Mark Oliphant

Sir Mark Oliphant was a brilliant Australian physicist and humanitarian.

His life's work spanned from the tiniest particles of the atom to massive electrical generators. He is perhaps best known for his role in demonstrating nuclear fusion. This is the process where atomic nuclei join together to release energy. His discoveries helped explain how stars like our sun produce light and heat. He also played a critical role in developing technologies used during the Second World War.

Oliphant's scientific journey began in Adelaide, South Australia. He was born on 8 October 1901 to Harold and Beatrice Oliphant. To pay for his university studies, he worked as a cadet at the State Library of South Australia. He also worked for a manufacturing jeweler named S. Schlank & Co.

He graduated from the University of Adelaide in 1922. In 1927, his research on the properties of mercury earned him an 1851 Exhibition Scholarship. This scholarship allowed him to travel to England to study at the famous Cavendish Laboratory. He wanted to work under Sir Ernest Rutherford, one of the greatest physicists of that era.

At the Cavendish Laboratory, Oliphant worked in a high-pressure environment of discovery.

The laboratory was a center for advanced nuclear physics research. Oliphant used a particle accelerator to fire protons at various targets. Through this work, he discovered the nuclei of helium-3 and tritium. These particles are also known as helions and tritons. He proved that when these particles react, they release much more energy than they started with. This proved that energy was being liberated from inside the nucleus. This was the first experimental demonstration of nuclear fusion.

In 1937, Oliphant moved to England to become the Poynting Professor of Physics at the University of Birmingham.

He wanted to build a cyclotron, which is a type of particle accelerator. However, the outbreak of the Second World War in 1939 delayed this project. Instead, he focused on urgent wartime technology. He led a research group that created the cavity magnetron. This device was a radical new design that made microwave radar possible. This technology was vital for detecting aircraft and ships during the war.

Oliphant's influence grew as the war progressed. He was a member of the MAUD Committee, which studied the potential for atomic weapons. In July 1941, the committee reported that an atomic bomb was feasible. Oliphant helped spread this information to the United States. This effort helped launch the Manhattan Project. He later traveled to California to work at the Radiation Laboratory in Berkeley. There, he worked with Ernest Lawrence on electromagnetic isotope separation. This process provided the fissile material used in the Little Boy atomic bomb in August 1945.

After the war, Oliphant returned to Australia to help build the nation's scientific future. He became the first director of the Research School of Physical Sciences and Engineering at the Australian National University. One of his massive projects was the construction of a homopolar generator. This machine was the largest in the world, capable of 500 megajoules.

He also served as the Governor of South Australia. He was the first person born in South Australia to hold that position. He remained active in public life, even helping to found the Australian Democrats political party in 1977.

Oliphant's life was marked by both scientific triumph and personal loss. He was a lifelong vegetarian, a choice he made as a boy. He also faced physical challenges, including being deaf in one ear and needing glasses for severe astigmatism. Later in life, he became an advocate for voluntary euthanasia after witnessing his wife Rosa suffer before her death. He died in Canberra in 2000. His legacy remains in the physics of the stars and the many technologies that shaped the modern world.