A black hole is a celestial body region predicted to exist in the universe based on modern physical theory and astronomical theory.
Historically, the French mechanician Laplace once predicted: "A luminous star with a mass of 250 suns and a diameter of the Earth will not allow any light to leave it due to its gravity. For this reason, the largest luminous objects in the universe cannot be seen by us."
A black hole is formed by the gravitational collapse of a very massive celestial body after its nuclear energy is exhausted and it dies. According to Newton's universal gravity theorem, because the first cosmic velocity of a black hole is too large, even light cannot escape, so it is called a black hole.
The gravitational force in this area is so strong that no matter can escape from this area, and even light is pulled back by its strong gravity. Therefore, the black hole itself will not emit light, but neither will the black hole. Appearing black like other non-luminous objects, the gravity of a black hole can make the light behind it flow around in front of it, making you think it is transparent. Astronomers can find the location of a black hole by observing how matter around it is attracted.
Black holes can be observed with electronic instruments.
Size and mass
Computer simulation of a black hole with a mass 10 times that of the sun. A black hole is formed by the gravitational collapse of a celestial body greater than 3.2 times the mass of the sun (less than 1.4 times the mass of the sun) Mass stars will become white dwarfs). Astronomical observations show that in the centers of many galaxies, including the Milky Way, there are supermassive black holes that exceed the mass of hundreds of millions of times the sun.
Einstein’s general theory of relativity predicts a black hole solution. The simplest spherical symmetry solution is the Schwarzschild metric. This is the solution to Einstein's equations discovered by Karl Schwarzschild in 1915.
According to the Schwarzschild solution, if the radius of a gravitational object is less than a specific value, the object will collapse. This radius is called the Schwarzschild radius. For celestial bodies below this radius, space-time is severely curved, so that all rays emitted by the celestial body, no matter what direction they come from, will be attracted into the center of the celestial body. Because the theory of relativity points out that in any inertial coordinates, the speed of matter cannot exceed the speed of light in vacuum, any material of celestial bodies below the Schwarzschild radius, including the constituent materials of gravitational celestial bodies, will collapse in the central part. A point with theoretically infinite density constitutes a gravitational singularity. Since even light cannot escape the black hole within the Schwarzschild radius, a typical black hole is indeed absolutely "black".
Temperature
The larger the black hole, the lower the temperature.
Characteristics
The currently accepted theory is that there are only three physical quantities that can be measured in black holes: mass, charge, and angular momentum. That is to say: for a black hole, once these three physical quantities are determined, the characteristics of the black hole are uniquely determined. This is called the hairless theorem of black holes, or the uniqueness theorem of black holes. However, this theorem only limits the classical theory and does not deny the possible existence of other quantum charges. Therefore, black holes can coexist with large-area monopoles or cosmic string ***, and carry large-area quantum charges.
The merger of black holes will emit powerful gravitational waves in the form of a beam, and the new black hole will be separated from its original position in the core of the galaxy due to recoil. If the speed is large enough, it may even break away from the parent galaxy [1].
Classification
Classification method one:
Supermassive black hole
So far its traces can be found in the centers of all known galaxies .
The mass is said to be millions to billions of times that of the sun.
Small mass black hole
A black hole will form if its mass is 10 to 20 times the mass of the sun. That is, the core mass left after the supernova explosion is 3 to 15 times the mass of the sun.
Theoretical predictions are that when the mass is more than 40 times that of the sun, a black hole can be formed without a supernova explosion.
Medium-sized black holes
It is inferred that they were formed by the merger of small-mass black holes, and finally became super-massive black holes.
There are still doubts about whether medium-sized black holes actually exist.
Classification method two: Based on the physical properties of the black hole itself (mass, charge, angular momentum):
Black holes that do not rotate and have no charge. Its space-time structure was calculated by Schwarzschild in 1916 and was called Schwarzschild black hole.
A non-rotating charged black hole is called an R-N black hole. The structure of space-time was solved by Reissner and Nordstrom in 1916-1918.
A rotating uncharged black hole is called a Kerr black hole. The structure of space-time was found by Kerr in 1963.
General black holes are called Kerr-Newman black holes. The structure of space-time was solved by Newman in 1965.
Micro black holes
Micro black holes are a type of black hole predicted by theory. There is currently no evidence to support the existence of micro black holes. They were born in the early days of the Big Bang and have a very small mass. According to Hawking's theory, the smaller the mass of a black hole, the faster it "evaporates".
So if microblack holes existed, they must have evaporated by now.
Bermuda, Hong Kong and Taiwan translation Bermuda (English: Bermuda; also known as the Bermuda Islands; formerly known as Somers Island) is located in the North Atlantic and is an autonomous overseas territory of the United Kingdom. It is located at 32°14' to 32°25' north latitude, and 64°38' to 64°53' west longitude. It is about 900 kilometers away from North America, about 1,100 nautical miles northeast of Miami, Florida on the east coast of the United States and Nova Scotia, Canada. About 840 nautical miles southeast of Lifax. The closest landmark is Cape Hatteras in North Carolina, USA, approximately 640 nautical miles (1,030 kilometers) northwest. Bermuda is the oldest British overseas territory, dating back a century or two before the promulgation of the Acts of Union 1707 (Acts of Union 1707) and the establishment of the United Kingdom. The United Nations Decolonization Committee has listed it as one of the 16 non-self-governing territories in the world since 1945.
"Bermuda" generally refers to a single archipelago, consisting of about 138 islands and many reefs, with a total area of ??27.7 square nautical miles (71.7 square kilometers), slightly larger than Manhattan Island in the United States (part of New York City) , with an area of ??22.6 square nautical miles). Seven of the main islands are connected by bridges and causeways, covering an area of ??53 square kilometers. The main island of Bermuda (also known as "Greater Bermuda") is about 35 square kilometers. Some of Bermuda's islands have multiple names (the entire archipelago, along with its two official names, has historically been called "La Garza", "Virgineola" and "Devil's Island"). Although there are not many landmarks, it is common for places to have the same name; for example, there are two islands named "Long Island" and two bays named "Long Bay", and the town of St. George is located in the St. George Borough of St. George Island. In addition, the capital of Bermuda, Hamilton, is located in Pembroke Parish (not Hamilton District) on the main island.
Bermuda has a prosperous economy, relying on the financial industry and tourism. It is known as a "tax haven" and "corporate paradise" and is a world-famous offshore financial center. The local area has a warm tropical climate, beautiful beaches, and often boasts pink sand and turquoise ocean.
History
Main article: History of Bermuda
It is believed that Bermuda was founded in the early 16th century, probably in 1503 by the Spanish explorer Juan Bermuda. de Bermudez first discovered it, but his records gave only a rough description. In 1511, Bermuda and the Spaniard were mentioned in the book "Legatio Babylonica" written by Peter Martyr d'Anghiera. In the same year, Spain added the islands to its nautical charts. Spanish and Portuguese ships used Bermuda as a depot for fresh meat and water. However, legends of ghosts and devils prevent people from settling on "Devil Island" for a long time. It is now believed to have been caused by the shrill call of a bird (possibly a Bermuda petrel) and persistent wind damage (the conditions under which most early travelers arrived).
Bermuda and Gonzales Ferdinando d'Oviedo speculated on Bermuda around 1514-1515, intending to plant pigs on the island as fresh meat futures, which would be sold to passing ships in the future. However, Bermuda's harsh climate discouraged them from landing.
A few years later, a Portuguese ship returning from Santo Domingo squeezed into two rocks on the reef. The crew tried their best to rescue and spent the next four months building a new hull out of Bermuda cypress and returning to the original starting point. One of the stranded crew members allegedly carved the initials "R" and "P" and the year "1543" into a Spanish rock. The initials may be a symbol of "Rex Portugaline". Later, it was misunderstood that it was done by the Spanish, so that the stone was mistakenly named "Spanish Stone".
In the following centuries, some people may have stayed in Bermuda, but no one has yet settled. The first two British colonies in Virginia failed, and King James I of England and James VI of England decided to grant a royal charter to the Virginia Company. In 1609, the company's fleet commander, Admiral Sir George Somers, led the fleet to leave England and go to rescue the Jamestown colony that had been colonized two years ago. Summers gained experience by sailing with Sir Francis Drake and Sir Walter Raleigh. The fleet was destroyed in a storm and the flagship, Sea Venture, was wrecked off Bermuda (as depicted on Bermuda's coat of arms), leaving the survivors to live in new territory. (William Shakespeare's play "The Tempest" may have been influenced by William Strachey's account of the shipwreck.) The British Crown claimed Bermuda, and relevant provisions were added to the Virginia Company's charter.
In 1615, Bermuda was transferred to a new company, the Somers Island Company ("Somers Island" is still the official name of the colony), composed of the same shareholders. The first British coins in the United States were minted here.
In 1610, most of the survivors of the Adventure of the Sea were taken to Jamestown by two Bermuda-made ships. One of the survivors was John Rolfe, who left behind a wife and children who were buried in Bermuda. Later, he married Pocahontas, the daughter of Chief Powhatan, in Jamestown, and Rolfe alone developed Virginia's tobacco industry (logging would become the economic basis of the colony). In 1612, with the arrival of the Plow, the carefully studied colonization of Bermuda finally began.
Due to insufficient land, Bermuda faces problems caused by population growth. During the first two centuries of colonization, the region relied on steady immigration to control the population. Before the American Revolution, there were more than 10,000 Bermudians who immigrated, mainly to the American South. There, England (later known as Great Britain) was replacing Spain as the dominant empire in Europe. Before the end of the 18th century, the steady flow of foreign immigrants had not stopped, and navigation became the only industry. At that time, at least one-third of the island's manpower was at sea at any one time.
However, in the 17th century, the Somers Island Company suppressed the shipbuilding industry because they needed Bermudians to farm to earn income. Bermuda could not be a successful agricultural colony. Bermuda cypress boxes carrying tobacco to England were reportedly worth more than the goods inside. However, the tobacco produced in the Virginia colony was superior to that of Bermuda in both quality and quantity. After the collapse of the Somers Island Company, Bermudians abandoned agriculture and switched to shipbuilding. They replanted native cypress trees (Juniperus bermudiana, also known as "Bermuda cypress") on farmland, and the trees grew rapidly across the island. Bermudians took full advantage of the Turks, clearing forests and conducting the world's largest salt trade. The salt trade became the mainstay of Bermuda's economy over the next century.
Bermuda sailors wanted to trade rather than simply supply salt, but whaling, privateering and merchant trade developed steadily. The speed and maneuverability of the Bermuda sloop were highly valued. At the end of the Battle of Trafalgar, the Bermuda sloop HMS Pickle, one of the fastest ships of the Royal Navy, even brought the good news of victory and Admiral Lord Nelson. News of his death returned to England with all speed.
After the American Revolution, the British Royal Navy established a large shipyard on the island of Ireland in order to improve the seaport. Later, the Navy viewed the bases as strategic assets, and later the bases became more beneficial to the United States (see next paragraph). Bermuda allowed Confederate American blockade runners to anchor briefly before sailing south. Today, a small museum preserves the offices that the Confederate Army used for conspiracy.
In the early 20th century, with the development of modern transportation and communication systems, Bermuda became a popular tourist destination for tourists from the United States, Canada and the United Kingdom. In 1930, the United States enacted the Smoot-Hawley Tariff Act, which interrupted Bermuda's flourishing agricultural export trade (mainly supplying fresh vegetables to the United States) to its trading partners and encouraged Bermuda to develop tourism. Industry. From an economic perspective, tourism is closely followed by the international financial industry.
Politics
Bermuda’s executive is funded by Queen Elizabeth II, with the Governor of Bermuda exercising authority on her behalf. The Queen appoints the Governor-General on the advice of the British Government. Defense and diplomacy are still the responsibility of the United Kingdom, and the authorities must also ensure the effective governance of the Bermuda government. Changes to Bermuda's constitution require British approval.
The Constitution of Bermuda came into effect on June 1, 1967, and was revised in 1989 and 2003. The head of government is the Prime Minister. The cabinet is nominated by the Prime Minister and formally appointed by the Governor-General. The legislative branch consists of a bicameral parliament. The Senate is the upper house and consists of seven members appointed by the Governor-General on the advice of the Prime Minister and the Leader of the Opposition. The House of Representatives is the lower house, with 36 members elected by the people for 5-year terms.
The current Governor is John Vereker, who was appointed on April 11, 2002. The current Prime Minister is Ewart Brown, who defeated former Prime Minister Alex Scot of the Labor Progressive Party at the October 2006 delegates conference. The United Bermuda Party became the opposition party.
The leadership of the Labor Progressive Party has always supported Bermuda's independence from the United Kingdom, but the results of the opinion polls were as expected, and the public did not support the move. The party launched a referendum on independence in 1995, but failed.
Military
The Remembrance Day Military Parade in Hamilton, Bermuda Main article: Bermuda Military
The defense of Bermuda is still the responsibility of the British government.
Bermuda once served as the Western Atlantic headquarters of the British Royal Navy, and the local government used militia to defend the colony until the American Civil War. In the past, the Royal Navy established a base and its shipyards were regularly guarded by soldiers. However, due to excess military strength, it was disbanded following the War of 1812. At the end of the 19th century, a volunteer force was established in Bermuda to provide reserves for military garrisons.
Bermuda is located close to the middle of the North Atlantic and played an important role in the two world wars. The area became a staging point for transatlantic convoys, as well as a naval and (during World War II) air force base. In 1941, the U.S. military passed the Destroyers for Bases Agreement and established naval and air bases by transferring remaining U.S. Navy destroyers to the United Kingdom in exchange for a 99-year lease on Bermuda until the end of the Cold War. The base covers an area of ??5.8 square kilometers (2.25 square miles), most of which was reclaimed from the sea.
For years, the Americans used the airport as a front for aircraft searching for German and Soviet submarines. Canada once operated a wartime naval base, HMCS Somers Isles, at the former British Royal Navy base at Convict Bay. At the same time, St. George also established a radio station at Daniel's Head on the western edge of the islands.
In the 1950s, at the end of World War II, the Royal Navy closed its shipyards and military garrisons. Small supply bases in the United States and bases in the United States and Canada continue to operate within the shipyard. On September 1, 1995, both bases were closed, along with bases in the United Kingdom and Canada. Environmental-related issues have slowed down the U.S.'s progress in returning base land. It was not until 2002 that the United States officially returned the land to the local government.
Today, the Bermuda Army is the only army in Bermuda, a mixed volunteer force formed before the end of the 19th century.
Geography
Bermuda is located in the North Atlantic Ocean, approximately 580 nautical miles (1,074 kilometers) east to southeast from Cape Hatteras on the Outer Banks of North Carolina. , about 590 nautical miles (1,093 kilometers) southeast of Martha's Vineyard (see map). Bermuda has 103 kilometers of coastline. The City of Hamilton and the Town of St. George are the two statutory municipalities of Bermuda. There are also areas called "villages" such as Flatts Village, Tucker's Town and Somerset Village.
Most people misunderstand that Bermuda is located in the tropics. In fact, Bermuda has a subtropical climate that is strongly influenced by the nearby Gulf Stream. Bermuda has a very humid climate, and even though temperatures may seem moderate in the summer, the heat index is high. Winters are very warm, with average daytime temperatures in January and February of around 20°C (68°F). Strong winds and heavy rains can make temperatures feel like they've dropped below freezing, but they rarely actually drop below 10°C (50°F). Rainfall is Bermuda's only source of fresh water, collected from rooftops and watersheds (or pumped from underground ore bodies) and stored in cisterns. Each household usually has at least one water storage tank to consolidate the local water supply.
Economy
Bermuda has a developed international business and economic system. It is an offshore financial center for many foreign companies and a financial export point for insurance and various financial services. Tourism also brings considerable income to Bermuda. Bermuda's per capita income is about 50% higher than that of the United States; "The World Factbook" published by the United States Central Intelligence Agency shows that Bermuda's GDP in 2004 was $45, which means that the total per capita value reached $69,900. In other words, Bermuda has the highest per capita GDP in the world.
Bermuda is considered a premier offshore financial center and the government does not impose direct taxes on personal or corporate income. The local tax system relies on import duties, salaries tax and consumption tax. The relevant policies have brought advantages to international insurance companies, and Bermuda is regarded as the world's reinsurance center. [Source Request] Approximately 400 international companies represented by the Association of Bermuda International Companies (ABIC) are naturally based in Bermuda. Today, there are more than 1,500 tax-free companies and international companies registered in Bermuda.
Tourism is Bermuda’s second largest industry, with most visitors coming from the United States, Canada and the United Kingdom. They will disembark at the local Bermuda International Airport.
Bermuda adopts the Bermudian dollar, and its currency has been pegged to the US dollar. Within the islands, U.S. dollar bills and coins are interchangeable with Bermudian currency. Bermuda banknotes feature Queen Elizabeth II.
Population
The total population of Bermuda is 65,365 (estimated in July 2005), of which whites account for 34.1%, blacks account for 54.8%, and mixed races account for 6.4%. Has a small but growing Asian ethnic population.
A part of the population retains Portuguese traditions, based on immigration from the Portuguese Islands (especially the Azores) in the last century. This may be traced back to the Madeira family in the 1840s [source requested].
In the recent census [source request], racial identity became an issue; [source request] The demographic data described in the above paragraph may be misleading. The island has a small black population of various ancestry, particularly European and Native American ancestry. Portuguese-Bermudians are often regarded as an independent ethnic group, similar to Latinos in the United States. Immigrants to the Portuguese Islands included blacks from the Cape Verde Islands, as well as Portuguese who intermarried with whites and blacks from Bermuda. Therefore, many islanders who inherit Portuguese ancestry, traditions and Portuguese names are not counted as 10% or more of the population, but are typically classified as "Portuguese".
Native Americans have once again attracted attention, especially in St. David's, where many residents identify themselves as various North American Indians who were sold to Bermuda as slaves during the first century of colonization.
In the last century, in addition to large-scale immigrants from Portugal, immigrants from Caribbean countries also continued to emerge.
There are thousands of foreign workers, mainly from the United Kingdom, Canada, the West Indies and the United States, who also live in Bermuda, mainly engaged in industries that require professional skills, such as accounting, finance and insurance. The remainder are employed in a variety of industries, including hotels, restaurants, construction, gardening, and more. According to the employed population figures released by the government in 2005, of the total labor force of 38,947, 11,223 (29%) were non-Bermuda citizens.
St. David's Lighthouse, one of Bermuda's tourist attractions Are some of Bermuda's tourist attractions:
Bermuda Aquarium, Museum and Zoo[1]
Bermuda Maritime Museum
Botanical Gardens
City Hall
Crisson Jewellers
Crystal, Fantasy and Leamington Caves
Gibbs Hill Lighthouse
Royal Navy Shipbuilding Factory (Royal Naval Dockyard)
St David's Lighthouse
St George's
St Peter's Church
Swizzle Inn
Holidays
Dates and Holiday Notes
New Year's Day on January 1st
Perhaps on Good Friday Bermudians will fly homemade kites to celebrate Easter
Bermuda Day on May 24 was originally designated as Empire Day on the birthday of Queen Victoria; it was later renamed "Bermuda Day" to officially celebrate the traditions and culture of the islands
The second Monday in June The Queen's Birthday
The last Thursday in July or Liberation Day, the first Thursday in August, the first day of the World Cup
The first Friday in August, Somer's Day, the day after the World Cup
< p>Labor Day on the first Monday in SeptemberMemorial Day on November 11
Christmas on December 25
December 26 Boxing Day
Culture
Bermuda's culture was greatly influenced by the British colonists and inherited most of the British traditions and customs; due to its proximity to the United States, Bermuda was also affected by it. The majority of Bermuda's population is descended from African slaves.
Dance and music are the essence of Bermuda culture, and many dances are influenced by Native American immigrants and African slaves. Caribbean influences dominate the Bermuda hobby.
Celebrities
(in alphabetical order by surname)
Clyde Best, the first English footballer (late 1960s-1970s)
Donald Henry "Bob" Burns, the Guinness Green World Record holder with the highest male voice
G. K. Butterfield, member of the U.S. House of Representatives (D-NC), former High Court judge, and judge of the National Court of Final Appeal
< p>Earl Cameron, entertainerDiana Dill, entertainer, mother of Michael and Joel Douglas
Michael Douglas, entertainer/director
Glyn Charles Anglim Gilbert, major general , the highest-ranked Bermudian soldier
Shaun Goater, former Manchester City striker
Edward Harris, archaeologist and founder of the Harris matrix method of archaeological stratigraphy
Lance Hayward, jazz pianist
Clarence Hill, Olympic boxing bronze medalist
Lena Headey, English entertainer
Heather Nova, musician
< p>Mary Prince, slave whose account of History of Mary Prince helped end slavery in the British EmpireArthur Rankin, Jr., producer, director, partner of Rankin/Bass Productions People
Clarence "Nicky" Saunders, Commonwealth Games high jump gold medalist
Gina Swainson, former Miss World (1979-1980)
Edward "Teddy " Tucker, diver, treasure hunter
David B. Wingate, naturalist
Collie Buddz, reggae/dancehall artist
Bermuda Triangle Triangle
Also known as the Devil's Triangle[1] and Death Hell.
It is said that more than 50 ships and more than 20 aircraft have mysteriously disappeared here. The slightly triangular-shaped area is located between the southern coast of the United States, Bermuda, and the Greater Antilles. Unexplained events in the area date back to the mid-19th century. Sometimes ships disappear for unknown reasons, and sometimes they disappear without even sending a distress signal. A prominent example is the disappearance of the US Navy auxiliary ship "One Eye" carrying manganese ore in March 1918, which remains a mystery to this day. In 1945, five U.S. bombers took off from the Fort Lauderdale Air Force Base in Florida. They radioed that they were in distress during a training flight. Then the communication gradually weakened and disappeared, and the rescue team also disappeared.
Bermuda is a world-famous place located about 600 kilometers east of North Carolina in the United States. The specific geographical location of the Bermuda Triangle refers to the triangular area formed by the connection of Bermuda Islands, Miami (Florida Peninsula, USA) and San Juan (Puerto Rico Island) in the Atlantic Ocean, covering an area of ??400,000 square miles. The Baimu Triangle is an archipelago composed of more than 360 islands. These islands lie like a circular ring on the Atlantic Ocean. Because there is a warm current passing between Bermuda and the American continent, the climate here is mild and spring is like spring all year round. The trees are evergreen and the flowers are in full bloom. Bermuda is also known as the most isolated island on earth. Because it is hundreds of miles away from the nearest land, Bermuda is surrounded by a vast ocean, with beautiful scenery of blue sky, green water, white gulls flying, and the fragrance of flowers.
However, the reason why Bermuda is famous is not because of its beautiful island scenery, but when people think of Bermuda, they will think of the terrifying and mysterious "Bermuda Triangle". According to legend, ships or planes sailing here often disappear mysteriously. Not to mention finding out the cause afterwards, even the wreckage of the ships and planes cannot be found. So that when the most experienced sailors or pilots pass here, they have no intention of admiring the beautiful and picturesque sea scenery. Instead, they are trembling and fearful, fearing that they will encounter bad luck and be buried in the belly of the fish for no apparent reason. Today, the Bermuda Triangle has become synonymous with mysterious and incomprehensible disappearances.