The Nobel Prize in Physics for 2000 has been awarded "to scientists and inventors whose work has laid the foundation of modern information tech-nology".
Half of the SEK 9 million (£630,000) prize money will be shared by Zhores I. Alferov, 70, director of the A. F. Ioffe Physico-Technical Institute in St Petersburg, Russia, and Herbert Kroemer, 72, professor of physics at the University of California, Santa Barbara, United States, who have invented and developed fast opto and microelectronic components based on layered semiconductor structures.
This technology is used in communications satellites, mobile telephone base stations, the internet's fibre-optic cables, bar-code readers and CD players.
The other half of the prize goes to Jack S. Kilby, 77, former professor at Texas A&M University, United States, who invented the microchip. Through this invention, microelectronics has become the basis of all modern technology used in computers controlling, for example, washing machines, cars, space probes and mini-calculators.
The Nobel Prize in Physiology or Medicine for 2000 has been awarded jointly to three men who have made pioneering discoveries concerning one type of signal transduction between nerve cells in the brain.
These discoveries have been crucial for an understanding of the normal function of the brain and the cause of neurological and psychiatric diseases and have lead to the development of new drugs.
The prize money is shared equally between: Arvid Carlsson, 77, emeritus professor of pharmacology, University of Gothenburg, Sweden, who discovered that dopamine is a transmitter in the brain and has great importance for our ability to control movements. His discovery has helped in the treatment of Parkinson's disease and schizophrenia; Paul Greengard, 74, professor and head of the laboratory of molecular and cellular neuroscience, the Rockefeller University, New York, United States, who discovered how dopamine and other transmitters affect the nervous system; and Eric Kandel, 70, professor at Columbia University, New York, United States, for his discoveries about how synaptic function in the brain affects learning and memory.
The Nobel Prize in Chemistry for 2000 has been awarded "for the discovery and development of conductive polymers".
It goes jointly to Alan J. Heeger, 64, professor of physics and director of the Institute for Polymers and Organic Solids at the University of California, Santa Barbara, US; Alan G. MacDiarmid, 73, professor of chemistry at the University of Pennsylvania; and Hideki Shirakawa, 64, professor of chemistry at the Institute of Materials Science, University of Tsukuba, Japan.
In the 1970s, the three men discovered that plastic can, after certain modifications, be made electrically conductive and have developed the research since. Conductive plastics are used in photographic film, shields for computer screens and displays in mobile telephones and mini-format television screens.
The Nobel Prize in Economic Sciences for 2000 has been awarded to two economists who have developed theory and methods in microeconometrics that are used in statistical analysis of individual and household behaviour.
James Heckman, 56, the Henry Schultz distinguished service professor of economics at the University of Chicago, US, receives half of the prize for his development of the theory and methods for analysing selective samples.
The other half goes to Daniel McFadden, 63, who holds the E. Morris Cox chair in economics at the University of California, Berkeley, US, for his development of theory and methods for analysing discrete choice.