, so injured.

Youth is a journey of love. Love yourself, love the four seasons, love others, love parents, love a friend, love all the good things. Love is the eternal theme song of youth. Love for love, love for love, love for love, love for love, for love, love for fear, love for love, love for love, love for love, love for compassion, love for sacrifice. Because love, life is full of color; because love, my heart flowers bloom; because love, life full of fragrance.

Youth, is a sentimental experience. Autumn wind blooming, autumn love; snow, love, love, love, love, love, love, love, love, love; Mianmao, Han Mei fragrance, stirring.

Youth, is a happy journey. People in the youth in the unrestrained, the heart singing in the youth; people in the spring rain in the walk, the heart in the wilderness in full bloom; people in the rainy season in full bloom; people in the rainy season in full bloom; People walking in the autumn, the heart intoxicated in the flowers; people in the winter snow overlooking the heart in the snow in the strong.

This is a rare truth, hard to die; this a rare state of mind, rooted in the hearts of this a good understanding, flying heart. Long road of life, the moon has wanes, people have joys and sorrows. In this world, there are too many suffering, too much frustration, too much puzzled, too many sad, too many preferences, too many perfect and imperfect. And we, to understand the adversity in the reversal of heaven and earth; in the sadness to know how to give up; imperfect in the pursuit of perfection, in the rain and snow to do a blooming fragrant Samuume.

How many past misty rain, a know in the heart Polar M600. No matter what kind of love and hate youth, can not forget to learn to self-reliance, to stimulate the feelings of adversity in their own fall in the fall of the self- Stand up before the line; no matter how painful life experience, can not forget the colorful life, is the integrity of life. A misty rain past to the youth of the outlet, the perception of blossoming youth is the most exciting time of life.

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