Stephen Hawking

Stephen William Hawking, CH, CBE, FRS, FRSA (born 8 January 1942) is a British theoretical physicist, whose scientific career spans over forty years. His books and public appearances have made him an academic celebrity and he is an Honorary Fellow of the Royal Society of Arts, a lifetime member of the Pontifical Academy of Sciences, and in 2009 was awarded the Presidential Medal of Freedom, the highest civilian award in the United States.
Hawking was the Lucasian Professor of Mathematics at the University of Cambridge for thirty years, taking up the post in 1979 and retiring on 1 October 2009. He is also a Fellow of Gonville and Caius College, Cambridge and a Distinguished Research Chair at the Perimeter Institute for Theoretical Physics in Waterloo, Ontario.He is known for his contributions to the fields of cosmology and quantum gravity, especially in the context of black holes. He has also achieved success with works of popular science in which he discusses his own theories and cosmology in general; these include the runaway best seller A Brief History of Time, which stayed on the British Sunday Times bestsellers list for a record-breaking 237 weeks.
Hawking's key scientific works to date have included providing, with Roger Penrose, theorems regarding gravitational singularities in the framework of general relativity, and the theoretical prediction that black holes should emit radiation, which is today known as Hawking radiation (or sometimes as Bekenstein–Hawking radiation).
Hawking has a neuro-muscular dystrophy that is related to amyotrophic lateral sclerosis, a condition that has progressed over the years and has left him almost completely paralysed.

Early life and education

Stephen Hawking was born on 8 January 1942 to Dr. Frank Hawking, a research biologist, and Isobel Hawking. He had two younger sisters, Philippa and Mary, and an adopted brother, Edward.[11] Though Hawking's parents were living in North London, they moved to Oxford while his mother was pregnant with Stephen, desiring a safer location for the birth of their first child (London was under attack at the time by the Luftwaffe).According to Hawking, a German V-2 missile struck only a few streets away.
After Hawking was born, the family moved back to London, where his father headed the division of parasitology at the National Institute for Medical Research. In 1950, Hawking and his family moved to St Albans, Hertfordshire, where he attended St Albans High School for Girls from 1950 to 1953. (At that time, boys could attend the Girls school until the age of ten.) From the age of eleven, he attended St Albans School, where he was a good, but not exceptional, student. When asked later to name a teacher who had inspired him, Hawking named his mathematics teacher, Dikran Tahta. He maintains his connection with the school, giving his name to one of the four houses and to an extracurricular science lecture series. He has visited to deliver one of the lectures and has also granted a lengthy interview to pupils working on the school magazine, The Albanian.
Hawking was always interested in science. Inspired by his mathematics teacher, he originally wanted to study the subject at university. However, Hawking's father wanted him to apply to University College, Oxford, where his father had attended. As University College did not have a mathematics fellow at that time, it would not accept applications from students who wished to read that discipline. Hawking therefore applied to read natural sciences, in which he gained a scholarship. Once at University College, Hawking specialised in physics. His interests during this time were in thermodynamics, relativity, and quantum mechanics. His physics tutor, Robert Berman, later said in The New York Times Magazine:
It was only necessary for him to know that something could be done, and he could do it without looking to see how other people did it. He didn't have very many books, and he didn't take notes. Of course, his mind was completely different from all of his contemporaries.
Hawking was passing, but his unimpressive study habits resulted in a final examination score on the borderline between first and second class honours, making an "oral examination" necessary. Berman said of the oral examination:
And of course the examiners then were intelligent enough to realize they were talking to someone far more clever than most of themselves.
After receiving his B.A. degree at Oxford in 1962, he stayed to study astronomy. He decided to leave when he found that studying sunspots, which was all the observatory was equipped for, did not appeal to him and that he was more interested in theory than in observation. He left Oxford for Trinity Hall, Cambridge, where he engaged in the study of theoretical astronomy and cosmology.




Career in theoretical physics

Almost as soon as he arrived at Cambridge, he started developing symptoms of amyotrophic lateral sclerosis (known colloquially in the United States as Lou Gehrig's disease), a type of motor neuron disease which would cost him almost all neuromuscular control. During his first two years at Cambridge, he did not distinguish himself, but, after the disease had stabilised and with the help of his doctoral tutor, Dennis William Sciama, he returned to working on his Ph.D.
Hawking was elected as one of the youngest Fellows of the Royal Society in 1974, was created a Commander of the Order of the British Empire in 1982, and became a Companion of Honour in 1989. Hawking is a member of the Board of Sponsors of the Bulletin of the Atomic Scientists.
Hawking's achievements were made despite the increasing paralysis caused by the ALS. By 1974, he was unable to feed himself or get out of bed. His speech became slurred so that he could only be understood by people who knew him well. In 1985, he caught pneumonia and had to have a tracheotomy, which made him unable to speak at all. A Cambridge scientist built a device that enables Hawking to write onto a computer with small movements of his body, and then have a voice synthesizer speak what he has typed.
Research fields


Hawking in Cambridge
Hawking's principal fields of research are theoretical cosmology and quantum gravity.
In the late 1960s, he and his Cambridge friend and colleague, Roger Penrose, applied a new, complex mathematical model they had created from Albert Einstein's general theory of relativity. This led, in 1970, to Hawking proving the first of many singularity theorems; such theorems provide a set of sufficient conditions for the existence of a singularity in space-time. This work showed that, far from being mathematical curiosities which appear only in special cases, singularities are a fairly generic feature of general relativity.
He supplied a mathematical proof, along with Brandon Carter, Werner Israel and D. Robinson, of John Wheeler's "No-Hair Theorem" – namely, that any black hole is fully described by the three properties of mass, angular momentum, and electric charge.
Hawking also suggested that, upon analysis of gamma ray emissions, after the Big Bang, primordial mini black holes were formed. With Bardeen and Carter, he proposed the four laws of black hole mechanics, drawing an analogy with thermodynamics. In 1974, he calculated that black holes should thermally create and emit subatomic particles, known today as Bekenstein-Hawking radiation, until they exhaust their energy and evaporate.
In collaboration with Jim Hartle, Hawking developed a model in which the universe had no boundary in space-time, replacing the initial singularity of the classical Big Bang models with a region akin to the North Pole: one cannot travel north of the North Pole, as there is no boundary. While originally the no-boundary proposal predicted a closed universe, discussions with Neil Turok led to the realisation that the no-boundary proposal is also consistent with a universe which is not closed.
Along with Thomas Hertog at CERN, in 2006 Hawking proposed a theory of "top-down cosmology," which says that the universe had no unique initial state, and therefore it is inappropriate for physicists to attempt to formulate a theory that predicts the universe's current configuration from one particular initial state. Top-down cosmology posits that in some sense, the present "selects" the past from a superposition of many possible histories. In doing so, the theory suggests a possible resolution of the fine-tuning question: It is inevitable that we find our universe's present physical constants, as the current universe "selects" only those past histories that led to the present conditions. In this way, top-down cosmology provides an anthropic explanation for why we find ourselves in a universe that allows matter and life, without invoking an ensemble of multiple universes.
Hawking's many other scientific investigations have included the study of quantum cosmology, cosmic inflation, helium production in anisotropic Big Bang universes, large N cosmology, the density matrix of the universe, topology and structure of the universe, baby universes, Yang-Mills instantons and the S matrix, anti de Sitter space, quantum entanglement and entropy, the nature of space and time, including the arrow of time, spacetime foam, string theory, supergravity, Euclidean quantum gravity, the gravitational Hamiltonian, Brans-Dicke and Hoyle-Narlikar theories of gravitation, gravitational radiation, and wormholes.
At a George Washington University lecture in honour of NASA's fiftieth anniversary, Hawking theorised on the existence of extraterrestrial life, believing that "primitive life is very common and intelligent life is fairly rare."

Thorne–Hawking–Preskill bet

U.S. President Barack Obama talks with Stephen Hawking in the Blue Room of the White House before a ceremony presenting him and fifteen others the Presidential Medal of Freedom on August 12, 2009. The Medal of Freedom is the nation's highest civilian honour.
Hawking was in the news in July 2004 for presenting a new theory about black holes which goes against his own long-held belief about their behaviour, thus losing a bet he made with Kip Thorne and John Preskill of Caltech. Classically, it can be shown that information crossing the event horizon of a black hole is lost to our universe, and that thus all black holes are identical beyond their mass, electrical charge and angular velocity (the "no hair theorem"). The problem with this theorem is that it implies the black hole will emit the same radiation regardless of what goes into it, and as a consequence that if a pure quantum state is thrown into a black hole, an "ordinary" mixed state will be returned. This runs counter to the rules of quantum mechanics and is known as the black hole information paradox.

Human spaceflight
At the fiftieth anniversary of NASA in 2008, Hawking gave a keynote speech on the final frontier exhorting and inspiring the space technology community on why we (the human race) explore space.At the celebration of his sixty-fifth birthday on 8 January 2007, Hawking announced his plan to take a zero-gravity flight in 2007 to prepare for a sub-orbital spaceflight in 2009 on Virgin Galactic's space service. Billionaire Richard Branson pledged to pay all expenses for the latter, costing an estimated £100,000.Stephen Hawking's zero-gravity flight in a "Vomit Comet" of Zero Gravity Corporation, during which he experienced weightlessness eight times, took place on 26 April 2007. He became the first quadriplegic to float in zero-gravity. This was the first time in forty years that he moved freely, without his wheelchair. The fee is normally US$3,750 for 10–15 plunges, but Hawking was not required to pay the fee. A bit of a futurist, Hawking was quoted before the flight saying:
Many people have asked me why I am taking this flight. I am doing it for many reasons. First of all, I believe that life on Earth is at an ever-increasing risk of being wiped out by a disaster such as sudden nuclear war, a genetically engineered virus, or other dangers. I think the human race has no future if it doesn't go into space. I therefore want to encourage public interest in space.
In an interview with The Daily Telegraph, he suggested that space was the Earth's long term hope. He continued this theme at a 2008 Charlie Rose interview.
Existence and nature of extraterrestrial life
Hawking has indicated that he is almost certain that alien life exists in other parts of the universe and uses a mathematical basis for his assumptions. "To my mathematical brain, the numbers alone make thinking about aliens perfectly rational. The real challenge is to work out what aliens might actually be like." He believes alien life not only certainly exists in planets but perhaps even in other places, like within stars or even floating in outer space. He also warns that a few of these species might be intelligent and threaten Earth. Contact with such species might be devastating for humanity. "If aliens visit us, the outcome would be much as when Columbus landed in America, which didn't turn out well for the Native Americans," he said. He advocated that, rather than try to establish contact, man should try to avoid contact with alien life forms.

Illness

Hawking on 5 May 2006, during the press conference at the Bibliothèque nationale de France to inaugurate the Laboratory of Astronomy and Particles in Paris and the French release of his work God Created the Integers
Stephen Hawking is severely disabled by motor neuron disease also known as amyotrophic lateral sclerosis (ALS). Hawking's illness is markedly different from typical ALS in the fact that his form of ALS would make for the most protracted case ever documented. A survival for more than ten years after diagnosis is uncommon for ALS; the longest documented durations are thirty-two and thirty-nine years and these cases were termed benign because of the lack of the typical progressive course.
When he was young, he enjoyed riding horses and playing with other children. At Oxford, he coxed a rowing team, which, he stated, helped relieve his immense boredom at the university. Symptoms of the disorder first appeared while he was enrolled at University of Cambridge; he lost his balance and fell down a flight of stairs, hitting his head. Worried that he would lose his genius, he took the Mensa test to verify that his intellectual abilities were intact. The diagnosis of motor neuron disease came when Hawking was 21, shortly before his first marriage, and doctors said he would not survive more than two or three years. Hawking gradually lost the use of his arms, legs, and voice, and as of 2009 has been almost completely paralysed.
During a visit to the research centre CERN in Geneva in 1985, Hawking contracted pneumonia, which in his condition was life-threatening as it further restricted his already limited respiratory capacity. He had an emergency tracheotomy, and as a result lost what remained of his ability to speak. He has since used an electronic voice synthesizer to communicate.
The DECtalk DTC01 voice synthesizer he uses, which has an American English accent, is no longer being produced. Asked why he has still kept it after so many years, Hawking mentioned that he has not heard a voice he likes better and that he identifies with it. Hawking is said to be looking for a replacement since, aside from being obsolete, the synthesizer is both large and fragile by current standards. As of mid 2009, he was said to be using NeoSpeech's VoiceText speech synthesizer.
In Hawking's many media appearances, he appears to speak fluently through his synthesizer, but in reality, it is a tedious drawn-out process. Hawking's setup uses a predictive text entry system, which requires only the first few characters in order to auto-complete the word, but as he is only able to use his cheek for data entry, constructing complete sentences takes time. His speeches are prepared in advance, but having a live conversation with him provides insight as to the complexity and work involved. During a Technology, Entertainment, & Design Conference talk, it took him seven minutes to answer a question.
He describes himself as lucky despite his disease. Its slow progression has allowed him time to make influential discoveries and has not hindered him from having, in his own words, "a very attractive family." When his wife, Jane, was asked why she decided to marry a man with a three-year life expectancy, she responded, "Those were the days of atomic gloom and doom, so we all had a rather short life expectancy."
Wikinews has related news: Scientist Stephen Hawking rushed to hospital in ambulance
On 20 April 2009, Cambridge University released a statement saying that Hawking was "very ill" with a chest infection, and was admitted to Addenbrooke's Hospital. The following day, it was reported that his new condition is "comfortable" and he should make a full recovery from the infection.

Stephen Hawking in popular culture
Hawking has played himself on numerous television shows and has been portrayed in many more. He has played himself on a Red Dwarf anniversary special, played a hologram of himself on the episode "Descent" of Star Trek: The Next Generation, appeared in a skit on Late Night with Conan O'Brien, and appeared on the Discovery Channel special Alien Planet. He has also played himself in several episodes of The Simpsons and Futurama. When he was portrayed on episodes of Family Guy, the voice was actually done by a speech synthesizer on a Macintosh computer, according to DVD commentary. In The Fairly OddParents, it is mentioned that he was Denzel Croker's college roommate. He has also appeared in an episode of the Dilbert cartoon. His actual synthesizer voice was used on parts of the Pink Floyd song "Keep Talking" from the 1994 album The Division Bell, as well as on Turbonegro's "Intro: The Party Zone" on their 2005 album Party Animals, Wolfsheim's "Kein Zurück (Oliver Pinelli Mix)". As well as being fictionalised as nerdcore hip hop artist MC Hawking, he was impersonated in duet with Richard Cheese on a cover of "The Girl Is Mine". In 2008, Hawking was the subject of and featured in the documentary series Stephen Hawking, Master of the Universe for Channel 4. He was also portrayed in the movie Superhero Movie by Robert Joy. In the TV series Dark Angel Logan's technology savvy colleague Sebastian is characterized with many similarities to the actual physicist. In September 2008, Hawking presided over the unveiling of the 'Chronophage' (time-eating) Corpus Clock at Corpus Christi College Cambridge.
Recognition

Acclaim
On 19 December 2007, a statue of Hawking by renowned late artist Ian Walters was unveiled at the Centre for Theoretical Cosmology, University of Cambridge. In May 2008 the statue of Hawking was unveiled at the African Institute for Mathematical Sciences in Cape Town. The Stephen W. Hawking Science Museum in San Salvador, El Salvador is named in honour of Stephen Hawking, citing his scientific distinction and perseverance in dealing with adversity. Stephen Hawking Building in Cambridge, opened on 17 April 2007. The building belongs to Gonville and Caius College and is used as an undergraduate accommodation and conference facility.

Distinctions
Hawking's belief that the lay person should have access to his work led him to write a series of popular science books in addition to his academic work. The first of these, A Brief History of Time, was published on 1 April 1988 by Hawking, his family and friends, and some leading physicists. It surprisingly became a best-seller and was followed by The Universe in a Nutshell (2001). Both books have remained highly popular all over the world. A collection of essays titled Black Holes and Baby Universes (1993) was also popular. His most recent book, A Briefer History of Time (2005), co-written by Leonard Mlodinow, aims to update his earlier works and make them accessible to an even wider audience. He and his daughter, Lucy Hawking, have recently published a children's book focusing on science that has been described to be "like Harry Potter, but without the magic." This book is called George's Secret Key to the Universe and includes information on Hawking radiation.
Hawking is also known for his wit; he is famous for his oft-made statement, "When I hear of Schrödinger's cat, I reach for my pistol." This was a deliberately ironic paraphrase of "Whenever I hear the word culture... I release the safety-catch of my Browning", from the play Schlageter (Act 1, Scene 1) by German playwright and Nazi Poet Laureate Hanns Johst. His wit has both entertained the non-specialist public and helped them to understand complex questions. Asked in October 2005 on the British daytime chat show Richard & Judy, to explain his assertion that the question "What came before the Big Bang?" was meaningless, he compared it to asking "What lies north of the North Pole?"
Hawking has generally avoided talking about politics at length, but he has appeared on a political broadcast for the United Kingdom's Labour Party. He supports the children's charity SOS Children's Villages UK.

Awards and honours

1975 Eddington Medal
1976 Hughes Medal of the Royal Society
1979 Albert Einstein Medal
1981 Franklin Medal
1982 Order of the British Empire (Commander)
1985 Gold Medal of the Royal Astronomical Society
1986 Member of the Pontifical Academy of Sciences
1988 Wolf Prize in Physics
1989 Prince of Asturias Awards in Concord
1989 Companion of Honour
1999 Julius Edgar Lilienfeld Prize of the American Physical Society
2003 Michelson Morley Award of Case Western Reserve University
2006 Copley Medal of the Royal Society
2008 Fonseca Price of the University of Santiago de Compostela
2009 Presidential Medal of Freedom, the highest civilian honour in the United States

Personal life

Hawking revealed that he did not see much point in obtaining a doctorate if he were to die soon. Hawking later said that the real turning point was his 1965 marriage to Jane Wilde, a language student. After gaining his Ph.D. at Trinity Hall, Stephen became first a Research Fellow, and later on a Professorial Fellow at Gonville and Caius College.
Jane Hawking (née Wilde), Hawking's first wife, cared for him until 1991 when the couple separated, reportedly due to the pressures of fame and his increasing disability. They had three children: Robert (b. 1967), Lucy (b. 1969), and Timothy (b. 1979). Hawking then married his nurse, Elaine Mason (who was previously married to David Mason, the designer of the first version of Hawking's talking computer), in 1995. In October 2006, Hawking filed for divorce from his second wife.
In 1999, Jane Hawking published a memoir, Music to Move the Stars, detailing her own long-term relationship with a family friend whom she later married. Hawking's daughter, Lucy, is a novelist. Their oldest son, Robert, emigrated to the United States, married, and has one child, George Edward Hawking. Reportedly, Hawking and his first family were reconciled in 2007.
Religious views
Hawking takes an agnostic position on matters of religion. He has repeatedly used the word "God" (in metaphorical meanings) to illustrate points made in his books and public speeches. His ex-wife, Jane, however, said during their divorce proceedings that he was an atheist. Hawking has stated that he is "not religious in the normal sense" and he believes that "the universe is governed by the laws of science. The laws may have been decreed by God, but God does not intervene to break the laws."
Selected publications

Technical
Singularities in Collapsing Stars and Expanding Universes with Dennis William Sciama, 1969 Comments on Astrophysics and Space Physics Vol 1 #1
The Nature of Space and Time with Roger Penrose, foreword by Michael Atiyah, New Jersey: Princeton University Press, 1996, ISBN 0-691-05084-8
The Large Scale Structure of Spacetime with George Ellis, 1973 ISBN 0521099064
The Large, the Small, and the Human Mind, (with Abner Shimony, Nancy Cartwright, and Roger Penrose), Cambridge University Press, 1997, ISBN 0-521-56330-5 (hardback), ISBN 0-521-65538-2 (paperback), Canto edition: ISBN 0-521-78572-3
Information Loss in Black Holes, Cambridge University Press, 2005
God Created the Integers: The Mathematical Breakthroughs That Changed History, Running Press, 2005 ISBN 0762419229
Popular
A Brief History of Time, (Bantam Press 1988) ISBN 055305340X
Black Holes and Baby Universes and Other Essays, (Bantam Books 1993) ISBN 0553374117
The Universe in a Nutshell, (Bantam Press 2001) ISBN 055380202X
On The Shoulders of Giants. The Great Works of Physics and Astronomy, (Running Press 2002) ISBN 076241698X
A Briefer History of Time, (Bantam Books 2005) ISBN 0553804367
Footnote: On Hawking's website, he denounces the unauthorised publication of The Theory of Everything and asks consumers to be aware that he was not involved in its creation.
Children's fiction
These are co-written with his daughter Lucy.
George's Secret Key to the Universe, (Random House, 2007) ISBN 9780385612708
George's Cosmic Treasure Hunt, (Simon & Schuster, 2009) ISBN 9781416986713
Films and series
A Brief History of Time
Stephen Hawking's Universe
Horizon: The Hawking Paradox
Masters of Science Fiction
Stephen Hawking: Master of the Universe
Into The Universe with Stephen Hawking
A list of Hawking's publications through the year 2002 is available on his website.
See also

Basic concepts of quantum mechanics
George Ellis
Gravitational singularity
Many-worlds interpretation, or flexiverse
Stephen Hawking in popular culture
Susskind–Hawking battle
Sydney Selwyn, another distinguished British scientist who suffered from a progressively debilitating illness
Source:wikipedia
Sponsor:Click2.info

Mount Rushmore

Mount Rushmore National Memorial, near Keystone, South Dakota, is a monumental granite sculpture by Gutzon Borglum (1867–1941), located within the United States Presidential Memorial that represents the first 150 years of the history of the United States of America with 60-foot (18 m) sculptures of the heads of former United States presidents (left to right): George Washington (1732–1799), Thomas Jefferson (1743–1826), Theodore Roosevelt (1858–1919), and Abraham Lincoln (1809–1865). The entire memorial covers 1,278.45 acres (5.17 km2) and is 5,725 feet (1,745 m) above sea level. It is managed by the National Park Service, a bureau of the United States Department of the Interior. The memorial attracts approximately two million people annually.

History

See also: Construction of Mount Rushmore


The carving of Mount Rushmore involved the use of dynamite, followed by the process of "honeycombing". About two million tons of rock were blasted off the mountainside.
Originally known to the Lakota Sioux as Six Grandfathers, the mountain was renamed after Charles E. Rushmore, a prominent New York lawyer, during an expedition in 1885. At first, the project of carving Rushmore was undertaken to increase tourism in the Black Hills region of South Dakota. After long negotiations involving a Congressional delegation and President Calvin Coolidge, the project received Congressional approval. The carving started in 1927, and ended in 1941 with some injuries and no fatalities.
As Six Grandfathers, the mountain was part of the route that Lakota leader Black Elk took in a spiritual journey that culminated at Harney Peak. Following a series of military campaigns from 1876 to 1877, the United States asserted control over the area, a claim that is still disputed on the basis of the 1868 Treaty of Fort Laramie (see section "Controversy" below). Among white American settlers, the peak was known variously as Cougar Mountain, Sugarloaf Mountain, Slaughterhouse Mountain, and Keystone Cliffs. It was named Mount Rushmore during a prospecting expedition by Rushmore, David Swanzey (whose wife Carrie was the sister of author Laura Ingalls Wilder), and Bill Challis.
Historian Doane Robinson conceived the idea for Mount Rushmore in 1923 to promote tourism in South Dakota. In 1924, Robinson persuaded sculptor Gutzon Borglum to travel to the Black Hills region to ensure that the carving could be accomplished. Borglum had been involved in sculpting the Confederate Memorial Carving, a massive bas-relief memorial to Confederate leaders on Stone Mountain in Georgia, but was in disagreement with the officials there. The original plan was to perform the carvings in granite pillars known as the Needles. However, Borglum realized that the eroded Needles were too thin to support sculpting. He chose Mount Rushmore, a grander location, partly because it faced southeast and enjoyed maximum exposure to the sun. Borglum said upon seeing Mount Rushmore, "America will march along that skyline."Congress authorized the Mount Rushmore National Memorial Commission on March 3, 1925. President Coolidge insisted that along with Washington, two Republicans and one Democrat be portrayed.


Construction of Mount Rushmore.
Between October 4, 1927, and October 31, 1941, Gutzon Borglum and 400 workers sculpted the colossal 60-foot (18 m) carvings of U.S. presidents George Washington, Thomas Jefferson, Theodore Roosevelt, and Abraham Lincoln to represent the first 150 years of American history. These presidents were selected by Borglum because of their role in preserving the Republic and expanding its territory. The image of Thomas Jefferson was originally intended to appear in the area at Washington's right, but after the work there was begun, the rock was found to be unsuitable, so the work on the Jefferson figure was dynamited, and a new figure was sculpted to Washington's left.
In 1933, the National Park Service took Mount Rushmore under its jurisdiction. Engineer Julian Spotts helped with the project by improving its infrastructure. For example, he had the tram upgraded so that it could reach the top of Mount Rushmore for the ease of workers. By July 4, 1934, Washington's face had been completed and was dedicated. The face of Thomas Jefferson was dedicated in 1936, and the face of Abraham Lincoln was dedicated on September 17, 1937. In 1937, a bill was introduced in Congress to add the head of civil-rights leader Susan B. Anthony, but a rider was passed on an appropriations bill requiring that federal funds be used to finish only those heads that had already been started at that time. In 1939, the face of Theodore Roosevelt was dedicated.
The Sculptor's Studio—a display of unique plaster models and tools related to the sculpting—was built in 1939 under the direction of Borglum. Borglum died from an embolism in March 1941. His son, Lincoln Borglum, continued the project. Originally, it was planned that the figures would be carved from head to waist, but insufficient funding forced the carving to end. Borglum had also planned a massive panel in the shape of the Louisiana Purchase commemorating in eight-foot-tall gilded letters the Declaration of Independence, U.S. Constitution, Louisiana Purchase, and seven other territorial acquisitions from Alaska to Texas to the Panama Canal Zone.

A model at the site depicting Mount Rushmore's intended final design. Insufficient funding forced the carving to end in October 1941.

The entire project cost US$989,992.32. Notably for a project of such size, no workers died during the carving.
On October 15, 1966, Mount Rushmore was listed on the National Register of Historic Places. An essay from Nebraska student William Andrew Burkett, selected as the winner for the college-age group in 1934, was placed on the Entablature on a bronze plate in 1973.In 1991, President George H. W. Bush officially dedicated Mount Rushmore.
In a canyon behind the carved faces is a chamber, cut only 70 feet (21 m) into the rock, containing a vault with sixteen porcelain enamel panels. The panels include the text of the Declaration of Independence and the Constitution, biographies of the four presidents and Borglum, and the history of the U.S. The chamber was created as the entranceway to a planned "Hall of Records"; the vault was installed in 1998.
Ten years of redevelopment work culminated with the completion of extensive visitor facilities and sidewalks in 1998, such as a Visitor Center, the Lincoln Borglum Museum, and the Presidential Trail. Maintenance of the memorial annually requires mountain climbers to monitor and seal cracks. The memorial is not cleaned to remove lichens. It has been cleaned only once. On July 8, 2005, Kärcher GmbH, a German manufacturer of cleaning machines, conducted a free cleanup operation; the washing used pressurized water at over 200 °F (93 °C).




Controversy

                                                                                                Air Force One flying over Mt. Rushmore.

Mount Rushmore is controversial among Native Americans because the United States seized the area from the Lakota tribe after the Great Sioux War of 1876–77. The Treaty of Fort Laramie from 1868 had previously granted the Black Hills to the Lakota in perpetuity. Members of the American Indian Movement led an occupation of the monument in 1971, naming it "Mount Crazy Horse". Among the participants were young activists, grandparents, children and Lakota holy man John Fire Lame Deer, who planted a prayer staff atop the mountain. Lame Deer said the staff formed a symbolic shroud over the presidents' faces "which shall remain dirty until the treaties concerning the Black Hills are fulfilled."
In 2004, the first Native American superintendent of the park was appointed. Gerard Baker has stated that he will open up more "avenues of interpretation", and that the four presidents are "only one avenue and only one focus."
The Crazy Horse Memorial is being constructed elsewhere in the Black Hills to commemorate a famous Native American leader and as a response to Mount Rushmore. It is intended to be larger than Mount Rushmore and has the support of Lakota chiefs; the Crazy Horse Memorial Foundation has rejected offers of federal funds. However, this memorial is likewise the subject of controversy, even within the Native American community.
The Monument also provokes controversy because some allege that underlying it is the theme of racial superiority legitimized by the idea of Manifest Destiny. The mountains were carved with Borglum's choice of four presidents active during the time of the acquisition of Indian land. Gutzon Borglum himself excites controversy because he was an active member of the Ku Klux Klan.
In 2009, author Ivan Eland released Recarving Rushmore: Ranking the Presidents on Peace, Prosperity, and Liberty, a book that advocates a reappraisal of the presidency of three of the four presidents on the monument.




Ecology

The Black Hills opposite Mount Rushmore.
The flora and fauna of Mount Rushmore are similar to those of the rest of the Black Hills region of South Dakota. Birds including the turkey vulture, bald eagle, hawk, and meadowlark fly around Mount Rushmore, occasionally making nesting spots in the ledges of the mountain. Smaller birds, including songbirds, nuthatches, and woodpeckers, inhabit the surrounding pine forests. Terrestrial mammals include the mouse, chipmunk, squirrel, skunk, porcupine, raccoon, beaver, badger, coyote, bighorn sheep, and bobcat. In addition, several species of frogs and snakes inhabit the region. The two brooks in the memorial, the Grizzly Bear and Starling Basin brooks, support fish such as the longnose dace and the brook trout. Some endemic animals are not indigenous to the area; the mountain goats are descended from goats which were a gift from Canada to Custer State Park in 1924 but later escaped.
At lower elevations, coniferous trees, mainly the Ponderosa pine, surround most of the monument, providing shade from the sun. Other trees include the bur oak, the Black Hills spruce, and the cottonwood. Nine species of shrubs live near Mount Rushmore. There is also a wide variety of wildflowers, including especially the snapdragon, sunflower, and violet. Towards higher elevations, plant life becomes sparser. However, only approximately five percent of the plant species found in the Black Hills are indigenous to the region.
Though the area receives about 18 inches (460 mm) of precipitation on average per year, alone it is not enough to support the abundant animal and plant life. Trees and other plants help to control surface runoff. Dikes, seeps, and springs help to dam up water that is flowing downhill, providing watering spots for animals. In addition, stones like sandstone and limestone help to hold groundwater, creating aquifers.
Forest fires occur in the Ponderosa forests surrounding Mount Rushmore around every 27 years. This was determined from fire scars in tree core samples. These help to clean forest debris located on the ground. Large conflagrations are rare, but have occurred in the past.



Geology

Mt. Rushmore, showing the full size of the mountain and the scree of debris from construction.
Mount Rushmore is largely composed of granite. The memorial is carved on the northwest margin of the Harney Peak granite batholith in the Black Hills of South Dakota, so the geologic formations of the heart of the Black Hills region are also evident at Mount Rushmore. The batholith magma intruded into the pre-existing mica schist rocks during the Precambrian period about 1.6 billion years ago. Very coarse grained pegmatite is associated with the granite of Harney Peak. The light-colored streaks in the presidents' foreheads are due to these dikes.


Model of Mount Rushmore in Legoland Windsor.
The Black Hills granites were exposed to erosion during the late Precambrian, but were buried by sandstones and other sediments during the Cambrian Period. The area remained buried throughout the Paleozoic Era, but was exposed again to erosion during the tectonic uplift about 70 million years ago. The Black Hills area was uplifted as an elongated geologic dome. The subsequent natural erosion of this mountain range allowed the carvings by stripping the granite of the overlying sediments and the softer adjacent schists. The contact between the granite and darker schist is viewable just below the sculpture of Washington.
Borglum selected Mount Rushmore as the site for several reasons. The rock of the mountain is composed of smooth, fine-grained granite. The durable granite erodes only 1 inch (25 mm) every 10,000 years, indicating that it was sturdy enough to support sculpting. In addition, it was the tallest mountain in the region, looming to a height of 5,725 feet (1,745 m) above sea level. Because the mountain faces the southeast, the workers also had the advantage of sunlight for most of the day.


Tourism

The entrance to the site.
Tourism is South Dakota's second-largest industry, and Mount Rushmore is its top tourist attraction. In 2004, over two million visitors traveled to the memorial. The site is also home to the final concerts of Rushmore Music Camp and attracts many visitors over the week of the Sturgis Motorcycle Rally.
Source:wikipedia

Construction of Mount Rushmore

The construction of Mount Rushmore National Memorial took about 14 years, from 1927 to 1941.

Designing the monument

Doane Robinson of the South Dakota Historical Society wanted a monument to be built in South Dakota in order to help the economy of the state by attracting tourism. In 1923, he proposed that this monument should be built from the granite cliffs in the Black Hills of South Dakota. Senator Peter Norbeck of South Dakota approved of the proposal, and federal funds helped the project. Robinson asked architect and sculptor Gutzon Borglum to sculpt and design the monument. Borglum decided to use Mount Rushmore for the sculpture, since it appeared the easiest of the cliffs to work on.
Gutzon Borglum, having decided on the location of the sculpture, decided to make this monument of four Presidents of the United States. He chose the two most famous Presidents in history, George Washington and Abraham Lincoln. He chose Thomas Jefferson because Jefferson nearly doubled the size of the United States in the 1803 Louisiana Purchase (which included the land that became South Dakota). The last President Borglum chose was Theodore Roosevelt, suggested by President Calvin Coolidge (who insisted there be two Republicans and only one Democrat represented.) because of Theodore Roosevelt's introduction of the National Park Service.
Borglum's original design was a sculpture of the four presidents to their waists, but time and money only provided for their heads.



Construction

Workers used harnesses attached to steel cables while sculpting.

A few hundred workers, who were usually miners, sculptors, or rock climbers, used dynamite, jackhammering, and chiseling to sculpt the model from the mountain. A stairway was constructed to the top of the mountain first and ropes fixed. Workers were supported by harnesses attached to the ropes.
The irises of the eyes were sculpted as holes. A cube of granite was left in each to represent the reflection highlight thereby making the appearance of the eyes more realistic.
Construction began on August 10, 1927.




George Washington


                                              Construction on the George Washington portrait at Mount Rushmore, c. 1932.

George Washington's head was started first. Due to the economic instability of the United States caused by the Great Depression, it was completed in seven years, and dedicated to the public on Independence Day 1934. A large American flag was placed over Washington's head before it was revealed, and this became a tradition for each of the Presidents' heads.



Thomas Jefferson
Thomas Jefferson's head was started next, left of Washington. Before the head was complete, Borglum ordered that it be blasted off due to poor rock quality. Jefferson's head was started again to the right of Washington. Jefferson's head was dedicated in 1936.



Abraham Lincoln
Abraham Lincoln's head was more of a challenge because of his beard, but his head was completed on the far right of the cliff, dedicated on September 17, 1937, the 150th anniversary of the signing of the Constitution of the United States in 1787.




Theodore Roosevelt
While Theodore Roosevelt's head was being constructed, accommodations for tourists were being built, including plumbing, lighting, and a visitor center. Not finding suitable rock, the sculptors cut farther back into the mountain, causing concerns about how far they were cutting. On July 2, 1939, Roosevelt's head was dedicated.



Hall of Records
Due to unforeseen vulnerabilities in the granite, Lincoln and Jefferson were moved from the locations in Borglum's original design. Lincoln was relocated to the spot that Borglum had planned to include an 80 by 100 foot inscription in the shape of the Louisiana Purchase.
To replace the inscription, Borglum conceived another grand addition to the monument of similar proportions: the Hall of Records. The Hall of Records was to include a grand entrance to an 80 by 100 foot vault carved directly into the granite face of the small canyon behind Lincoln’s head. Borglum envisioned 800 granite steps leading from his studio to the entrance of the Hall.
In 1938 Borglum and his crew began to carve this grand hall, where he envisioned the original Declaration of Independence and United States Constitution should eventually be stored. But a combination of unexpectedly hard granite, looming war in Europe, and lack of funding conspired against Borglum’s last dream, though his plans became more elaborate as his team rushed to complete this work. They reached 70 feet into the granite by the time Borglum unexpectedly died in March 1941. The monument was deemed complete and all work shut down on October 31 of the same year. Though Borglum’s children tried over the years to renew interest in their father’s last dream, it was not until 1998 that the National Park System, together with the Borglum Family, put “finishing touches” on the Hall of Records. A titanium vault was installed in the granite floor of the unfinished hall, and filled with sixteen porcelain enamel panels that include the United States Constitution and other important historical documents. The Hall of Records entrance can be seen from west-facing aerial photographs of the monument from Bing Maps.




Present day

The granite remains from the construction of Mount Rushmore are still visible below the heads of the Presidents.
Every year more than 2 million people travel to South Dakota to marvel at Mt. Rushmore. The Lincoln Borglum Museum is located by the memorial. One of the best locations for viewing Mt. Rushmore is located above the museum at Grandview Terrace. The Presidential Trail, a walking trail and boardwalk, starts at Grandview Terrace and travels through the forests to the Sculptor's Studio, providing up-close views of the memorial. The Sculptor's studio built by Gutzon Borglum features discussion about the construction of the monument and the tools used by workers.
Source:

Nikola Tesla

Nikola Tesla (Serbian: Никола Тесла, born 10 July 1856 in Smiljan, Croatia - died 7 January 1943 in New York) was an inventor, mechanical engineer, and electrical engineer. He was one of the most important contributors to the birth of commercial electricity, and is best known for his many revolutionary developments in the field of electromagnetism in the late 19th and early 20th centuries. Tesla's patents and theoretical work formed the basis of modern alternating current (AC) electric power systems, including the polyphase system of electrical distribution and the AC motor, with which he helped usher in the Second Industrial Revolution.

Born an ethnic Serb in the village of Smiljan, Croatian Military Frontier in Austrian Empire (today's Croatia), he was a subject of the Austrian Empire by birth and later became an American citizen. After his demonstration of wireless communication through radio in 1894 and after being the victor in the "War of Currents", he was widely respected as one of the greatest electrical engineers who worked in America. Much of his early work pioneered modern electrical engineering and many of his discoveries were of groundbreaking importance. During this period, in the United States, Tesla's fame rivaled that of any other inventor or scientist in history or popular culture,[3] but because of his eccentric personality and his seemingly unbelievable and sometimes bizarre claims about possible scientific and technological developments, Tesla was ultimately ostracized and regarded as a mad scientist. Tesla never put much focus on his finances and died impoverished at the age of 86.

The International System of Units unit measuring magnetic field B (also referred to as the magnetic flux density and magnetic induction), the tesla, was named in his honor (at the Conférence Générale des Poids et Mesures, Paris, 1960), as well as the Tesla effect of wireless energy transfer to wireless powered electronic devices (which Tesla demonstrated on a low scale with incandescent light bulbs as early as 1893 and aspired to use for the intercontinental transmission of industrial power levels in his unfinished Wardenclyffe Tower project).

Aside from his work on electromagnetism and electromechanical engineering, Tesla contributed in varying degrees to the establishment of robotics, remote control, radar, and computer science, and to the expansion of ballistics, nuclear physics, and theoretical physics. A few of his achievements have been used, with some controversy, to support various pseudosciences, UFO theories, and early New Age occultism.

Early years

Nikola Tesla's birth house and statue in the village of Smiljan, Croatia

c.1879 at age 23

Three-phase rotating magnetic field

Tesla was born to Serbian parents in the village of Smiljan, Austrian Empire near the town of Gospić, in the territory of modern-day Croatia. His baptismal certificate reports that he was born on 28 June (N.S. 10 July), 1856, to Father Milutin Tesla, a priest in the Serbian Orthodox Church, Metropolitanate of Sremski Karlovci and Đuka Mandić. His paternal origin is thought to be either of one of the local Serb clans in the Tara valley or from the Herzegovinian noble Pavle Orlović. His mother, Đuka, daughter of a Serbian Orthodox Church priest, came from a family domiciled in Lika and Banija, but with deeper origins to Kosovo. She was talented in making home craft tools and memorized many Serbian epic poems, but never learned to read.

Nikola was the fourth of five children, having one older brother (Dane, who was killed in a horse-riding accident when Nikola was five) and three sisters (Milka, Angelina and Marica).3 His family moved to Gospić in 1862. Tesla attended school at Higher Real Gymnasium in Karlovac. He finished a four-year term in the span of three years.

Tesla then studied electrical engineering at the Austrian Polytechnic in Graz (1875). While there, he studied the uses of alternating current. Some sources say he received Baccalaureate degrees from the university at Graz. However, the university claims that he did not receive a degree and did not continue beyond the first semester of his third year, during which he stopped attending lectures. In December 1878 he left Graz and broke all relations with his family. His friends thought that he had drowned in Mura. He went to Maribor, (today's Slovenia), where he was first employed as an assistant engineer for a year. He suffered a nervous breakdown during this time. Tesla was later persuaded by his father to attend the Charles-Ferdinand University in Prague, which he attended for the summer term of 1880. Here, he was influenced by Ernst Mach. However, after his father died, he left the university, having completed only one term.

Tesla engaged in reading many works, memorizing complete books, supposedly having a photographic memory. Tesla related in his autobiography that he experienced detailed moments of inspiration. During his early life, Tesla was stricken with illness time and time again. He suffered a peculiar affliction in which blinding flashes of light would appear before his eyes, often accompanied by hallucinations. Much of the time the visions were linked to a word or idea he might have come across; just by hearing the name of an item, he would involuntarily envision it in realistic detail. Modern-day synesthetes report similar symptoms. Tesla would visualise an invention in his brain with extreme precision, including all dimensions, before moving to the construction stage; a technique sometimes known as picture thinking. He typically did not make drawings by hand, instead just conceiving all ideas with his mind. Tesla also often had flashbacks to events that had happened previously in his life; these began during his childhood.

In 1880, he moved to Budapest to work under Tivadar Puskás in a telegraph company, the National Telephone Company. There, he met Nebojša Petrović, a young, Serbian inventor who lived in Austria. Although their encounter was brief, they did work on a project together using twin turbines to create continual power. On the opening of the telephone exchange in Budapest, 1881, Tesla became the chief electrician to the company, and was later engineer for the country's first telephone system. He also developed a device that, according to some, was a telephone repeater or amplifier, but according to others could have been the first loudspeaker.

Drawing from U.S. Patent 381968, illustrating principle of alternating current motor invention

United States and France

In 1882 he moved to Paris, to work as an engineer for the Continental Edison Company, designing improvements to electric equipment brought overseas from Edison's ideas. According to his autobiography, in the same year he conceived the induction motor and began developing various devices that use rotating magnetic fields for which he received patents in 1888.

Soon thereafter, Tesla was awakened from a dream in which his mother had died, "And I knew that this was so".[24] After her death, Tesla fell ill. He spent two to three weeks recuperating in Gospić and the village of Tomingaj near Gračac, his mother's birthplace.

On 6 June 1884, Tesla first arrived in the United States, in New York City with little besides a letter of recommendation from Charles Batchelor, a former employer. In the letter of recommendation to Thomas Edison, Batchelor wrote, "I know two great men and you are one of them; the other is this young man." Edison hired Tesla to work for his Edison Machine Works. Tesla's work for Edison began with simple electrical engineering and quickly progressed to solving some of the company's most difficult problems. Tesla was even offered the task of completely redesigning the Edison company's direct current generators.

Tesla claims he was offered US$50,000 (~ US$1.1 million in 2007, adjusted for inflation) if he redesigned Edison's inefficient motor and generators, making an improvement in both service and economy.:54–57 In 1885 when Tesla inquired about the payment for his work, Edison replied, "Tesla, you don't understand our American humor," thus breaking his word. Earning US$18 per week, Tesla would have had to work for 53 years to earn the amount he was promised. The offer was equal to the initial capital of the company. Tesla immediately resigned when he was refused a raise to US$25 per week.

Tesla, in need of work, eventually found himself digging ditches for a short period of time for the Edison company. He used this time to focus on his AC polyphase system.

Electromechanical devices and principles developed by Nikola Tesla:

Various devices that use rotating magnetic fields (1882)

The Induction motor, rotary transformers, and "high" frequency alternators

The Tesla coil,his magnifying transmitter, and other means for increasing the intensity of electrical oscillations (including condenser discharge transformations and the Tesla oscillators)

Alternating current long-distance electrical transmission system (1888) and other methods and devices for power transmission

Systems for wireless communication (prior art for the invention of radio) and radio frequency oscillators

Robotics and the electronic logic gate

Electrotherapy Tesla currents

Wireless transfer of electricity and the Tesla effec

Tesla impedance phenonomena

Tesla electro-static field

Tesla principle

Bifilar coil

Telegeodynamics

Tesla insulation

Tesla impulses

Tesla frequencies

Tesla discharge

Forms of commutators and methods of regulating third brushes

Tesla turbines (eg., bladeless turbines) for water, steam and gas and the Tesla pumps

Tesla igniter

Corona discharge ozone generator

Tesla compressor

X-rays Tubes using the Bremsstrahlung process

Devices for ionized gases and "Hot Saint Elmo's Fire".

Devices for high field emission

Devices for charged particle beams

Phantom streaming devices

Arc light systems

Methods for providing extremely low level of resistance to the passage of electrical current (predecessor to superconductivity)

Voltage multiplication circuitry

Devices for high voltage discharges

Devices for lightning protection

VTOL aircraft

Dynamic theory of gravity

Concepts for electric vehicles

Polyphase systems

Middle years

In 1886, Tesla formed his own company, Tesla Electric Light & Manufacturing. The initial financial investors disagreed with Tesla on his plan for an alternating current motor and eventually relieved him of his duties at the company. Tesla worked in New York as a laborer from 1886 to 1887 to feed himself and raise capital for his next project. In 1887, he constructed the initial brushless alternating current induction motor, which he demonstrated to the American Institute of Electrical Engineers (now IEEE) in 1888. In the same year, he developed the principles of his Tesla coil, and began working with George Westinghouse at Westinghouse Electric & Manufacturing Company's Pittsburgh labs. Westinghouse listened to his ideas for polyphase systems which would allow transmission of alternating current electricity over long distances.

In April 1887, Tesla began investigating what would later be called X-rays using his own single terminal vacuum tubes (similar to his patent #514,170). This device differed from other early X-ray tubes in that it had no target electrode. The modern term for the phenomenon produced by this device is bremsstrahlung (or braking radiation). We now know that this device operated by emitting electrons from the single electrode through a combination of field electron emission and thermionic emission. Once liberated, electrons are strongly repelled by the high electric field near the electrode during negative voltage peaks from the oscillating HV output of the Tesla Coil, generating X rays as they collide with the glass envelope. He also used Geissler tubes. By 1892, Tesla became aware of the skin damage that Wilhelm Röntgen later identified as an effect of X rays.

In the early research, Tesla devised several experimental setups to produce X-rays. Tesla held that, with his circuits, the "instrument will [... enable one to] generate Roentgen rays of much greater power than obtainable with ordinary apparatus".

He also commented on the hazards of working with his circuit and single-node X-ray-producing devices. Of his many notes in the early investigation of this phenomenon, he attributed the skin damage to various causes. He believed early on that damage to the skin was not caused by the Roentgen rays, but the ozone generated in contact with the skin, and to a lesser extent, nitrous acid. Tesla incorrectly held that x-rays were longitudinal waves, such as those produced in waves in plasma. There are known examples of this and these plasma waves can occur in the situation of force-free magnetic fields. His hypotheses and experiments were confirmed by others.

Tesla continued research in the field. He performed several experiments prior to Roentgen's discovery (including photographing the bones of his hand; later, he sent these images to Roentgen) but did not make his findings widely known; much of his research was lost in the 5th Avenue laboratory fire of March 1895.

The Tesla generator was developed by Tesla in 1895, in conjunction with his developments concerning the liquefaction of air. Tesla knew, from Lord Kelvin's discoveries, that more heat is absorbed by liquefied air when it is re-gasified and used to drive something, than is required by theory; in other words, that the liquefaction process is somewhat anomalous or 'over unity'. Just prior to Tesla's completion of his work and the filing of a patent application, Tesla's laboratory burned down, destroying all his equipment, models and inventions. Immediately after the fire, Linde, in Germany, filed a patent application for the same process.

A "world system" for "the transmission of electrical energy without wires" that depends upon the electrical conductivity of the earth was proposed, in which transmission in various natural media with current that passes between the two points are used to power devices. In a practical wireless energy transmission system using this principle, a high-power ultraviolet beam might be used to form a vertical ionized channel in the air directly above the transmitter-receiver stations. The same concept is used in virtual lightning rods, the electrolaser electroshock weapon, and has been proposed for disabling vehicles.[

Tesla demonstrated "the transmission of electrical energy without wires" as early as 1891. The Tesla effect (named in honor of Tesla) is a term for an application of this type of electrical conduction (that is, the movement of energy through space and matter, not just the production of voltage across a conductor)

Wireless transmission of power and energy demonstration during his high frequency and potential lecture of 1891

American citizenship

On 30 July 1891, he became a naturalized citizen of the United States at the age of 35. Tesla established his 35 South Fifth Avenue laboratory in New York in the same year. Later, Tesla established his Houston Street laboratory in New York at 46 E. Houston Street. There, at one point while conducting mechanical resonance experiments with electro-mechanical oscillators, he generated a resonance in several surrounding buildings but, because of the frequencies involved, not his own building, causing complaints to the police. As the speed grew, he hit the resonant frequency of his own building and, belatedly realizing the danger, was forced to apply a sledgehammer to terminate the experiment, just as the police arrived. He also lit electric lamps wirelessly at both of the New York locations, providing evidence for the potential of wireless power transmission.

Some of Tesla's closest friends were artists. He befriended Century Magazine editor Robert Underwood Johnson, who adapted several Serbian poems of Jovan Jovanović Zmaj (which Tesla translated). Also during this time, Tesla was influenced by the Vedic philosophy (i.e., Hinduism) teachings of the Swami Vivekananda; so much so that, after his exposure to Hindu-Vedic thought, Tesla started using Sanskrit words to name some of his fundamental concepts regarding matter and energy.

When Tesla was 36 years old, the first patents concerning the polyphase power system were granted. He continued research of the system and rotating magnetic field principles. Tesla served, from 1892 to 1894, as the vice president of the American Institute of Electrical Engineers, the forerunner (along with the Institute of Radio Engineers) of the modern-day IEEE. From 1893 to 1895, he investigated high frequency alternating currents. He generated AC of one million volts using a conical Tesla coil and investigated the skin effect in conductors, designed tuned circuits, invented a machine for inducing sleep, cordless gas discharge lamps, and transmitted electromagnetic energy without wires, building the first radio transmitter. In St. Louis, Missouri, Tesla made a demonstration related to radio communication in 1893. Addressing the Franklin Institute in Philadelphia, Pennsylvania and the National Electric Light Association, he described and demonstrated in detail its principles. Tesla's demonstrations were written about widely through various media outlets. Tesla also investigated harvesting energy that is present throughout space. He believed that it was merely a question of time when men would succeed in attaching their machinery to the very wheelwork of nature, stating:

Nikola Tesla's AC dynamo used to generate AC which is used to transport electricity across great distances. It is contained in U.S. Patent 390,721.

Ere many generations pass, our machinery will be driven by a power obtainable at any point of the universe.

At the 1893 World's Fair, the World's Columbian Exposition in Chicago, an international exposition was held which, for the first time, devoted a building to electrical exhibits. It was a historic event as Tesla and George Westinghouse introduced visitors to AC power by using it to illuminate the Exposition. On display were Tesla's fluorescent lamps and single node bulbs. An observer noted:

Within the room was suspended two hard-rubber plates covered with tin foil. These were about fifteen feet apart, and served as terminals of the wires leading from the transformers. When the current was turned on, the lamps or tubes, which had no wires connected to them, but lay on a table between the suspended plates, or which might be held in the hand in almost any part of the room, were made luminous. These were the same experiments and the same apparatus shown by Tesla in London about two years previous, "where they produced so much wonder and astonishment.".

Tesla also explained the principles of the rotating magnetic field and induction motor by demonstrating how to make an egg made of copper stand on end in his demonstration of the device he constructed known as the "Egg of Columbus".

Edison

Also in the late 1880s, Tesla and Edison became adversaries in part because of Edison's promotion of direct current (DC) for electric power distribution over the more efficient alternating current advocated by Tesla and Westinghouse. Until Tesla invented the induction motor, AC's advantages for long distance high voltage transmission were counterbalanced by the inability to operate motors on AC. As a result of the "War of Currents", Edison and Westinghouse went nearly bankrupt, so in 1897, Tesla released Westinghouse from contract, providing Westinghouse a break from Tesla's patent royalties. Also in 1897, Tesla researched radiation, which led to setting up the basic formulation of cosmic rays.

When Tesla was 41 years old, he filed the first radio patent (U.S. Patent 645,576). A year later, he demonstrated a radio-controlled boat to the US military, believing that the military would want things such as radio-controlled torpedoes. Tesla claimed to have developed the "Art of Telautomatics", a form of robotics, as well as the technology of remote control. In 1898, he demonstrated a radio-controlled boat to the public during an electrical exhibition at Madison Square Garden. Tesla called his boat a "teleautomaton". Radio remote control remained a novelty until the 1960s. In the same year, Tesla devised an "electric igniter" or spark plug for Internal combustion gasoline engines. He gained U.S. Patent 609,250, "Electrical Igniter for Gas Engines", on this mechanical ignition system. Tesla lived in the former Gerlach Hotel, renamed The Radio Wave building, at 49 W 27th St. (between Broadway and Sixth Avenue), Lower Manhattan, before the end of the century where he conducted the radio wave experiments. A commemorative plaque was placed on the building in 1977 to honor his work.

Colorado Springs

Publicity picture of a participant sitting in his laboratory in Colorado Springs with his "Magnifying transmitter" generating millions of volts. The arcs are about 7 meters (23 ft) long. (Tesla's notes identify this as a multiple exposure photograph.)

An experiment in Colorado Springs. This bank of lights is receiving power from a distant transmitter

A Colorado Springs experiment: here a grounded tuned coil in resonance with a distant transmitter illuminates a light near the bottom of the picture.

In 1899, Tesla decided to move and began research in Colorado Springs, Colorado in a lab located near Foote Ave. and Kiowa St., where he would have room for his high-voltage, high-frequency experiments. Upon his arrival he told reporters that he was conducting wireless telegraphy experiments transmitting signals from Pikes Peak to Paris. Tesla's diary contains explanations of his experiments concerning the ionosphere and the ground's telluric currents via transverse waves and longitudinal waves. At his lab, Tesla proved that the earth was a conductor, and he produced artificial lightning (with discharges consisting of millions of volts, and up to 135 feet long).Tesla also investigated atmospheric electricity, observing lightning signals via his receivers. Reproductions of Tesla's receivers and coherer circuits show an unpredicted level of complexity (e.g., distributed high-Q helical resonators, radio frequency feedback, crude heterodyne effects, and regeneration techniques). Tesla stated that he observed stationary waves during this time.

Tesla researched ways to transmit power and energy wirelessly over long distances (via transverse waves, to a lesser extent, and, more readily, longitudinal waves). He transmitted extremely low frequencies through the ground as well as between the Earth's surface and the Kennelly–Heaviside layer. He received patents on wireless transceivers that developed standing waves by this method. In his experiments, he made mathematical calculations and computations based on his experiments and discovered that the resonant frequency of the Earth was approximately 8 hertz (Hz). In the 1950s, researchers confirmed that the resonant frequency of the Earth's ionospheric cavity was in this range (later named the Schumann resonance).

In Colorado, Tesla carried out various long distance power transmission experiments. Tesla effect is the application of a type of electrical conduction (that is, the movement of energy through space and matter; not just the production of voltage across a conductor). Through longitudinal waves, Tesla transferred energy to receiving devices. He sent electrostatic forces through natural media across a conductor situated in the changing magnetic flux and transferred power to a conducting receiving device (such as Tesla's wireless bulbs).

In the Colorado Springs lab, Tesla observed unusual signals that he later thought may have been evidence of extraterrestrial radio communications coming from Venus or Mars. He noticed repetitive signals from his receiver which were substantially different from the signals he had noted from storms and earth noise. Specifically, he later recalled that the signals appeared in groups of one, two, three, and four clicks together. Tesla had mentioned that he thought his inventions could be used to talk with other planets. There have even been claims that he invented a "Teslascope" for just such a purpose. It is debatable what type of signals Tesla received or whether he picked up anything at all. Research has suggested that Tesla may have had a misunderstanding of the new technology he was working with, or that the signals Tesla observed may have simply been an observation of a non-terrestrial natural radio source such as the Jovian plasma torus signals.

Tesla left Colorado Springs on 7 January 1900. The lab was torn down and its contents sold to pay debts. The Colorado experiments prepared Tesla for his next project, the establishment of a wireless power transmission facility that would be known as Wardenclyffe. Tesla was granted U.S. Patent 685,012 for the means of increasing the intensity of electrical oscillations. The United States Patent Office classification system currently assigns this patent to the primary Class 178/43 ("telegraphy/space induction"), although the other applicable classes include 505/825 ("low temperature superconductivity-related apparatus").

Later years

In 1900, with US$150,000 (51 % from J. Pierpont Morgan), Tesla began planning the Wardenclyffe Tower facility. In June 1902, Tesla's lab operations were moved to Wardenclyffe from Houston Street. The tower was dismantled for scrap during World War I. Newspapers of the time labeled Wardenclyffe "Tesla's million-dollar folly". In 1904, the US Patent Office reversed its decision and awarded Guglielmo Marconi the patent for radio, and Tesla began his fight to re-acquire the radio patent. On his 50th birthday in 1906, Tesla demonstrated his 200 hp (150 kW) 16,000 rpm bladeless turbine. During 1910–1911 at the Waterside Power Station in New York, several of his bladeless turbine engines were tested at 100–5000 hp.

Since the Nobel Prize in Physics was awarded to Marconi for radio in 1909, Thomas Edison and Tesla were mentioned as potential laureates to share the Nobel Prize of 1915 in a press dispatch, leading to one of several Nobel Prize controversies. Some sources have claimed that because of their animosity toward each other neither was given the award, despite their scientific contributions, and that each sought to minimize the other's achievements and right to win the award, that both refused to ever accept the award if the other received it first, and that both rejected any possibility of sharing it.

In the following events after the rumors, neither Tesla nor Edison won the prize (although Edison did receive one of 38 possible bids in 1915, and Tesla did receive one bid out of 38 in 1937). Earlier, Tesla alone was rumored to have been nominated for the Nobel Prize of 1912. The rumored nomination was primarily for his experiments with tuned circuits using high-voltage high-frequency resonant transformers.

In 1915, Tesla filed a lawsuit against Marconi attempting, unsuccessfully, to obtain a court injunction against Marconi's claims. After Wardenclyffe, Tesla built the Telefunken Wireless Station in Sayville, Long Island. Some of what he wanted to achieve at Wardenclyffe was accomplished with the Telefunken Wireless. In 1917, the facility was seized and torn down by the Marines, because it was suspected that it could be used by German spies.

The Wardenclyffe Tower facility

Before World War I, Tesla looked overseas for investors to fund his research. When the war started, Tesla lost the funding he was receiving from his patents in European countries. After the war ended, Tesla made predictions regarding the relevant issues of the post-World War I environment, in a printed article (20 December 1914). Tesla believed that the League of Nations was not a remedy for the times and issues. Tesla started to exhibit pronounced symptoms of obsessive-compulsive disorder in the years following. He became obsessed with the number three; he often felt compelled to walk around a block three times before entering a building, demanded a stack of three folded cloth napkins beside his plate at every meal, etc. The nature of OCD was little understood at the time and no treatments were available, so his symptoms were considered by some to be evidence of partial insanity, and this undoubtedly hurt what was left of his reputation.

At this time, he was staying at The Waldorf-Astoria Hotel, renting in an arrangement for deferred payments. Eventually, the Wardenclyffe deed was turned over to George Boldt, proprietor of the Waldorf-Astoria, to pay a US$20,000 debt. In 1917, around the time that the Wardenclyffe Tower was demolished by Boldt to make the land a more viable real estate asset, Tesla received AIEE's highest honor, the Edison Medal.

Tesla, in August 1917, first established principles regarding frequency and power level for the first primitive radar units.

In 1934, Émile Girardeau, working with the first French radar systems, stated he was building them "according to the principles stated by Tesla". By the 1920s, Tesla was reportedly negotiating with the United Kingdom government about a ray system. Tesla had also stated that efforts had been made to steal the so called "death ray". It is suggested that the removal of the Chamberlain government ended negotiations.

On Tesla's 75th birthday in 1931, Time magazine put him on its cover. The cover caption noted his contribution to electrical power generation. Tesla received his last patent in 1928 for an apparatus for aerial transportation which was the first instance of VTOL aircraft. By the end of 1931, Tesla released "On Future Motive Power" which covered an ocean thermal energy conversion system. In 1934, Tesla wrote to consul Janković of his homeland. The letter contained a message of gratitude to Mihajlo Pupin who had initiated a donation scheme by which American companies could support Tesla. Tesla refused the assistance, choosing instead to live on a modest pension received from Yugoslavia, and to continue his research.

In 1936, Tesla wrote in a telegram to Vladko Maček: "I'm equally proud of my Serbian origin and my Croatian homeland. Long live all Yugoslavs."

Field theories

When he was 81, Tesla stated he had completed a "dynamic theory of gravity". He stated that it was "worked out in all details" and that he hoped to soon give it to the world. The theory was never published.

The bulk of the theory was developed between 1892 and 1894, during the period that he was conducting experiments with high frequency and high potential electromagnetism and patenting devices for their use.

Reminiscent of Mach's principle, Tesla stated in 1925 that:

Nikola Tesla, with Ruđer Bošković's book Theoria Philosophiae Naturalis, sits in front of the spiral coil of his high-frequency transformer at East Houston Street, New York.

There is no thing endowed with life—from man, who is enslaving the elements, to the nimblest creature—in all this world that does not sway in its turn. Whenever action is born from force, though it be infinitesimal, the cosmic balance is upset and the universal motion results.

Tesla was critical of Einstein's relativity work, calling it:

...[a] magnificent mathematical garb which fascinates, dazzles and makes people blind to the underlying errors. The theory is like a beggar clothed in purple whom ignorant people take for a king ... its exponents are brilliant men but they are metaphysicists rather than scientists ...

Tesla also argued:

I hold that space cannot be curved, for the simple reason that it can have no properties. It might as well be said that God has properties. He has not, but only attributes and these are of our own making. Of properties we can only speak when dealing with matter filling the space. To say that in the presence of large bodies space becomes curved is equivalent to stating that something can act upon nothing. I, for one, refuse to subscribe to such a view.

Tesla also believed that much of Albert Einstein's relativity theory had already been proposed by Ruđer Bošković, stating in an unpublished interview:

...the relativity theory, by the way, is much older than its present proponents. It was advanced over 200 years ago by my illustrious countryman Ruđer Bošković, the great philosopher, who, not withstanding other and multifold obligations, wrote a thousand volumes of excellent literature on a vast variety of subjects. Bošković dealt with relativity, including the so-called time-space continuum ...'.

Directed-energy weapon

Later in life, Tesla made remarkable claims concerning a "teleforce" weapon. The press called it a "peace ray" or death ray. In total, the components and methods included:

An apparatus for producing manifestations of energy in free air instead of in a high vacuum as in the past. This, according to Tesla in 1934, was accomplished.

A mechanism for generating tremendous electrical force. This, according to Tesla, was also accomplished.

A means of intensifying and amplifying the force developed by the second mechanism.

A new method for producing a tremendous electrical repelling force. This would be the projector, or gun, of the invention.

Tesla worked on plans for a directed-energy weapon from the early 1900s until his death. In 1937, Tesla composed a treatise entitled "The Art of Projecting Concentrated Non-dispersive Energy through the Natural Media" concerning charged particle beams. Tesla published the document in an attempt to expound on the technical description of a "superweapon that would put an end to all war". This treatise of the particle beam is currently in the Nikola Tesla Museum archive in Belgrade. It described an open ended vacuum tube with a gas jet seal that allowed particles to exit, a method of charging particles to millions of volts, and a method of creating and directing nondispersive particle streams (through electrostatic repulsion).

His records indicate that it was based on a narrow stream of atomic clusters of liquid mercury or tungsten accelerated via high voltage (by means akin to his magnifying transformer). Tesla gave the following description concerning the particle gun's operation:

[The nozzle would] send concentrated beams of particles through the free air, of such tremendous energy that they will bring down a fleet of 10,000 enemy airplanes at a distance of 200 miles from a defending nation's border and will cause armies to drop dead in their tracks.

The weapon could be used against ground based infantry or for antiaircraft purposes. Tesla tried to interest the US War Department in the device. He also offered this invention to European countries.None of the governments purchased a contract to build the device. He was unable to act on his plans.

Theoretical inventions

Another of Tesla's theorized inventions is commonly referred to as Tesla's Flying Machine, which appears to resemble an ion-propelled aircraft. Tesla claimed that one of his life goals was to create a flying machine that would run without the use of an airplane engine, wings, ailerons, propellers, or an onboard fuel source. Initially, Tesla pondered about the idea of a flying craft that would fly using an electric motor powered by grounded base stations. As time progressed, Tesla suggested that perhaps such an aircraft could be run entirely electro-mechanically. The theorized appearance would typically take the form of a cigar or saucer..

Personal life

Tesla's father Milutin Tesla

Tesla was fluent in many languages. Along with Serbian, he spoke seven other languages: Czech, English, French, German, Hungarian, Italian, and Latin.

Tesla may have suffered from obsessive-compulsive disorder, and had many unusual quirks and phobias. He did things in threes, and was adamant about staying in a hotel room with a number divisible by three. Tesla was physically revolted by jewelry, notably pearl earrings. He was fastidious about cleanliness and hygiene, and was by all accounts mysophobic.

Tesla was obsessed with pigeons, ordering special seeds for the pigeons he fed in Central Park and even bringing some into his hotel room with him. Tesla was an animal-lover, often reflecting contentedly about a childhood cat, "The Magnificent Mačak." Tesla never married. He was celibate and claimed that his chastity was very helpful to his scientific abilities. Nonetheless there have been numerous accounts of women vying for Tesla's affection, even some madly in love with him. Tesla, though polite, behaved rather ambivalently to these women in the romantic sense.

Tesla was prone to alienating himself and was generally soft-spoken. However, when he did engage in a social life, many people spoke very positively and admiringly of him. Robert Underwood Johnson described him as attaining a "distinguished sweetness, sincerity, modesty, refinement, generosity, and force." His loyal secretary, Dorothy Skerrit, wrote: "his genial smile and nobility of bearing always denoted the gentlemanly characteristics that were so ingrained in his soul." Tesla's friend Hawthorne wrote that "seldom did one meet a scientist or engineer who was also a poet, a philosopher, an appreciator of fine music, a linguist, and a connoisseur of food and drink."

Nevertheless, Tesla displayed the occasional cruel streak; he openly expressed his disgust for overweight people, once firing a secretary because of her weight.:110 He was quick to criticize others' clothing as well, on several occasions demanding a subordinate to go home and change her dress.

Tesla was widely known for his great showmanship, presenting his innovations and demonstrations to the public as an artform, almost like a magician. This seems to conflict with his observed reclusiveness; Tesla was a complicated figure. He refused to hold conventions without his Tesla coil blasting electricity throughout the room, despite the audience often being terrified, though he assured them everything was perfectly safe.

Mark Twain in Tesla's lab, early 1894

In middle age, Tesla became close friends with Mark Twain. They spent a lot of time together in his lab and elsewhere.

Tesla remained bitter in the aftermath of his dispute with Edison. The day after Edison died the New York Times contained extensive coverage of Edison's life, with the only negative opinion coming from Tesla, who was quoted as saying:

He had no hobby, cared for no sort of amusement of any kind and lived in utter disregard of the most elementary rules of hygiene ... His method was inefficient in the extreme, for an immense ground had to be covered to get anything at all unless blind chance intervened and, at first, I was almost a sorry witness of his doings, knowing that just a little theory and calculation would have saved him 90 percent of the labor. But he had a veritable contempt for book learning and mathematical knowledge, trusting himself entirely to his inventor's instinct and practical American sense.

Shortly before he died, Edison said that his biggest mistake had been in trying to develop direct current, rather than the superior alternating current system that Tesla had put within his grasp.:19

Tesla was good friends with Robert Underwood Johnson. He had amicable relations with Francis Marion Crawford, Stanford White, Fritz Lowenstein, George Scherff, and Kenneth Swezey. He ripped up a Westinghouse contract that would have made him the world's first billionaire, in part because of the implications it would have on his future vision of free power, and in part because it would run Westinghouse out of business, and Tesla had no desire to deal with the creditors.

Tesla lived the last ten years of his life in a two-room suite on the 33rd floor of the Hotel New Yorker, room 3327. There, near the end of his life, Tesla showed signs of encroaching mental illness, claiming to be visited by a specific white pigeon daily. Several biographers note that Tesla viewed the death of the pigeon as a "final blow" to himself and his work.

Tesla believed that war could not be avoided until the cause for its recurrence was removed, but was opposed to wars in general. He sought to reduce distance, such as in communication for better understanding, transportation, and transmission of energy, as a means to ensure friendly international relations.

Like many of his era, Tesla, a life-long bachelor, became a proponent of a self-imposed selective breeding version of eugenics. In a 1937 interview, he stated:

... man's new sense of pity began to interfere with the ruthless workings of nature. The only method compatible with our notions of civilization and the race is to prevent the breeding of the unfit by sterilization and the deliberate guidance of the mating instinct .... The trend of opinion among eugenists is that we must make marriage more difficult. Certainly no one who is not a desirable parent should be permitted to produce progeny. A century from now it will no more occur to a normal person to mate with a person eugenically unfit than to marry a habitual criminal.

In 1926, Tesla commented on the ills of the social subservience of women and the struggle of women toward gender equality, indicated that humanity's future would be run by "Queen Bees". He believed that women would become the dominant sex in the future.

In his later years Tesla became a vegetarian. In an article for Century Illustrated Magazine he wrote: "It is certainly preferable to raise vegetables, and I think, therefore, that vegetarianism is a commendable departure from the established barbarous habit." Tesla argued that it is wrong to eat uneconomic meat when large numbers of people are starving; he also believed that plant food was "superior to [meat] in regard to both mechanical and mental performance". He also argued that animal slaughter was "wanton and cruel".

In his final years he suffered from extreme sensitivity to light, sound and other influences.

Death

Tesla died of heart failure alone in room 3327 of the New Yorker Hotel, on 7 January 1943. Despite having sold his AC electricity patents, Tesla died with significant debts. Later that year the US Supreme Court upheld Tesla's patent number 645576 in a ruling that served as the basis for patented radio technology in the United States.

Bust of Tesla by Ivan Meštrović, 1952, in Zagreb, Croatia

Soon after his death Tesla's safe was opened by his nephew Sava Kosanović. Shortly thereafter Tesla's papers and other property were impounded by the United States' Alien Property Custodian office in Tesla's compound at the Manhattan Warehouse, even though he was a naturalized citizen.

Dr. John G. Trump was the main government official who went over Tesla's secret papers after his death in 1943. At the time, Trump was a well-known electrical engineer serving as a technical aide to the National Defense Research Committee of the Office of Scientific Research & Development, Technical Aids, Div. 14, NTRC (predecessor agency to the CIA's Office of Scientific Intelligence). Trump was also a professor at M.I.T., and had his feelings hurt by Tesla's 1938 review and critique of M.I.T.'s huge Van de Graaff generator with its two thirty-foot towers and two 15-foot diameter balls, mounted on railroad tracks—which Tesla showed could be out-performed in both voltage and current by one of his tiny coils about two feet tall.[106]. Trump was asked to participate in the examination of Tesla's papers at the Manhattan Warehouse & Storage Co. Trump reported afterwards that no examination had been made of the vast amount of Tesla's property, that had been in the basement of the New Yorker Hotel, ten years prior to Tesla's death, or of any of his papers, except those in his immediate possession at the time of his death. Trump concluded in his report, that there was nothing that would constitute a hazard in unfriendly hands.

At the time of his death, Tesla had been working on the Teleforce weapon, or 'death ray,' that he had unsuccessfully marketed to the US War Department. It appears that Teleforce was related to his research into ball lightning and plasma, and was conceived as a particle beam weapon. The US government did not find a prototype of the device in the safe.

After the FBI was contacted by the War Department, his papers were declared to be top secret. The personal effects were sequestered on the advice of presidential advisers; J. Edgar Hoover declared the case most secret, because of the nature of Tesla's inventions and patents. One document stated that "[he] is reported to have some 80 trunks in different places containing transcripts and plans having to do with his experiments [...]". Altogether, in Tesla's effects, there were the contents of his safe, two truckloads of papers and apparati from his hotel, another 75 packing crates and trunks in a storage facility, and another 80 large storage trunks in another storage facility. The Navy and several "federal officials" spent two days microfilming some of the stuff at the Office of Alien Properties storage facility in 1943, and that was it, until Oct., 1945.

Tesla's family and the Yugoslav embassy struggled with the American authorities to gain these items after his death because of the potential significance of some of his research. Eventually Mr. Kosanović won possession of the materials, which are now housed in the Nikola Tesla Museum.

Tesla's funeral took place on 12 January 1943, at the Cathedral of Saint John the Divine in Manhattan, New York City. His body was cremated and his ashes taken to Belgrade, Serbia, then-Yugoslavia in 1957. The urn was placed in the Nikola Tesla Museum in Belgrade.

Legacy and honors

Statue of Nikola Tesla in Niagara Falls State Park on Goat Island, New York.

Plaque honoring Nikola Tesla at New Yorker Hotel in New York City.

He did not like posing for portraits, doing so only once for princess Vilma Lwoff-Parlaghy. His wish was to have a sculpture made by his friend, Croatian sculptor Ivan Meštrović, who was at that time in United States, but he died before getting a chance to see it. Meštrović made a bronze bust (1952) that is held in the Nikola Tesla Museum in Belgrade and a statue (1955/56) placed at the Ruđer Bošković Institute in Zagreb. This statue was moved to Nikola Tesla Street in Zagreb's city centre on the 150th anniversary of Tesla's birth, with the Ruđer Bošković Institute to receive a duplicate. In 1976, a bronze statue of Tesla was placed at Niagara Falls, New York. A similar statue was also erected in his hometown of Gospić in 1986.

The SI unit tesla (T) for measuring magnetic field B (also referred to as the magnetic flux density and magnetic induction) was named in Tesla’s honor at the Conférence Générale des Poids et Mesures, Paris in 1960. The Institute of Electrical and Electronics Engineers (IEEE) of which Tesla had been vice president also created an award in recognition of Tesla. Called the IEEE Nikola Tesla Award, it is given to individuals or a team that has made outstanding contributions to the generation or utilization of electric power, and is considered the most prestigious award in the area of electric power. The crater Tesla on the far side of the Moon and the minor planet 2244 Tesla are also named after him.

Tesla was featured on several Yugoslav- and Serbian dinar notes and coins. The largest power plant complex in Serbia, the TPP Nikola Tesla is named in his honor.

The company, Tesla was a large, state-owned electrotechnical conglomerate in the former Czechoslovakia. It was renamed in Tesla's honor from the previous Electra on 7 March 1946. Some of its subsidiaries still trade in the Czech Republic.

An electric car company, Tesla Motors, named their company in tribute to Tesla. Their website states: The namesake of our Tesla Roadster is the genius Nikola Tesla [...] We‘re confident that if he were alive today, Nikola Tesla would look over our car and nod his head with both understanding and approval.

The Croatian subsidiary of Ericsson is also named 'Ericsson Nikola Tesla d.d'. ('Nikola Tesla' was a telephone hardware company in Zagreb before Ericsson bought it in the 1990s) in honor of Tesla's pioneering work in wireless communication.

UNESCO celebrated 2006 as the 150th anniversary of the birth of Nikola Tesla, scientist ; it was also being proclaimed by the governments of Croatia and Serbia to be the Year of Tesla. On the anniversary of his birth, 10 July 2006, the renovated village of Smiljan (which had been demolished during the wars of the 1990s) was opened to the public along with Tesla's house (as a memorial museum) and a new multimedia center dedicated to the life and work of Tesla. The parochial church of St. Peter and Paul, where Tesla's father had held services, was renovated as well. The museum and multimedia center are filled with replicas of Tesla's work. The museum has collected almost all of the papers ever published by, and about, Tesla; most of these were provided by Ljubo Vujovic from the Tesla Memorial Society in New York. Alongside Tesla's house, a monument created by sculptor Mile Blažević was erected. In the nearby city of Gospić, on the same date as the reopening of the renovated village and museums, a higher education school named Nikola Tesla was opened, and a replica of the statue of Tesla made by Frano Kršinić (the original is in Belgrade) was presented.

Google honoured Tesla on his birthday on 10 July 2009 by displaying a doodle in the Google search home page, that showed the G as a tesla coil.

The heavy metal group Tesla was named after Nikola Tesla.

In the years since his death, many of his innovations, theories and claims have been used, at times unsuitably and controversially, to support various fringe theories that are regarded as unscientific. Most of Tesla's own work conformed with the principles and methods accepted by science, but his extravagant personality and sometimes unrealistic claims, combined with his unquestionable genius, have made him a popular figure among fringe theorists and believers in conspiracies about "hidden knowledge". Even in Tesla's time, some believed that he was actually an angelic being from Venus sent to Earth to reveal scientific knowledge to humanity..This belief is maintained in present times by followers of Nuwaubianism.

Nikola Tesla Museum in Belgrade, Serbia

Monuments

A monument to Tesla was established at Niagara Falls, New York. This monument, portraying Tesla reading a set of notes, is a copy of a monument standing in front of the University of Belgrade Faculty of Electrical Engineering. Another monument to Tesla, featuring him standing on a portion of an alternator, was established at Queen Victoria Park in Niagara Falls, Ontario, Canada. The monument was officially unveiled on 9 July 2006 on the 150th anniversary of Tesla's birth. The monument was sponsored by St. George Serbian Church, Niagara Falls, and designed by Les Drysdale of Hamilton, Ontario. Drysdale's design was the winning design from an international competition. Belgrade International Airport is called "Belgrade Nikola Tesla Airport".

Portrayals in popular culture

Main article: Nikola Tesla in popular culture

Nikola Tesla has appeared in popular culture as a character in books, films, radio, TV, music, live theatre, comics and video games. The lack of recognition received by Tesla during his own lifetime has made him a tragic and inspirational character well suited to dramatic fiction. The impact of the technologies invented by Tesla is a recurring theme in several types of science fiction.

(source:wikipedia)