All articles starting with B
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Black helicopter
Black helicopter: conspiracy-theory term for unmarked dark helicopters alleged to be a UN or federal takeover force; also real dark military and law enforcement aircraft, including the CIA's Hughes 500P Quiet One.
Black Hills
The Black Hills (He Sapa) are a 1.2-million-acre Laramide domal uplift in southwest South Dakota and Wyoming, with a Precambrian granite core, concentric sedimentary rings, Mount Rushmore, Wind and Jewel caves, and unceded Sioux treaty land.
Black Hills Expedition
The Black Hills Expedition was a United States Army reconnaissance led by George Armstrong Custer in 1874 that confirmed gold in the Black Hills, land guaranteed to the Lakota.
Black Hills Gold Rush
The Black Hills Gold Rush was the influx of prospectors into the Black Hills of Dakota Territory after Custer's 1874 expedition confirmed gold, producing mining camps such as Deadwood.
Black Hippy
Black Hippy: American hip hop supergroup from South Los Angeles on Top Dawg Entertainment, members Kendrick Lamar, Jay Rock, ScHoolboy Q, Ab-Soul; active 2008–2022 with a 2024 reunion, never released a group album.
Black Hispanic and Latino Americans
Black Hispanic and Latino Americans, or Afro-Latinos, are U.S. residents identifying as both Black and Hispanic or Latino; about 6 million adults in 2020, 12% of adult Latinos, mostly Puerto Rican or Dominican origin.
Black History Month
Black History Month, or African American History Month, is the February U.S. observance of Black history, founded by Carter G. Woodson as Negro History Week in 1926 and nationally recognized since 1976.
Black hole
A black hole is a region of spacetime where gravity within the event horizon prevents anything, even light, from escaping; it forms when matter collapses densely enough.
Black hole bomb
The black hole bomb is a theoretical instability where waves amplified by a rotating black hole's superradiance grow exponentially, proposed by Press and Teukolsky in 1972.
Black hole complementarity
Black hole complementarity is a 1993 proposal in quantum gravity by Susskind, Thorlacius, and Uglum holding that outside and inside observers see complementary descriptions of the same information.
Black hole entropy in loop quantum gravity
In loop quantum gravity, black hole entropy is derived by counting quantum geometric states puncturing a horizon, reproducing the Bekenstein–Hawking area law with the Immirzi parameter fixed accordingly.
Black Hole Explorer
Black Hole Explorer, or BHEX, is a proposed NASA space VLBI mission to image supermassive black holes like M87 and measure the photon ring, targeted for launch in 2031.
Black hole feedback
Black hole feedback is the transfer of energy from an accreting supermassive black hole to gas in its host galaxy, altering star formation and black hole growth.
Black hole information paradox
The black hole information paradox is a conflict between quantum mechanics and general relativity: Hawking's 1976 calculation suggests evaporating black holes destroy information, which unitary quantum evolution forbids.
Black hole microstate counting in string theory
Black hole microstate counting in string theory derives black hole entropy by counting quantum states of D-brane bound states, begun by Strominger and Vafa in 1996.
Black Hole of Calcutta
The Black Hole of Calcutta was a Fort William dungeon where, per Holwell's sole 1758 account, 146 prisoners were held on 20 June 1756 and 123 died; historians dispute the numbers, estimates ranging from nine to sixty-nine.
Black hole remnant
A black hole remnant is a hypothetical stable or long-lived object left when Hawking evaporation stops, proposed to preserve information and avoid the information loss paradox.
Black hole ringdown
Black hole ringdown is the final phase of a black hole merger, in which the settling remnant emits gravitational waves at quasinormal modes fixed by its mass and spin.
Black hole seed
A black hole seed is the initial black hole from which a supermassive black hole grows, formed either from the first stars or by direct collapse of a gas cloud.
Black hole shadow
A black hole shadow is the dark, roughly circular region in an image of a black hole surrounded by glowing matter, first predicted by James Bardeen in 1973.
Black hole spectroscopy
Black hole spectroscopy measures the quasinormal-mode vibrational frequencies of newly formed black holes from gravitational-wave data, testing the no-hair theorem; it began with GW150914 in 2015.
Black hole spin
Black hole spin is the angular momentum of a black hole, expressed as a dimensionless number from 0 to 1, and one of only two quantities that fully characterize it.
Black Hole Sun
Black Hole Sun: 1994 Soundgarden song written by Chris Cornell, third single from Superunknown, Grammy-winning biggest hit, over 1 billion Spotify streams.
Black hole thermodynamics
Black hole thermodynamics is the field of physics treating black holes as thermodynamic systems, with Bekenstein–Hawking entropy proportional to horizon area and temperature from Hawking radiation.
Black Holes and Revelations
Black Holes and Revelations is Muse's fourth studio album (2006, Warner Bros.), co-produced with Rich Costey. It debuted at UK No. 1 with 115,144 first-week copies, went double platinum, hit US No. 9, and spawned Supermassive Black Hole, Starlight, and Knights of Cydonia.
Black holes in globular clusters
Black holes in globular clusters are stellar-mass black holes of about 10 solar masses inside dense, old star clusters, where dynamics decide whether they sink, merge, or are ejected.
Black horror
Black horror is a horror-fiction and film genre centering Blackness, Black history, and racism as the source of terror. Also called Afrohorror; spans Birth of a Nation (1915), Night of the Living Dead, Blacula, Get Out, and Sinners, with scholarship by Robin R. Means Coleman.
Black house spider
Black house spider (Badumna insignis, window spider), an Australian Desidae spider building lacy cribellate sheet webs with funnel-like retreats on bark and window frames; harmless, seldom bites, often mistaken for funnel-webs.
Black Hundreds (Чёрная сотня)
Black Hundreds (Чёрная сотня), right-monarchist parties of the Russian Empire formed during the 1905–1907 revolution to defend unlimited autocracy, Orthodoxy, and Russian dominance; largest was the Union of the Russian People; known for pogroms and assassinations.
Black Iberian pig
Black Iberian pig (cerdo ibérico), also porco preto, a rustic dark-skinned pig breed from the Iberian Peninsula famed for acorn-fed (montanera) jamón ibérico, high oleic-acid fat, and regulated Duroc crossbreeding.