Two scholars with British connections were among the Nobel laureates announced this week.
Amartya Sen, of the University of Cambridge, has won the Nobel prize for his work on welfare economics. Speaking from New York this week, Professor Sen said: "I feel very happy personally, and I am pleased that the citation is for welfare economics - the assessment of how people are doing in a society."
Tipped to win the prize by previous laureates, Professor Sen has been described as "the conscience of the economics profession". He said: "I am obsessively concerned with poverty, starvation and famine. They are all remediable."
Professor Sen has challenged the view that famine is caused by a lack of food by showing that in some cases the food supply is no different to that in non-famine years. In other cases, famine-stricken areas have exported food.
Born in Bengal in 1933, Amartya Sen received his PhD from the University of Cambridge. The universities of Delhi, Oxford, Cornell, Princeton and Harvard can also lay claim to him, along with the London School of Economics. He returned to Cambridge earlier this year.
The British mathematician John Pople shared the Nobel prize in chemistry. Professor Pople, who is now based at Northwestern University in Illinois, developed a computer program that can predict the behaviour and properties of a single molecule.
"The program is used in all universities and industries concerned with computational chemistry, including drug development and nuclear fuels," said Nicholas Hardy, of the University of Cambridge, who has worked with Professor Pople for the past 30 years. "The computer program predicts behaviours and properties that could not be done by experiments, such as the shape of molecules and the types of bonds they form.
"John Pople has worked hard all his life and been very influential in computational chemistry," said Professor Hardy.
Professor Pople shares the chemistry prize with Walter Kohn of the University of California, Santa Barbara who was honoured for finding a short-cut for calculations in quantum chemistry.
The Nobel prize in physics was also won for work at the quantum level. Bob Laughlin, of Stanford University, Horst Stormer of Columbia University and Daniel Tsui of Princeton University discovered particles that appear to have a fractional electric charge.
Mike Gunn, of the University of Bristol, explained: "If you imagine Scottish country dancing, you can understand what is going on in the room by looking at two dancers. The way that electrons behave at the interface of two semiconductors in a high magnetic field at a low temperature is very different.
"It is as though each dancer had as many arms as the number of dancers in the room, and they are all whirling around each other. This was a very unexpected result and an extraordinary act of imagination."
American scientists Robert Furchgott, Ferid Murad and Louis Ignarro, won the Nobel prize for medicine for the discovery that nitric oxide is a signalling molecule in the cardiovascular system. The media said the prize was a reward for work that led to the development of the drug Viagra.
Portuguese writer Jose Saramago won the prize for literature.