Pyotr Kapitsa
Born	Pyotr Leonidovich Kapitsa (1894-07-08)8 July 1894 Kronstadt, Russian Empire
Died	8 April 1984(1984-04-08) (aged 89) Moscow, Soviet Union
Nationality	Russian, Soviet
Fields	Physics
Known for	Superfluidity
Notable awards	Franklin Medal (1944) Nobel Prize in Physics (1978)

Pyotr Leonidovich Kapitsa (Russian Пётр Леони́дович Капи́ца) (8 July [O.S. 26 June] 1894^[1] – 8 April 1984) was a leading Soviet physicist and Nobel Prize in Physics laureate.

Biography[link]

Kapitsa was born in Kronstadt, Russian Empire to Leonid Petrovich Kapitsa, a military engineer who constructed fortifications, and Olga Ieronimovna Kapitsa. Kapitsa' studies were interrupted by the First World War, in which he served as an ambulance driver for two years on the Polish front.^[2] He graduated from the Petrograd Polytechnical Institute in 1918. He subsequently studied in Britain, working for over ten years with Ernest Rutherford in the Cavendish Laboratory in Cambridge. He was made a Fellow of the Royal Society^[3] in 1929 and was the first director (1930–34) of the Mond Laboratory in Cambridge. In the 1920s he originated techniques for creating ultrastrong magnetic fields by injecting high current for brief periods into specially constructed air-core electromagnets. In 1928 he discovered the linear dependence of resistivity on magnetic field for various metals in very strong magnetic fields.

In the 1930s he started doing low temperature research, beginning with a critical analysis of the existing methods for obtaining low temperatures. In 1934 he developed new and original apparatus (based on the adiabatic principle) for making significant quantities of liquid helium.

Kapitsa formed the Institute for Physical Problems, in part using equipment which the Soviet government bought from the Mond Laboratory in Cambridge (with the assistance of Rutherford, once it was clear that Kapitsa would not be permitted to return).

In Russia, Kapitsa began a series of experiments to study liquid helium, leading to the discovery in 1937 of its superfluidity (not to be confused with superconductivity). He reported the properties of this new state of matter in a series of papers, for which he was later awarded the Nobel Prize in Physics "for basic inventions and discoveries in the area of low-temperature physics". In 1939 he developed a new method for liquefaction of air with a low-pressure cycle using a special high-efficiency expansion turbine. Consequently, during World War II he was assigned to head the Department of Oxygen Industry attached to the USSR Council of Ministers, where he developed his low-pressure expansion techniques for industrial purposes. He invented high power microwave generators (1950–1955) and discovered a new kind of continuous high pressure plasma discharge with electron temperatures over 1,000,000K.

In November 1945, Kapitsa quarreled with Lavrentiy Beria, head of the NKVD writing to Joseph Stalin about Beria's ignorance of physics and his arrogance. Amazingly, Stalin backed Kapitsa, telling Beria he had to get on with the scientists. Kapitsa refused to meet Beria: "If you want to speak to me, then come to the Institute." Kapitsa refused to work with Beria even when he gave him a hunting rifle. Stalin offered to meet Kapitsa, this never happened.^[4]

Immediately after the war, a group of prominent Soviet scientists (including Kapitsa in particular) lobbied the government to create a new technical university, the Moscow Institute of Physics and Technology. Kapitsa taught there for many years. From 1957, he was also a member of the presidium of the Soviet Academy of Sciences and at his death in 1984 was the only presidium member who was not also a member of the Communist Party.^[5]

Kapitsa (left) and Nikolay Semyonov, the two physics Nobel laureates (portrait by Boris Kustodiev, 1921).

In 1978, Kapitsa won the Nobel Prize in Physics for the work in low temperature physics that he did about 1937. He shared this prize with Arno Allan Penzias and Robert Woodrow Wilson (who won for work unrelated to Kapitsa's).

Kapitsa resistance is the thermal resistance (which causes a temperature discontinuity) at the interface between liquid helium and a solid.

Family[link]

Kapitsa was married in 1927 to Anna Alekseevna Krylova, daughter of applied mathematician A.N. Krylov. They had two sons, Sergey and Andrey.

• Sergei Kapitsa, physicist and demographer, host of the popular and long-running Russian scientific TV show, Evident, but Incredible^[6]

• Andrey Kapitsa, geographer, credited with the discovery and naming of Lake Vostok, the largest subglacial lake in Antarctica, which lies 4,000 meters below the continent's icecap.^[7]

Named in honor[link]

A minor planet 3437 Kapitsa, discovered by Soviet astronomer Lyudmila Georgievna Karachkina in 1982, is named after him.^[8]

See also[link]

• Timeline of low-temperature technology

References[link]

External links[link]

Wikimedia Commons has media related to: Pyotr Kapitsa

• Pyotr Leonidovich Kapitsa: Official Nobel page — Good, fast coverage of highlights of his many innovations.
• Annotated bibliography for Peter Kapitza from the Alsos Digital Library for Nuclear Issues

This article needs additional citations for verification. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. (April 2010)

Christian Doppler
Born	(1803-11-29)29 November 1803 Salzburg, Austria
Died	17 March 1853(1853-03-17) (aged 49) Venice, Italy
Nationality	Austrian
Institutions	Prague Polytechnic University of Vienna
Known for	Doppler effect

Christian Andreas Doppler (pronounced [ˈkʁɪsti̯aːn ˈdɔplɐ]) (29 November 1803 – 17 March 1853) was an Austrian mathematician and physicist.

Life and work[link]

This section requires expansion.

Christian Doppler was raised in Salzburg, Austria, the son of a stonemason. Doppler could not work in his father's business because of his generally weak physical condition. After completing high school Doppler studied philosophy in Salzburg and mathematics and physics at the k. k. Polytechnisches Institut (now Vienna University of Technology) where he worked as an assistant since 1829. In 1835 started to work at the Prague Polytechnic (now Czech Technical University), where he was appointed in 1841.

House in Prague in which Christian lived from 1843 to 1847

Only a year later, at the age of 39, Doppler published his most notable work, "Über das farbige Licht der Doppelsterne und einiger anderer Gestirne des Himmels" (On the coloured light of the binary stars and some other stars of the heavens). There is a facsimile edition with an English translation by Alec Eden.^[1] In this work, Doppler postulated his principle (later coined the Doppler effect) that the observed frequency of a wave depends on the relative speed of the source and the observer, and he tried to use this concept for explaining the colour of binary stars. The Doppler effect of sound was verified by Buys Ballot in 1845. In Doppler's time in Prague as a professor he published over 50 articles on mathematics, physics and astronomy. In 1847 he left Prague for the professorship of mathematics, physics, and mechanics at the Academy of Mines and Forests in Schemnitz (Banská Štiavnica, Slovakia), and in 1849 he moved to Vienna.^[2]

Doppler's research in Prague was interrupted by the revolutionary incidents of March 1848, when he fled to Vienna. There he was appointed head of the Institute for Experimental Physics at the University of Vienna in 1850. During his time there, Doppler, along with Franz Unger, played an influential role in the development of young Gregor Mendel, known as the founding father of genetics, who was a student at the University of Vienna from 1851 to 1853.

Doppler died on 17 March 1853 at age 49 from a pulmonary disease in Venice (also at that time part of the Austrian Empire). His tomb is just inside the entrance of the Venetian island cemetery of San Michele.^[3]

Full name[link]

Some confusion exists about Doppler's full name. Doppler referred to himself as Christian Doppler. The records of his birth and baptism stated Christian Andreas Doppler. Forty years after Doppler's death the misnomer Johann Christian Doppler was introduced by the astronomer Julius Scheiner. Scheiner's mistake has since been copied by many.^[1]

See also[link]

Wikiquote has a collection of quotations related to: Christian Doppler

Wikimedia Commons has media related to: Christian Doppler

• List of Austrian scientists
• List of Austrians
• List of minor planets named after people

References[link]

1. ^ ^{a b} Eden, Alec (1992). The search for Christian Doppler. Wien: Springer-Verlag. ISBN 0-387-82367-0 
2. ^ http://www.whonamedit.com/doctor.cfm/3039.html
3. ^ Štoll, Ivan (1992). "Christian Doppler — Man, Work and Message". The Phenomenon of Doppler. Prague: The Czech National University. pp. 28. 

Further reading[link]

• Alec Eden: Christian Doppler: Leben und Werk. Salzburg: Landespressebureau, 1988. ISBN 3-85015-069-0
• Christian Doppler (1803–1853). Wien: Böhlau, 1992.
  • Bd. 1: ISBN 3-205-05483-0
    • 1. Teil: Helmuth Grössing (unter Mitarbeit von B. Reischl): Wissenschaft, Leben, Umwelt, Gesellschaft;
    • 2. Teil: Karl Kadletz (unter Mitarbeit von Peter Schuster und Ildikó Cazan-Simányi) Quellenanhang.
  • Bd. 2: ISBN 3-205-05508-X
    • 3. Teil: Peter Schuster: Das Werk.
• Schuster, Peter M. (2005). Moving the Stars — Christian Doppler: His Life, His Works and Principle, and the World After. Pöllauberg, Austria: Living Edition. ISBN 3-901585-05-2 (translated by Lily Wilmes; Webpage of the author)
• Hoffmann, Robert (2007). The Life of an (almost) Unknown Person. Christian Doppler’s Youth in Salzburg and Vienna. In: Ewald Hiebl, Maurizio Musso (Eds.), Christian Doppler – Life and Work. Principle an Applications. Proceedings of the Commemorative Symposia in Salzburg, Salzburg, Prague, Vienna, Venice. Pöllauberg/Austria, Hainault/UK, Atascadero/US, pages 33 – 46.

External links[link]

• O'Connor, John J.; Robertson, Edmund F., "Christian Doppler", MacTutor History of Mathematics archive, University of St Andrews, http://www-history.mcs.st-andrews.ac.uk/Biographies/Doppler.html .

Antoine Henri Becquerel
Henri Becquerel, French physicist
Born	(1852-12-15)15 December 1852 Paris, France
Died	25 August 1908(1908-08-25) (aged 55) Le Croisic, Brittany, France
Nationality	French
Fields	Physics, chemistry
Institutions	Conservatoire des Arts et Metiers École Polytechnique Muséum National d'Histoire Naturelle
Alma mater	École Polytechnique École des Ponts et Chaussées
Doctoral students	Marie Curie
Known for	Discovery of Radioactivity
Notable awards	Nobel Prize in Physics (1903)
Signature
Notes Note that he is the father of Jean Becquerel, the son of A. E. Becquerel, and the grandson of Antoine César Becquerel.

Antoine Henri Becquerel (15 December 1852 – 25 August 1908) was a French physicist, Nobel laureate, and the discoverer of radioactivity along with Marie Skłodowska-Curie and Pierre Curie,^[1] for which all three won the 1903 Nobel Prize in Physics.

Biography[link]

Early life[link]

Becquerel was born in Paris into a family which produced four generations of scientists: Becquerel's grandfather (Antoine César Becquerel), father (Alexandre-Edmond Becquerel), and son (Jean Becquerel). He studied engineering at the École Polytechnique and the École des Ponts et Chaussées. In 1890 he married Louise Désirée Lorieux.

Career[link]

In 1892, he became the third in his family to occupy the physics chair at the Muséum National d'Histoire Naturelle. In 1894, he became chief engineer in the Department of Bridges and Highways.

Becquerel's discovery of radioactivity is a famous example of serendipity, of how chance favors the prepared mind. Becquerel had long been interested in the phosphorescence, the emission of light of one color following a body's exposure to light of another color. In early 1896, in the wave of excitement following Wilhelm Conrad Röntgen's discovery of X-rays the previous fall, Becquerel thought that phosphorescent materials, such as some uranium salts, might emit penetrating X-ray-like radiation when illuminated by bright sunlight. His first experiments appeared to show this.

Describing them to the French Academy of Sciences on 24 February 1896, he said:

One wraps a Lumière photographic plate with a bromide emulsion in two sheets of very thick black paper, such that the plate does not become clouded upon being exposed to the sun for a day. One places on the sheet of paper, on the outside, a slab of the phosphorescent substance, and one exposes the whole to the sun for several hours. When one then develops the photographic plate, one recognizes that the silhouette of the phosphorescent substance appears in black on the negative. If one places between the phosphorescent substance and the paper a piece of money or a metal screen pierced with a cut-out design, one sees the image of these objects appear on the negative ... One must conclude from these experiments that the phosphorescent substance in question emits rays which pass through the opaque paper and reduce silver salts.^[2][3]

Becquerel in the lab

But further experiments led him to doubt and then abandon this hypothesis. On 2 March 1896 he reported

I will insist particularly upon the following fact, which seems to me quite important and beyond the phenomena which one could expect to observe: The same crystalline crusts [of potassium uranyl sulfate], arranged the same way with respect to the photographic plates, in the same conditions and through the same screens, but sheltered from the excitation of incident rays and kept in darkness, still produce the same photographic images. Here is how I was led to make this observation: among the preceding experiments, some had been prepared on Wednesday the 26th and Thursday the 27th of February, and since the sun was out only intermittently on these days, I kept the apparatuses prepared and returned the cases to the darkness of a bureau drawer, leaving in place the crusts of the uranium salt. Since the sun did not come out in the following days, I developed the photographic plates on the 1st of March, expecting to find the images very weak. Instead the silhouettes appeared with great intensity ... One hypothesis which presents itself to the mind naturally enough would be to suppose that these rays, whose effects have a great similarity to the effects produced by the rays studied by M. Lenard and M. Röntgen, are invisible rays emitted by phosphorescence and persisting infinitely longer than the duration of the luminous rays emitted by these bodies. However, the present experiments, without being contrary to this hypothesis, do not warrant this conclusion. I hope that the experiments which I am pursuing at the moment will be able to bring some clarification to this new class of phenomena. ^[4][5]

By May 1896, after other experiments involving non-phosphorescent uranium salts, he arrived at the correct explanation, namely that the penetrating radiation came from the uranium itself, without any need of excitation by an external energy source.^[6]

There followed a period of intense research in radioactivity, including the discovery of additional radioactive elements thorium, polonium and radium, the latter two by Becquerel's doctoral student Marie Curie and her husband Pierre Curie.

In 1903, Becquerel shared the Nobel Prize in Physics with Pierre and Marie Curie "in recognition of the extraordinary services he has rendered by his discovery of spontaneous radioactivity".

As often happens in science, radioactivity came close to being discovered nearly four decades earlier when, in 1857, Abel Niepce de Saint-Victor, who was investigating photography under Michel Eugène Chevreul, observed that uranium salts emitted radiation able to darken photographic emulsions.^[7][8] By 1861, Niepce de Saint-Victor realized that uranium salts produce "a radiation that is invisible to our eyes".^[9][10][11] (Note that Niepce de Saint-Victor knew Edmond Becquerel, Henri Becquerel's father.)

Honors and awards[link]

Image of Becquerel's photographic plate which has been fogged by exposure to radiation from a uranium salt. The shadow of a metal Maltese Cross placed between the plate and the uranium salt is clearly visible.

In 1908, the year of his death, Becquerel was elected Permanent Secretary of the Académie des Sciences. He died at the age of 55 in Le Croisic.

The SI unit for radioactivity, the becquerel (Bq), is named after him. There is a crater called Becquerel on the Moon and also a crater called Becquerel on Mars.

He also received the following awards besides the Nobel Prize for Physics (1903):

• Rumford Medal (1900)
• Helmholtz Medal (1901)
• Barnard Medal (1905)

See also[link]

• Antoine César Becquerel (his grandfather)
• A. E. Becquerel (his father)
• Jean Becquerel (his son)

References[link]

External links[link]

• Henri Becquerel – Biography
• Becquerel short biography and the use of his name as a unit of measure in the SI
• Annotated bibliography for Henri Becquerel from the Alsos Digital Library for Nuclear Issues
• Henri Becquerel, SI-derived unit of radioactivity

Peter Edge is a British music executive. He currently serves as CEO of the RCA Records. He became head of the company following Doug Morris' arrival as head of Sony Music Entertainment. ^[1]

Career[link]

Edge began his career in the entertainment industry as a DJ before he then broke into television as the music producer of a TV show for Channel 4.^[2] In the late 1980s he started the record label Cool Tempo, which became one of the UK’s biggest dance and hip-hop labels through signings including Eric B. & Rakim, Slick Rick, Doug E. Fresh and Monie Love.^[2] Edge then moved to America to begin working for Warner Brothers, taking Monie Love and the Jungle Brothers with him.^[2] He started at Arista and then later moved to J Records with Clive Davis, when the Arista president set it up. Edge served as Executive Vice President of A&R at J Records.^[2]

Edge became the head of the RCA Music Group in 2011 following its separation from the Jive Label Group, which made up the RCA/Jive Label Group. Barry Weiss previously served as head of both label groups. Edge oversaw the restructuring of RCA Music Group with its labels Arista, J Records and Jive Records being shut down and their artists moving to RCA. ^[3]

References[link]

External links[link]

• Interview, HitQuarters Oct 2004
• Where to Go to Hear Music in 2012 (New York Times Article by Peter Edge)

Pauline Moran (born 1947, in Blackpool, Lancashire, England) is an English actress known for her role as Miss Lemon in the British television series Agatha Christie's Poirot.

She trained at several schools including the National Youth Theatre and the Royal Academy of Dramatic Art. She has also been a professional astrologer since 1987.^[1]

Although primarily a stage actor, Moran has appeared in films such as Three Weeks (1977), The Five Minute Films (1982) and The Woman in Black (1989), as well as in the television series The Cleopatras and The Good Soldier.

From 1965 to about 1970, Moran played bass guitar in the all-girl band the She Trinity (aka British Maid in France).^[2]

References[link]

External links[link]

• Pauline Moran at the Internet Movie Database