American physicist Percy Bridgman won the Nobel Prize in physics in 1946. Bridgman studied the properties of materials under high pressure and made it possible to synthesize diamonds.
Percy Williams Bridgman (1882-1961), American physicist and Nobel laureate, who was noted for his study of the behavior of materials at high pressure. Bridgman was born in Cambridge, Massachusetts, and educated at Harvard University. He joined the physics department of Harvard in 1910 and was appointed a full professor in 1919.
In his study of high-pressure phenomena, Bridgman was often forced to develop his own experimental equipment. Eventually he was able to create pressures as high as 400,000 atmospheres. Bridgman did experiments that explored the mechanical and thermodynamic properties of materials at high pressure (see Thermodynamics). In addition to the scientific discoveries he made using his equipment, the techniques he developed enabled others to make important advances in high-pressure science and engineering, such as the ability to synthesize diamonds, which was first done in 1955. Bridgman received the 1946 Nobel Prize in physics for the development of his experimental apparatus, and for the discoveries he made using that apparatus. Bridgman is also known for his writings on the conceptual foundations of physics. Among his works in this area are The Logic of Modern Physics (1927) and The Way Things Are (1959).
American physicist Walter Houser Brattain won the Nobel Prize in physics in 1956. Brattain worked on the team that developed the transistor and the semiconductor.
Walter Houser Brattain (1902-87), American physicist and Nobel laureate, born in Xiamen (Amoy), China. After working as a physicist in the radio division of the National Institute of Standards and Technology, in 1929 he joined the staff of Bell Telephone Laboratories. While working at Bell, Brattain and the American physicists William Shockley and John Bardeen developed a small electronic device called the transistor. First announced in 1948, the transistor was perfected by 1952 for commercial use in portable radios, hearing aids, and other devices. For his work on semiconductors and discovery of the transistor effect, Brattain shared the 1956 Nobel Prize in physics with Shockley and Bardeen.
Dutch-American physicist Nicolaas Bloembergen won the Nobel Prize in physics in 1952. Bloembergen developed laser spectroscopy.
Nicolaas Bloembergen, born in 1920, Dutch-American physicist and Nobel Prize winner. Bloembergen is noted for his pioneering research in laser spectroscopy, a technique that uses energy emissions to study the properties of matter. For his work in developing laser spectroscopy, Bloembergen received the 1981 Nobel Prize in physics, which he shared with Swedish physicist Kai Manne Borje Siegbahn and American physicist Arthur Leonard Schawlow.
Bloembergen was born in Dordrecht, the Netherlands, and received his Ph.D. degree in 1948 from the Leiden University. In 1951 he joined the faculty of Harvard University in Cambridge, Massachusetts, where he spent the remainder of his career. He became a United States citizen in 1958.
Spectroscopy is the study of the electromagnetic spectrum produced by a substance when exposed to certain kinds of energy, such as radiation. The substance absorbs or emits some of the energy, thereby producing a spectrum that can be carefully measured and analyzed. The spectrum provides information about molecular-energy levels, chemical bonds, and other features of the substance.
Bloembergen was especially interested in using lasers to excite a substance, and then studying the relative amounts of energy the substance absorbs. Lasers are intense beams of light waves. However, at very high intensities, the traditional laws of optics do not apply. Bloembergen worked out new laws of optics for these situations and used these laws to develop additional techniques for laser spectroscopy. Applications for these techniques range from the analysis of biological substances to the study of combustion in jet engines.
Swiss-born American physicist Felix Bloch won the Nobel Prize in physics in 1952. Bloch won the prize for his development of high-precision methods in nuclear magnetism and for discoveries stemming from these methods.
Felix Bloch (1905-1983), Swiss-born American physicist, educator, and cowinner of the 1952 Nobel Prize for physics. Bloch shared the Nobel Prize with American physicist Edward Mills Purcell for their development of a new method for the precise measurements of the strength of the magnetic field of the atomic nucleus, called nuclear magnetic resonance (NMR). A number of important applications have come from NMR, including magnetic resonance imaging (MRI). MRI produces detailed internal images of the human body, which helps physicians diagnose disease and injuries.
Born in Switzerland, Bloch studied engineering and physics at the Federal Institute of Technology in Zürich from 1924 to 1927. He received his Ph.D. degree in physics in 1928 from the University of Leipzig, Germany. From 1928 to 1932 he served as a researcher at a number of different universities in Europe and was a professor at the University of Leipzig from 1932 to 1933. Bloch left Germany in 1933 and worked at various institutions in Holland, Denmark, and Italy. He moved to the United States in 1934 after accepting an associate professorship of physics at Stanford University. He became an American citizen in 1939, and held his position at Stanford until his retirement in 1971. During World War II (1939-1945), Bloch worked on the Manhattan Project at Los Alamos (see Nuclear Weapons), contributing to the effort to develop an atomic bomb and to improve radar technology. In 1954 and 1955 he served as the first director-general of the European Organization for Nuclear Research (CERN), the multinational laboratory for nuclear science in Geneva, Switzerland.
In 1945 Bloch lead a team that successfully used a new method to measure the strength of the magnetic field of the nucleus using radio waves and nuclear magnetic resonance (NMR) to perform the measurements. In NMR, scientists can measure how much electromagnetic radiation of a specific frequency is absorbed by an atomic nucleus that is placed in a strong magnetic field (see Magnetism). This method helps to reveal atomic and molecular structures (see Atom). At the same time, Purcell and his research group at Harvard University made similar observations.
Scientists, researchers, and the general public continue to benefit from Bloch's discoveries. NMR revolutionized the field of chemistry and has become the most important spectroscopic (see Spectroscopy) technique in chemistry and biology. Scientists use NMR instruments to determine the moisture content of food, check the quality of drugs and medicines, and probe the nature of ribonucleic acid (RNA) and deoxyribonucleic acid (DNA) (see Nucleic Acids), the building blocks of human life.
American physicist Hans Albrecht Bethe won the Nobel Prize in physics in 1967. He studied thermonuclear fusion, the process by which hydrogen is converted into helium.
Hans Albrecht Bethe (1906-2005), German-born American physicist and Nobel laureate, noted for his contributions to theories of stellar energy production and to the development of nuclear weapons.
Hans Albrecht Bethe was born in Strasbourg, Alsace-Lorraine (then a part of Germany). He was educated at the University of Frankfurt and the University of Munich, from which he received a Ph.D. degree in 1928. Bethe taught physics at various universities in Germany from 1928 to 1933 and in England from 1933 until 1935, when he began his long association with Cornell University. He became a naturalized U.S. citizen in 1941.
Beginning in 1943 Bethe worked at Los Alamos, New Mexico, on the development of the atomic bomb, an effort known as the Manhattan Project. After initial misgivings he took part in the later development of the hydrogen bomb. At the same time Bethe continued his work for the peaceful use and international control of nuclear energy. A prime advocate of the partial test-ban agreement signed by the United States, the Soviet Union, and the United Kingdom in 1963, he later became an opponent of the Strategic Defense Initiative, proposed by the United States in the 1980s.
Bethe was awarded the 1967 Nobel Prize in physics for his studies of the production of energy by the Sun and other stars, which he postulated occurs through thermonuclear fusion, a long series of nuclear reactions by which hydrogen is converted into helium. He retired from Cornell in the mid-1970s but continued to be active in his field and to work for related causes into his 90s. See also Star (astronomy); Astrophysics.
American physicist John Bardeen won the Nobel Prize in physics in 1956 and again in 1972. The first prize was awarded for Bardeen’s part in developing the transistor, an electronic device that performed many of the functions of the vacuum tube. The second prize recognized his contribution to a theory that explains superconductivity—the total disappearance of electrical resistance in some materials at low temperatures.
John Bardeen (1908-1991), American physicist and Nobel laureate, born in Madison, Wisconsin, and educated at the University of Wisconsin and Princeton University. As a research physicist (1945-1951) at the Bell Telephone Laboratories in Murray Hill, New Jersey, he was a member of the team that developed the transistor, a tiny electronic device capable of performing most of the functions of the vacuum tube. For this work, he shared the 1956 Nobel Prize in physics with two colleagues, the American physicists William Shockley and Walter H. Brattain. Meanwhile he had joined (1951) the faculty of the University of Illinois. In 1972 he shared the Nobel Prize in physics with the American physicists Leon N. Cooper and John R. Schrieffer for the development of a theory to explain superconductivity, the disappearance of electrical resistance in certain metals and alloys at temperatures near absolute zero (see Cryogenics). Bardeen thus became the first scientist to win two Nobel Prizes in the same category.
John Vincent Atanasoff (1903-1995), American physicist, born in Hamilton, New York, who has been claimed as the developer of certain basic techniques later used in the design of the first electronic digital computer, ENIAC (Electronic Numerical Integrator and Computer). While teaching at Iowa State College, Atanasoff built a simple vacuum-tube computing device that he showed to several people, including one of the later builders of ENIAC, but he did not succeed in marketing his own device. A 1971 lawsuit by an electronics firm against a rival firm holding the patent on ENIAC principles, however—on the grounds that Atanasoff's ideas had been used without being credited—led to the invalidation of that patent in 1973.
Philip W. Anderson, born in 1923, American physicist and Nobel laureate who helped develop basic theories of magnetism and conduction in solid-state physics. Anderson shared the 1977 Nobel Prize for physics with British physicist Sir Nevill Francis Mott and American physicist John Hasbrouck Van Vleck.
Anderson was born in Indianapolis, Indiana. He earned his bachelor's, master's and doctoral degrees from Harvard University, where he was a student of John Van Vleck. Anderson studied at Harvard University from 1939 to 1949, except for the years 1943 to 1945, when he interrupted his education to work as a radio engineer in the United States Navy during World War II.
After he earned his doctorate from Harvard, Anderson went to work at Bell Laboratories in New Jersey. Anderson worked for Bell Laboratories until his retirement in 1984, while serving terms as professor of physics at several universities, including the University of Tokyo and Princeton University. From 1967 to 1975 Anderson was a visiting professor of theoretical physics at the University of Cambridge in England, where he worked with Nevill Mott.
Anderson's work focused on solid-state physics, also known as condensed-matter physics. One of the major advances of solid-state physics was the discovery of semiconductors in the 1920s. A semiconductor is a material that conducts electricity at room temperature more readily than an insulator, but less easily than a metal. Use of semiconductors made possible the development of integrated circuits, the components that control many electronic devices such as computers. One of the most important semiconductors is the crystalline form of silicon. Anderson's work concentrated on solids with no crystalline structure, which are called amorphous materials.
Anderson's work with amorphous materials like amorphous silicon led him to demonstrate in 1958 that it is possible for an electron to get trapped in a small area. This phenomenon, known as “Anderson localization,” suggests that amorphous materials can be used in place of the crystalline semiconductors used today. Anderson's discoveries also led to the development of electronic switching and memory devices made from amorphous materials such as glass. The field of amorphous semiconductors has become an area of intense research since Anderson's work.
American physicist Carl David Anderson won the Nobel Prize in physics in 1936. Anderson discovered the positron, a fundamental subatomic particle.
Carl David Anderson (1905-91), American physicist and Nobel laureate. Anderson was born in New York City and educated at the California Institute of Technology, where he attained full professorial rank in 1939. In 1932 he discovered the positron, or positive electron, one of the fundamental subatomic particles. For this achievement he was awarded, with Victor Franz Hess, the 1936 Nobel Prize in physics. In 1936 Anderson also confirmed experimentally the existence of the elementary nuclear particle called the meson, which had been predicted in 1935 by the Japanese physicist Yukawa Hideki.
Alexei Abrikosov, born in 1928, Russian-born American physicist and cowinner of the 2003 Nobel Prize in physics for theories that explained the properties of superconductors—metals and other substances that carry an electric current without any resistance when cooled to extremely low temperatures. Abrikosov’s insights during the 1950s helped propel an area of research that became very active in the 1980s and 1990s, as scientists developed new superconducting compounds. Superconductors are expected to find wide application in the future—for example, in new kinds of electric motors and generators, and in improved means for transmitting electric current long distances over power lines.
Abrikosov was born in Moscow in what was then the Union of Soviet Socialist Republics (USSR). He earned his doctoral degree in 1951 from the Institute for Physical Problems in Moscow, and another advanced degree, in quantum electrodynamics, from the same institution in 1955. After working at several institutions and universities in Russia, Abrikosov moved to the United States at the end of the Cold War in 1991, joining the staff at the Argonne National Laboratory outside Chicago, Illinois.
Research early in the 1900s had proved the existence of superconductivity in metals and other compounds that were cooled to near absolute zero, the lowest temperature possible: -273.15°C (-459.67°F). What was still lacking when Abrikosov began his research in the 1950s was a theoretical framework to explain how different superconducting systems worked, particularly in relation to magnetic fields. Two other Russian physicists, Vitaly L. Ginzburg and Lev Landau, explained the manner in which superconductors known at that time blocked or displaced magnetic fields. These superconductors were dubbed Type I. The theories of Ginzburg and Landau suggested another type of superconductor. Building on the Ginzburg-Landau theory, Abrikosov explained the phenomenon in which some superconductors admit a magnetic field and function in its presence under certain conditions. These superconductors were designated Type II.
Abrikosov’s theories accurately predicted the properties of Type II superconductors. These properties were subsequently discovered in new Type II superconducting compounds, including ceramic compounds that become superconducting at higher temperatures, which are more practical to achieve. Abrikosov’s theories on electricity and magnetic fields have also been applied in the development of magnetic resonance imaging (MRI) machines that can peer inside the human body, and in the high-energy accelerators that allow physicists to investigate fundamental subatomic particles, such as quarks.
In addition to the Nobel Prize, Abrikosov’s other distinctions include election to the Russian Academy of Sciences and the American Academy of Arts and Sciences. His Nobel Prize was shared with Ginzburg and with British-born American physicist Anthony J. Leggett, who was honored for separate work on the phenomenon of superfluidity.
Brian D. Josephson, born in 1940, Welsh physicist and one of the youngest recipients of a Nobel Prize. Josephson shared the 1973 Nobel for physics with Japanese physicist Leo Esaki and Norwegian-born American physicist Ivar Giaever for their research on tunneling effects in semiconductors and superconductors (see Superconductivity). According to classical physics, an electric current—and specifically, electrons—cannot flow in a circuit that is interrupted by an insulating barrier. Since the 1930s, many physicists had predicted that electrons might be able to “tunnel” through an insulating barrier if it was thin enough. Esaki, who first demonstrated tunneling in semiconductors, laid the groundwork for Giaever's research on superconducting tunnel junctions. Based on their discoveries, Josephson formulated theories predicting how electrons flow through a tunnel barrier.
Josephson was born in Cardiff, Wales. He attended Trinity College at the University of Cambridge, where he earned a B.A. (1960), an M.A. (1964), and a Ph.D. (1964) in physics. In 1962 he made his Nobel-prize winning observations about the behavior of an electrical contact between a superconducting material and a normal metal separated by a very thin insulating layer. Traditional quantum theory stated that only a small amount of current (electrons) could tunnel through the nonconducting barrier. Josephson predicted that a much higher number of electrons would actually move across the insulator. He also noted that this current would be affected by an external magnetic field. The flow of electric current through nonconductive material became known as the Josephson effect. Josephson's discoveries have had practical applications in the development of miniature electronics.
In 1964 Josephson took a teaching position at the University of Cambridge. He spent a year at the University of Illinois as a visiting research professor, returning to the University of Cambridge in 1967 to serve as assistant director of research in physics. He then worked as reader in physics for two years. In 1974 Josephson became professor of physics.
He shifted his research focus from physics to the scientific study of the mind after attending a 1971 lecture on transcendental meditation. He became interested in synthesizing modern physics and mathematics with the study of intelligence, language, higher states of consciousness, and the paranormal. With Indian chemical engineer V.S. Ramachandran, Josephson edited Consciousness and the Physical World (1979).
Egyptian American chemist Ahmed Zewail won the 1999 Nobel Prize in chemistry for his work in studying chemical reactions. Zewail
Ahmed H. Zewail, born in 1946, Egyptian American chemist and Nobel Prize winner. Zewail received the 1999 Nobel Prize in chemistry for developing a way to study chemical reactions in slow motion using ultra-short laser flashes. The Royal Swedish Academy of Sciences, which awards the Nobel Prize, said that his contributions have revolutionized chemistry, because this method of investigation enables chemists to understand and predict the nature of chemical reactions.
Zewail was born in Alexandria, Egypt. He received his bachelor's and master's degrees from the University of Alexandria. He moved to the United States and, in 1974, earned his Ph.D. degree from the University of Pennsylvania in Philadelphia. After completing his Ph.D., he went to the University of California at Berkeley as a research fellow. In 1976 Zewail joined the faculty at the California Institute of Technology (Caltech) in Pasadena, and in 1982 he became a full professor. In 1990 he became the first person to hold the Linus Pauling Chair of Chemical Physics at Caltech.
In a series of experiments he performed during the 1980s, Zewail developed what many have described as the world's fastest camera. This device uses flashes of laser light of such short duration that they “freeze” the moment when atoms and molecules come together to form new compounds. Using his laser technique, Zewail was the first person to find out how long it takes for atoms and molecules to form and to break chemical bonds. Using this ability, he has studied a variety of chemical processes, ranging from reactions in Earth’s atmosphere to biological reactions between genetic components within hemoglobin (a compound in red blood cells).
Zewail’s technique uses flashes of laser light that last for a few femtoseconds. One femtosecond equals one millionth of one billionth of a second (0.000000000000001 second). Femtochemisty is the area of physical chemistry that addresses the short time period in which chemical reactions take place and investigates why some reactions occur but not others. Zewail’s picture-taking technique made possible these investigations. One of the first major discoveries of femtochemistry was that intermediate products that form during chemical reactions differ from the starting and end products. By understanding these molecular dynamics, chemists one day may be able to better control chemical reactions and create new molecules.
Zewail has received numerous awards in addition to the Nobel Prize. In 1998 the government of Egypt issued a postage stamp bearing his portrait.
American scientist Luis Walter Alvarez won the 1968 Nobel Prize in physics. Alvarez developed the liquid hydrogen bubble-chamber, which he used to find atomic particles.
Luis Alvarez (1911-1988), American scientist. Luis Walter Alvarez was born in San Francisco and educated at the University of Chicago. He won the 1968 Nobel Prize in physics for developing the liquid hydrogen bubble-chamber, with which he found atomic particles produced by high-energy nuclear events. He also developed the proton linear accelerator known as LINEAC. Alvarez had wide-ranging interests in science. In 1981 he and his son Walter, after studying geological strata, published a controversial theory that a giant meteorite striking the earth had caused the extinction of the dinosaurs (see Dinosaur; Evolution).
American physicist William Philips shared the 1997 Nobel Prize in physics with two other reasearchers. Philips was recognized for his work on ways to cool and trap atoms.
William D. Philips, born in 1948, American physicist and Nobel laureate. Philips’s advancements in the use of special beams of light called lasers to slow, cool, and capture atoms (tiny particles that make up matter) were instrumental in furthering the study and use of atoms. In the late 1980s Philips used laser cooling to cool and slow atoms to a point not thought possible at the time. He shared the 1997 Nobel Prize for physics with two other scientists who made separate but complementary advancements, Steven Chu of the United States and Claude Cohen-Tannoudji of France. Their achievements led to a breakthrough in the study and manipulation of atoms, which in turn brought improvements to many applications, including global navigation and gravitational measurement techniques.
Philips was born in Wilkes-Barre, Pennsylvania. He earned a B.S. degree in physics at Juniata College in Huntingdon, Pennsylvania, in 1970. In 1976 he earned his Ph.D. degree in physics from Massachusetts Institute of Technology (MIT). After post-doctoral research at MIT, in 1978 he joined the National Institute of Standards and Technology (NIST), then known as the National Bureau of Standards.
Hired to work with precision electrical measurements, Philips soon also began conducting experiments in trapping atoms. He made advancements using a magnetic device to slow atoms. Meanwhile Steven Chu and a team at Bell Laboratories in Holmdel, New Jersey, began furthering the use of lasers to capture atoms. In 1985 Chu successfully used lasers in a vacuum chamber to cool atoms to 240 millionths of a Celsius degree (430 millionths of a Fahrenheit degree) above absolute zero, the point at which all matter stops moving (–273.15° C, or -459.67° F).
Philips adopted Chu’s techniques, and by 1988 Philips and his research team had cooled atoms to 40 millionths of a Celsius degree (70 millionths of a Fahrenheit degree) above absolute zero, lower than scientists thought was theoretically possible at the time. Philips came up with methods to capture atoms at regular intervals in what was termed an optical lattice.
At room temperature, atoms move at speeds of about 4000 km/h (2500 mph), much too fast for scientists to study them. The rate at which atoms move is related to the temperature of the matter made up by the atoms. Lowering the temperature of the sample of atoms slows the atoms’ motion, and vice versa. Chu and Philips developed techniques in which atoms are bombarded with finely tuned laser beams. The lasers immerse the atoms in packets of light wave energy called photons. The photons strike the atoms in a way that is roughly like raindrops hitting a beach ball. The photons have no mass, but because they travel at the speed of light, they carry enough momentum to hit the atoms and slow them down. By 1995 Claude Cohen-Tannoudji and his team used similar techniques to lower the temperature of a sample of atoms to 0.2 millionths of a Celsius degree (0.4 millionths of a Fahrenheit degree) above absolute zero.
The ability to manipulate atoms and study them more closely led to many immediate and many potential applications. Trapped atoms have increased the accuracy of atomic clocks, which increases the accuracy of other instruments that use atomic clocks, such as navigation systems. Control of atoms also helps calibrate instruments used to measure the force of gravity at spots on the earth. These measurements indicate different densities within the earth, which can reveal features such as petroleum deposits beneath the earth’s surface. The ability to manipulate atoms also raises the possibility of using atoms to etch electronic circuits, thereby increasing the circuits’ capabilities by increasing the number of circuits that can fit in a certain area.
In the 1990s Philips continued his research into ultra-cold trapped atoms. In 1995 he was elected to the American Academy of Arts and Sciences and became an NIST Fellow. Two years later he was named to the National Academy of Sciences.
Pakistani physicist Abdus Salam won the 1979 Nobel Prize in physics. He won the award for his work in developing a unification hypothesis concerning electromagnetic and weak interactions between atomic particles.
Abdus Salam (1926-1996), Pakistani physicist and Nobel laureate, known for his contributions to the understanding of the interactions of elementary particles. Salam was born in Jhang Sadar, India (now in Pakistan), attended the Government College at Lahore, and received a doctorate in mathematics and physics from the University of Cambridge in 1952. He taught at both institutions before becoming professor of theoretical physics at Imperial College, London, in 1957, and he was made director of the International Centre for Theoretical Physics in Trieste, Italy, when it was established in 1964. In 1967, with the American physicist Steven Weinberg, Salam offered a so-called unification hypothesis that incorporated the known facts about the electromagnetic and weak interactions between atomic particles (Elementary Particles). When tested, the hypothesis held up, unlike a number of alternative hypotheses. The men shared the 1979 Nobel Prize in physics for this work with American physicist Sheldon Lee Glashow, who also contributed to the understanding of particle interactions.
Askar Akayev was elected president of Kyrgyzstan in the country’s first presidential elections in 1991. He won a third term in 2000, but mass protests in 2005 forced him to flee the country and resign.
Askar A. Akayev, born in 1944, president of Kyrgyzstan from 1991 to 2005. Askar Akayevich Akayev was born in the town of Kyzyl-Bayrak in Kyrgyzstan, which was then the Kirgiz Soviet Socialist Republic (SSR) within the Union of Soviet Socialist Republics (USSR). He was educated as a physicist and spent 20 years in Leningrad (now Saint Petersburg, Russia), where he graduated with honors from the Institute of Precision Engineering and Optics. Akayev joined the Communist Party in 1981, and in 1984 he became a corresponding member of the USSR Academy of Sciences. He was selected to the vice presidency of the Kirgiz SSR Academy of Sciences in 1987, and he became the academy’s president in 1989. In 1991 he became a member of the USSR Supreme Soviet Committee on Economic Reform.
During a wave of liberalizing political reforms initiated by the leader of the USSR, Mikhail Gorbachev, Akayev was indirectly elected to the Kirgiz SSR’s newly created post of president in 1990. The republic’s parliament elected him largely because he was a liberal academic who had worked only briefly in the Communist Party apparatus. When Communist hardliners attempted a coup against Gorbachev in August 1991, Akayev was the first leader of a Soviet republic to denounce their plot. He also severed his ties to the Communist Party. After the failed coup attempt, Kyrgyzstan and other Soviet republics began to declare their independence. In October the people of Kyrgyzstan elected Akayev as president in the country’s first direct presidential elections. The USSR officially ceased to exist in December, and Kyrgyzstan joined most of the former Soviet republics in forming a loose alliance called the Commonwealth of Independent States (CIS).
Akayev immediately began to promote market-oriented reforms to restructure Kyrgyzstan’s Soviet-developed economy. Through his influence, in 1993 Kyrgyzstan became the first former Soviet republic in Central Asia to introduce its own currency, the som. Akayev also worked to establish diplomatic and economic ties with countries outside the former USSR, including the United States and other Western nations. In addition, Akayev joined Kyrgyzstan in economic and security alliances with other members of the CIS, as well as China. Akayev’s commitment to rapid economic reform helped Kyrgyzstan secure international financial assistance, including funds for infrastructure development projects.
Akayev also advocated democratic reforms, in contrast to the leaders of the other newly independent nations in Central Asia. As opposition parties and a free press became established, however, Akayev faced public criticism of his policies, as well as political opposition within the parliament. Kyrgyzstan’s new constitution, adopted in 1993, created a parliamentary system of government that transferred the functions of the head of government from the president to the prime minister. However, voters strongly endorsed Akayev and his economic programs in a 1994 referendum, strengthening his political position.
Akayev was reelected president in December 1995. Emboldened by his victory, he called for a referendum in February 1996 on constitutional amendments to enhance the powers of the president at the expense of the parliament. He claimed the changes were necessary to permit further economic restructuring in Kyrgyzstan. The referendum passed by an overwhelming majority.
In the following years, Akayev’s commitment to democratic reform was called into question. He appeared to become less tolerant of political opposition. Politicians and newspapers critical of his policies were subject to imprisonment or closure. Akayev remained committed to economic reform, but he was widely blamed for increasing poverty and lack of adequate social services.
Despite the constitutional limit of two presidential terms, the Constitutional Court of Kyrgyzstan ruled in 1998 that Akayev’s first term, which began under the old constitution, should not be counted. In 2000 Akayev was reelected with 74.5 percent of the vote in an election marred by voting irregularities. In February 2005 protests erupted in the country after some opposition candidates were disqualified from running in legislative elections. In March protestors stormed government buildings in Bishkek, and Akayev fled the country. He formally resigned in early April.
Ernest T. S. Walton Irish physicist Ernest T. S. Walton won the 1951 Nobel Prize in physics. He invented the particle accelerator and was the first to split atoms and to successfully
Ernest T. S. Walton (1903-1995), Irish physicist and Nobel Prize winner. Walton advanced the field of nuclear physics significantly, as the first scientist to create a particle accelerator (a device to smash atoms or subatomic particles together at high speeds), the first to split atoms, and the first to transform one element into another. He and British physicist Sir John Douglas Cockcroft won the 1951 Nobel Prize in physics for their atomic research with particle accelerators.
Born in Dungarvan, Ireland, Walton received a B.S. degree in physics and mathematics from Trinity College (the University of Dublin) in 1926, and an M.S. degree in physics from Trinity in 1927. He earned his Ph.D. degree from the University of Cambridge in England in 1930. Walton began his professional career in 1927 at Cambridge's Cavendish Laboratory, as research assistant to British physicist Sir Ernest Rutherford. Walton held this position until 1934, when he accepted a professorship at Trinity College, where he remained until his retirement in 1974.
While working for Rutherford at Cambridge, Walton embarked on research that would bring him wide recognition. He built a linear particle accelerator that was to prove a prototype for subsequent particle accelerators. In 1932, in collaboration with Cockcroft, Walton used this device to bombard lithium atoms, generating enough force to transform each lithium nucleus into two helium nuclei. This marked the first time that human means proved successful in the transmutation of elements (changing one element into another). Walton later succeeded in accelerating protons to such a high velocity that they were able to penetrate atomic nuclei of light elements and start nuclear reactions. He was especially interested in the relations created during this process between the energies of the protons before they hit the nuclei and those of the created nuclear particles. These experiments demonstrated that atomic nuclei contain enormous energies. The research also provided the first experimental confirmation of equations for the equivalence of mass and energy by American physicist Albert Einstein.
Walton's discoveries have had a great influence on the field of nuclear physics in the latter half of the 20th century. Physicists in laboratories in many countries continue to use his methods for accelerating charged particles to produce nuclear reactions.
Sir Chandrasekhara Venkata Raman Indian physicist Sir Chandrasekhara Venkata Raman won the 1930 Nobel Prize in physics. He discovered that monochromatic light scatters into different frequencies when
Chandrasekhara Venkata Raman (1888-1970), Indian physicist best known for his research on the molecular scattering of light. For his discovery of this effect, known as the Raman effect, he was awarded the 1930 Nobel Prize in physics.
Raman was born in Trichinopoly (now Tiruchirapalli) and educated at Presidency College in Madras (now Chennai). He was professor of physics at the University of Calcutta (now Kolkata) from 1917 to 1933 and in the latter year was appointed head of the department of physics of the Indian Institute of Science in Bangalore. In 1947 he became director of the Raman Research Institute, also in Bangalore. He was knighted in 1929 and was named president of the Indian Academy of Sciences in 1934. Raman also studied the physical nature of musical sounds and the mechanics of musical instruments. He wrote Molecular Diffraction of Light (1922) and The New Physics; Talks on Aspects of Science (1951).
Stanislau Stanislavavich Shushkevich, born in 1934, Belarusian professor and politician, who served as chairperson of the Belarusian Supreme Soviet from 1991 to 1994. Born in Minsk, the capital of Belarus, Shushkevich attended Belarus State University, where he graduated with a degree in physics in 1956. In 1969 he was appointed to the university’s faculty. In 1986 he was appointed pro-rector (vice-chancellor) of the university, a post he held until 1990. He became involved in politics in 1986 as a critic of government negligence in reporting and controlling the nuclear accident near Chernobyl’ in neighboring Ukraine. With the backing of the political organization Belarusian Popular Front, Shushkevich became a member of the Belarusian Supreme Soviet in 1990. In 1991 he became its chairperson, the republic’s top political post, and replaced Mikalay Dementey (1990-1991), who was dismissed for his failure to condemn the Communist hard-liner attempt to end the liberalizing reforms of USSR president Mikhail Gorbachev (1988-1991).
As the top Belarusian political leader, Shushkevich followed a centrist course regarding the country’s relationship with other former Soviet republics. He was one of the three original founders of the Commonwealth of Independent States (CIS), a loose alliance of former Soviet republics, and he hosted the first CIS summit. Shushkevich tried to limit the degree of integration between Belarus and the other CIS members. His stance evoked political opposition from several prominent Belarusian officials, including Prime Minister Vyacheslau Kebich (1990-1994). In April 1993 the Belarusian parliament overrode Shushkevich’s objections and voted to join the CIS collective security agreement. Shushkevich had advocated complete neutrality in military matters, and he claimed that supporters of the CIS agreement were trading independence for Russian oil. Shushkevich was ousted from his post on trumped-up charges by a Communist-dominated parliament in January 1994, largely because of his liberal political and economic views.
One of the architects of the atomic bomb, Australian physicist Mark Oliphant did research on the artificial disintegration of the atomic nucleus. After retiring from his career as a professor of physics in 1966, Oliphant served as governor of South Australia from 1971 to 1976.
Sir Mark Laurence Oliphant (1901-2000), Australian physicist and governor of South Australia. Born on October 8, 1901, Oliphant graduated from Adelaide University and in 1927 won a scholarship to the University of Cambridge, where he worked on the artificial disintegration of the atomic nucleus. A Fellow of the Royal Society by 1935, he was appointed Professor of Physics at Birmingham University in 1937, a post he held until 1950.
Returning to Australia, Oliphant became director of postgraduate research in the physical sciences at the Australian National University from 1950 to 1963 and foundation president of the Australian Academy of Science. Appointed Professor of Physics of Ionized Gases
Yukawa was born in Tokyo and was educated at the universities of Kyoto and Osaka. He became a lecturer in physics at Kyoto University in 1932 and was made professor in 1939. Yukawa also taught (1933-36) at Osaka University and was assistant professor there until 1939. He was visiting professor at the Institute for Advanced Studies at Princeton, New Jersey, in 1948 and at Columbia University from 1949 to 1953. Yukawa became (1950) professor emeritus at Osaka University and was named (1953) director of the Research Institute for Fundamental Physics at Kyoto University. Yukawa did extensive research in quantum mechanics (see Quantum Theory) and the fields of force affecting elementary nuclear particles. In 1935 he theoretically deduced the existence of the meson (see Elementary Particles), for which he was awarded the 1949 Nobel Prize in physics.
Galileo (1564-1642), Italian physicist and astronomer who, with German astronomer Johannes Kepler, initiated the scientific revolution that flowered in the work of English physicist Sir Isaac Newton. Galileo’s main contributions were, in astronomy, the use of the telescope in observation and the discovery of sunspots, mountains and valleys on the Moon, the four largest satellites of Jupiter, and the phases of Venus. In physics, he discovered the laws of falling bodies and the motions of projectiles. In the history of culture, Galileo stands as a symbol of the battle against authority for freedom of inquiry.
ARISTOTELIAN PHYSICS OF GALILEO’S TIME
Aristotelians made a sharp division between Earth and the heavens. In the heavens there could be no change except the recurring patterns produced by the circular motions of the perfectly spherical heavenly bodies. The sublunar world (the universe below the Moon) was the region of the four elements—earth, water, air, and fire—and was subject to its own distinct laws of natural motion. Fire, for instance, had lightness, which made it rise vertically, away from the center of Earth. Earthy objects fell naturally downward toward the center of Earth: the heavier the object, the faster its fall. “Natural” motions of the elements took them to their natural place, where they rested. Rest was the natural state of an element; it was motion that needed explaining, since every motion must have a cause. This common-sense physics held sway until Galileo began to undermine it.
In 1656 Newton’s mother, on the death of her second husband, returned to Woolsthorpe and took her son out of school in the hope of making him a farmer. Newton showed no talent for farming, however, and according to legend he once was found under a hedge deep in study when he should have been in the market at Grantham. Fortunately, Newton’s former teacher at Grantham recognized the boy’s intellectual gifts and eventually persuaded Newton’s mother to allow him to prepare for entrance to University of Cambridge. In June 1661 Trinity College at Cambridge admitted Newton as a subsizar (a student required to perform various domestic services). His studies included arithmetic, geometry, trigonometry, and, later, astronomy and optics. He probably received much inspiration at Trinity from distinguished mathematician and theologian Isaac Barrow, who was a professor of mathematics at the college. Barrow recognized Newton’s genius and did all he could to cultivate it. Newton earned his bachelor’s degree in January 1665.
