Hermann Bondi

1.1. Childhood and Family Background

Hermann Bondi was born in Vienna, Austria, on November 1, 1919. He was the son of a Jewish medical doctor and was raised in Vienna, where he attended the Realgymnasium. From a young age, Bondi demonstrated exceptional mathematical abilities. His mother, recognizing his talent and wishing for him to pursue mathematics, arranged for him to meet Arthur Eddington, a renowned astronomer and mathematician. This introduction was facilitated by Abraham Fraenkel, a distant relative and the only mathematician in their extended family.

1.2. Education and Wartime Experience

Encouraged by Arthur Eddington, Bondi moved to England in 1937 to study the mathematical tripos at Trinity College, Cambridge. His relocation was a direct escape from the growing antisemitism in Austria. In 1938, just before the Anschluss (the annexation of Austria by Nazi Germany), Bondi, aware of his parents' perilous situation, sent them a telegram urging them to leave Austria immediately. They successfully fled to Switzerland and subsequently settled in New York City.

During the early years of World War II, Bondi was interned as a "friendly enemy alien" due to his Austrian nationality, first on the Isle of Man and then in Canada. Among those interned with him were his future collaborators Thomas Gold and Max Perutz. In 1940, Bondi achieved the prestigious title of Senior Wrangler at the University of Cambridge, indicating his top performance in the mathematical examinations. Both Bondi and Gold were released from internment by the end of 1941. Following their release, they worked alongside Fred Hoyle on radar research at the Admiralty Signals Establishment. Bondi was granted British citizenship in 1946.

2.1. Early Academic Roles and Major Collaborations

From 1945 to 1954, Bondi served as a lecturer in mathematics at the University of Cambridge. During this period, he was also a fellow of Trinity College from 1943 to 1949 and again from 1952 to 1954. His most notable early collaborations were with Fred Hoyle and Thomas Gold, leading to one of the most influential cosmological theories of the mid-20th century.

2.2. Steady State Theory

In 1948, Hermann Bondi, in collaboration with Fred Hoyle and Thomas Gold, formulated the Steady State theory of the universe. This theory proposed that the universe is continuously expanding, but new matter is constantly created throughout space to form new stars and galaxies, thereby maintaining a constant average density of matter over time. The Steady State theory stood as a significant alternative to the Big Bang theory for several decades. However, it was ultimately eclipsed by the Big Bang model following the discovery of the cosmic microwave background (CMB) radiation, which provided strong observational evidence supporting an evolving universe.

2.3. Contributions to General Relativity

Bondi was a pioneer in correctly understanding the nature of gravitational waves in general relativity. His work introduced several key concepts and terminologies, including Bondi radiation coordinates, the Bondi k-calculus, and the notions of Bondi mass and Bondi news. He also authored influential review articles on the subject. Bondi is credited with popularizing the "sticky bead argument" (originally attributed anonymously to Richard Feynman), which helped solidify the understanding that physically meaningful gravitational radiation is indeed predicted by general relativity, a concept that remained controversial until around 1955.

His 1947 paper played a crucial role in reviving interest in the Lemaître-Tolman metric, an inhomogeneous, spherically symmetric dust solution in general relativity, often referred to as the Lemaître-Tolman-Bondi (LTB) metric. Furthermore, Bondi contributed to the theory of accretion, specifically how matter from a cloud of gas can fall onto a star or a black hole. This work, done in collaboration with Raymond Lyttleton, led to the naming of "Bondi accretion" and the "Bondi radius." Bondi was also the first to analyze the inertial and gravitational interaction of negative mass. In his 1990 autobiography, Bondi stated that his 1962 work on gravitational waves was his "best scientific work."

2.4. Later Academic Positions

In 1954, Bondi was appointed a professor at King's College London, where he continued his academic pursuits. He was later granted the title of Emeritus Professor there in 1985. Additionally, he served as the secretary of the Royal Astronomical Society from 1956 to 1964, a period during which he contributed to the broader scientific community through administrative and organizational roles.

3.1. Roles in Government and International Organizations

Bondi held numerous influential positions in government and international organizations, primarily serving as a key scientific adviser:

• Director-General of the European Space Research Organisation (ESRO) from 1967 to 1971. ESRO later merged to form the European Space Agency (ESA).
• Chief Scientific Adviser to the Ministry of Defence (United Kingdom) from 1971 to 1977.
• Chief Scientific Adviser to the United Kingdom Department of Energy from 1977 to 1980.
• Chairman of the Natural Environment Research Council (NERC) from 1980 to 1984.
• President of the Society for Research into Higher Education from 1981 to 1997.
• President of the Hydrographic Society from 1985 to 1987.
• Master of Churchill College, Cambridge from 1983 to 1990.

3.2. Contributions to Public Projects

Bondi's expertise was instrumental in various public projects. His comprehensive report following the devastating 1953 London flood was a pivotal factor that ultimately led to the construction of the Thames Barrier, a major flood defense system designed to protect London from tidal surges. He also advocated for the proposal of a Severn Barrage to generate electricity, although this large-scale energy project did not move forward. In 1963, Bondi produced a series of educational television programs for the BBC titled E=mc², which aimed to popularize scientific concepts for a broader audience. His extensive papers, spanning from 1940 to 2000, are preserved in 109 archive boxes by the Janus Project at the Churchill Archives Centre, serving as a valuable historical record of his diverse work.

5.1. Background on the Formation of Humanist Beliefs

Although Bondi was born to Jewish parents, he stated that he never "felt the need for religion." From an early age, he developed a view on religion that associated it with repression and intolerance, a sentiment he shared with his collaborator Fred Hoyle. This conviction stayed with him throughout his life and led him to actively engage with the humanist movement.

5.2. Humanist Activities

Bondi became active in British atheist and humanist circles early in his life. He served as the president of the British Humanist Association from 1982 to 1999 and was also the president of the Rationalist Press Association from 1982 until his death. He was a signatory of the Humanist Manifesto II, a document outlining a secular and ethical philosophy. Bondi took a particular interest in Indian rationalism and was a strong supporter of the Atheist Centre in Andhra Pradesh, India. He and his wife, Christine, visited the center multiple times, and a hall in its science museum is named in his honor. When he received a prestigious international award, Bondi chose to divide a significant portion of the prize money between the Atheist Centre and women's health projects in Mumbai.

8.1. Scientific Legacy

Bondi's most widely recognized scientific contribution is his co-development of the Steady State theory. While this theory was eventually superseded by the Big Bang theory due to overwhelming observational evidence, particularly the discovery of the cosmic microwave background, it played a crucial role in stimulating cosmological research and debate for several decades. His work provided a robust alternative framework that forced proponents of the Big Bang model to refine their ideas and seek stronger empirical support, ultimately advancing the understanding of the universe's origin and evolution.

Beyond cosmology, Bondi's contributions to general relativity were profound and enduring. His pioneering work in correctly understanding gravitational waves, introducing concepts such as Bondi mass and the Bondi k-calculus, laid foundational groundwork for future research in this area. His insights into negative mass and accretion theory also remain significant contributions to theoretical physics.

8.2. Public and Humanist Legacy

Bondi's extensive career in public service underscored his belief in the practical application of science for societal benefit. His roles as a scientific adviser to various UK government departments and international organizations, including the Ministry of Defence (United Kingdom) and the European Space Research Organisation, demonstrate his influence on science policy at the highest levels. His report on the 1953 London flood directly led to the construction of the Thames Barrier, a critical piece of infrastructure protecting the city.

As a lifelong humanist, Bondi was a prominent figure in the humanist movement in the United Kingdom and internationally. His presidencies of the British Humanist Association and the Rationalist Press Association, along with his support for the Atheist Centre in India, highlight his dedication to promoting rational thought, ethical living independent of religion, and social progress. His advocacy reinforced the idea that scientific thinking and human values are interconnected and vital for a progressive society.

8.3. Criticism and Controversy

The primary scientific controversy associated with Hermann Bondi is the intense debate between the Steady State theory, which he co-developed, and the rival Big Bang theory. For a period, these two models offered competing explanations for the universe's evolution. The Steady State theory faced increasing skepticism as observational evidence, such as the detection of quasars and radio galaxies, and most significantly, the discovery of the cosmic microwave background radiation in 1964, accumulated in favor of the Big Bang model. Despite the eventual rejection of the Steady State theory by the scientific mainstream, the rigorous intellectual competition it fostered significantly contributed to the advancement of modern cosmology. Its eventual decline was a testament to the scientific process of evidence-based falsification and refinement of theories.