Bose-Einstein statistics One of two possible ways (the other is Fermi- Dirac statistics) in which a collection of indistinguishable particles may occupy a set of available discrete energy states. The gathering of particles in the same state, which is characteristic of particles that obey Bose- Einstein statistics, accounts for the cohesive streaming of laser light and the frictionless creeping of superfluid helium (see superfluidity). The theory of this behaviour was developed in 1924-25 by Satyendra Nath Bose (1894-1974) and Albert Einstein. Bose-Einstein statistics apply only to those particles, called bosons, which have integer values of spin and so do not obey the Pauli exclusion principle.
Bosna Vbos-na\ River River, Bosnia and Herzegovina. Rising at the foot of Mount Igman, it flows northward 168 mi (271 km) before enter¬ ing the Sava River. Major cities along the Bosna include Zenica and Doboj.
Bosnia and Herzegovina \ , baz-ne-o... 1 her-ts3-go- , ve-no\ Country, Balkan Peninsula, southeastern Europe. It is bounded by Serbia and Mon¬ tenegro and by Croatia. Area: 19,772 sq mi (51,209 sq km). Population (2005 est.): 3,853,000. Capitaclass="underline" Sarajevo. Major ethnic groups include Bosniacs (Bosnian Muslims; about two-fifths of the population), Serbs
(about one-third), and Croats (about one- fifth). Languages: Bosnian, Serbian, j= ■ 1 ■ " |0 - ( ’ ° mi Croatian (all official). Religions: Christian-
ity (mostly Eastern Orthodox; also Roman
Catholic), Islam. Currency: marka. The country’s relief is largely mountainous, and elevations of more than 6,000 ft (1,800 m) are common. The land, drained by the Sava, Drina, and Neretva rivers and their tributaries, drops abruptly southward toward the Adriatic Sea. Agriculture is a mainstay of the economy; though the area possesses a variety of minerals, it remains one of the poorest regions of the former Yugoslavia. Bosnia and Herzegovina is a republic with two legislative houses; its chief of state is the chairman of the tripartite presi¬ dency, and the head of government is the chairman of the Council of Ministers. Habitation long predates the era of Roman rule, during which much of the country was included in the province of Dalmatia. Slav settle¬ ment began in the 6th century ad. For the next several centuries, parts of the region fell under the rule of Serbs, Croats, Hungarians, Venetians, and Byzantines. The Ottoman Turks invaded Bosnia in the 14th century, and after many battles it became a Turkish province in 1463. Herzegovina, then known as Hum, was taken in 1482. In the 16th and 17th centuries the area was an important Turkish outpost, constantly at war with the Habsburgs and Venice. During this period much of the population converted to Islam. At the Congress of Berlin after the Russo-Turkish War of 1877- 78, Bosnia and Herzegovina were assigned to Austria-Hungary, and they were annexed in 1908. Growing Serbian nationalism resulted in the 1914 assassination of the Austrian archduke Francis Ferdinand at Sarajevo by a Bosnian Serb, an event that precipitated World War I. After the war the area became part of the Kingdom of Serbs, Croats, and Slovenes. Fol¬ lowing World War II, the twin territories became a republic of commu¬ nist Yugoslavia. With the collapse of communist regimes in eastern Europe, Bosnia and Herzegovina declared its independence in 1992; its Serbian population objected, and conflict ensued among Serbs, Croats, and Muslims (see Bosnian conflict). A peace accord in 1995 established a loosely federated government roughly divided between the Muslim- Croat Federation of Bosnia and Herzegovina and the Serb Republic. In 1996 a NATO peacekeeping force was installed there.
Bosnian conflict (1992-98) Ethnically rooted war in Bosnia and Herze¬ govina, a republic of Yugoslavia with a multiethnic population—44% Bosniac (formerly known as Muslim), 33% Serb, and 17% Croat. Unrest began with Yugoslavia’s breakup in 1990; after a 1992 referendum, the European Community (now European Union) recognized Bosnia’s inde¬ pendence. Bosnia’s Serbs responded violently, seized 70% of Bosnian territory, besieged Sarajevo, and terrorized Bosniacs and Croats in what came to be known as “ethnic cleansing.” After bitter fighting between the Bosnian Croats and the Bosnian government, international pressure forced
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Bosnian crisis ► Boswell I 255
the two factions to sign a cease-fire and an agreement for a federation. Both then concentrated on their common enemy, the Serbs. After rejected peace plans and continued warring, Western nations, with NATO back¬ ing, imposed a final cease-fire negotiated at Dayton, Ohio, in 1995. Bos¬ nia and Herzegovina became a single state composed of two distinct entities. Today Bosnia and Herzegovina has three de facto monoethnic entities, three separate armies and police forces, and a very weak national government. See also Radovan Karadzic, Franjo Tudjman.
Bosnian crisis (1908) International crisis caused by Austria-Hungary’s annexation of the Balkan provinces of Bosnia and Herzegovina. Russia supported Serbia, which protested the annexation and demanded that Aus¬ tria cede part of the territory to Serbia, but Austria-Hungary, supported by Germany, threatened to invade Serbia if it persisted in its demands. Since Russia could not risk war against both Germany and Austria-Hungary, it was forced to accept the annexation. Though the crisis was resolved with¬ out immediate warfare, it contributed to the outbreak of World War I.
boson \'bo-,zan\ Subatomic particle with integral spin that is governed by Bose-Einstein statistics. Bosons include mesons, nuclei of even mass num¬ ber, and the particles required to embody the fields of quantum field theory. Unlike fermions, there is no limit to the number of bosons that can occupy the same quantum state, a behaviour that gives rise to the superfluidity of helium-4.
Bosporus Vbas-po-rosX Turkish Karadeniz Bogazi
X.ka-ra-de-'nez-.bo-a-'ziX Strait separating European Turkey from Asian Turkey. Connecting the Sea of Marmara with the Black Sea, it is 19 mi (31 km) long and 2.8 mi (4.4 km) at its widest. Bosporus literally means “ox ford”; it is traditionally connected with the legendary figure of Io, who in the form of a heifer crossed the Thracian Bosporus in her wan¬ derings. Because of its strategic importance for the defense of Constan¬ tinople (modern Istanbul), which straddled its southern end, the Byzantine emperors and later the Ottoman sultans constructed fortifications along its shores. With the growing influence of the European powers in the 19th century, rules were codified governing the transit of vessels through the strait. An international commission assumed control of it after World War I; Turkey resumed control in 1936. Two of the world’s longest bridges, completed in 1973 and 1988, span the strait.
Bosporus, Kingdom of the or Cimmerian Bosporus Ancient Greek kingdom, in modern southern Ukraine. It was first settled by Mile¬ sians (6th century bc) at Panticapaeum, which later became the capital. Gradually the kingdom grew to include all of the Crimea. It maintained close ties with Athens in the 5th-3rd century bc, reaching the peak of its power in the 4th century bc. It came under the rule of the kings of Pon- tus after 110 bc. For 300 years it belonged to the Roman Empire, and after ad 342 it was alternately under barbarian and Byzantine control.