Hermann Bondi facts for kids
Quick facts for kids
Hermann Bondi
|
|
|---|---|
 |
|
| Born | 1 November 1919 |
| Died | 10 September 2005 (aged 85) |
| Nationality | Austrian |
| Citizenship | British |
| Education | Trinity College, Cambridge (M.A., 1940) |
| Known for | Steady State theory Sticky bead argument Bondi accretion Bondi k-calculus Bondi mass Bondi–Metzner–Sachs group Lemaître–Tolman–Bondi metric Atheism |
| Awards | Gold Medal of the RSA (2001) Gold Medal od IMA (1988) Albert Einstein Medal (1983) Guthrie Medal (1973) James Scott Prize Lectureship (1960-1963) Order of the Bath (1973) Fellow of the Royal Society (1959) |
| Scientific career | |
| Fields | Mathematics Physical cosmology |
| Institutions | King's College London University of Cambridge |
| Academic advisors | Harold Jeffreys Arthur Eddington |
| Doctoral students | Felix Pirani Roger Tayler |
| 3rd Master of Churchill College, Cambridge | |
| In office 1983–1990 |
|
| Preceded by | Sir William Hawthorne |
| Succeeded by | Lord Broers |
Sir Hermann Bondi (1919–2005) was a famous Austrian-British mathematician and cosmologist. Cosmologists are scientists who study the universe and how it began.
He is best known for helping to create the Steady State theory of the universe. This idea was an alternative to the Big Bang theory. He also made important contributions to general relativity, which is Albert Einstein's theory about gravity and how it affects space and time. Bondi was the first to properly explain gravitational waves, which are ripples in space-time. He considered his work on gravitational waves to be his best scientific achievement.
Contents
Early Life & Education
Hermann Bondi was born in Vienna, Austria, in 1919. His father was a doctor. From a young age, Hermann showed amazing talent in mathematics. A family friend, Abraham Fraenkel, who was also a mathematician, suggested that Hermann meet with the famous astronomer Arthur Eddington.
Eddington encouraged Hermann to study mathematics at Trinity College, Cambridge, in England. Hermann moved to Cambridge in 1937 to escape the growing antisemitism (hatred towards Jewish people) in Austria. In 1938, just before Austria was taken over by Nazi Germany, he quickly sent a telegram to his parents, telling them to leave. They managed to escape to Switzerland and later settled in New York.
During the early part of World War II, Hermann was held in camps on the Isle of Man and in Canada. This was because he was from Austria, which was an enemy country, even though he was friendly to Britain. Other scientists, like Thomas Gold and Max Perutz, were also held there. In 1940, Bondi achieved the highest score in his mathematics exams at Cambridge, becoming a "Senior Wrangler."
By late 1941, Bondi and Gold were released. They then worked with Fred Hoyle on radar technology, which was very important for the war effort. In 1946, Hermann Bondi officially became a British citizen.
Scientific Career & Discoveries
Hermann Bondi taught mathematics at the University of Cambridge from 1945 to 1954. He was also a fellow at Trinity College during this time.
The Steady State Theory
In 1948, Bondi, along with Fred Hoyle and Thomas Gold, developed the Steady State theory. This theory suggested that the universe is always expanding, but new matter is constantly being created. This new matter would form new stars and galaxies, keeping the universe looking the same on average. This was different from the Big Bang theory, which says the universe started from a single point and has been expanding and changing ever since. The Steady State theory was eventually replaced by the Big Bang theory after scientists discovered the cosmic microwave background (CMB), which is a kind of leftover glow from the Big Bang.
Understanding Gravitational Waves
Bondi was one of the first scientists to truly understand gravitational radiation, also known as gravitational waves. These are like ripples in space and time caused by very strong events, such as black holes colliding. He introduced ideas like "Bondi radiation coordinates" and "Bondi mass" to help describe these waves.
He also helped popularize the "sticky bead argument." This idea, which some say came from Richard Feynman, helped show that gravitational waves are real and can carry energy. This was a big debate among scientists until about 1955.
Other Contributions to Astronomy
Bondi also worked on how matter falls onto stars or black holes. This process is called "accretion." He worked with Raymond Lyttleton, and his work led to terms like "Bondi accretion" and the "Bondi radius," which describe how much matter a star or black hole can pull in.
In 1954, he became a professor at King's College London. He later became an "Emeritus Professor" there in 1985, meaning he kept his title after retiring. He also served as the secretary of the Royal Astronomical Society from 1956 to 1964.
Public Service & Recognition
Beyond his work as a professor and researcher, Bondi was very active in public service. He held many important positions:
- Director-General of the European Space Research Organisation (ESRO) from 1967 to 1971. This organization later became the European Space Agency (ESA).
- Chief Scientific Adviser to the Ministry of Defence (1971–1977). This meant he gave scientific advice to the UK's defense department.
- Chief Scientific Adviser to the Department of Energy (1977–1980).
- Chairman of the Natural Environment Research Council (NERC) (1980–1984).
In 1959, he became a fellow of the Royal Society, which is a very high honor for scientists in the UK. In 1963, he even made a series of TV shows for the BBC called E=mc2, helping to explain science to the public.
He received many awards for his work, including being made a Knight Commander of the Bath in 1973, which means he was given the title "Sir." He also received the Einstein Society Gold Medal in 1983 and the Gold Medal of the Royal Astronomical Society in 2001.
One of his important public contributions was a report he wrote about the severe flooding in London in 1953. His report eventually led to the building of the Thames Barrier, a huge movable flood defense system that protects London from rising water levels.
Personal Life & Beliefs
Hermann Bondi's parents were Jewish, but he himself did not follow any religion. He was a lifelong humanist. Humanists believe that people can live good and ethical lives using reason and compassion, without needing religious beliefs. He was the president of the British Humanist Association from 1982 to 1999.
In 1947, he married Christine Stockman, who was also a mathematician and astronomer. She was a student of Fred Hoyle and also became active in the humanist movement. They had five children together: two sons and three daughters. One of their daughters, Liz Bondi, became a professor of geography.
Sir Hermann Bondi passed away in Cambridge in 2005 at the age of 85. His ashes were scattered at Anglesey Abbey near Cambridge. Christine died in 2015.
See also
In Spanish: Hermann Bondi para niños
