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Ralph Alpher
Ralph Asher Alpher (February 3, 1921 – August 12, 2007) was an American cosmologist, who carried out pioneering work in the early 1950s on the Big Bang model, including Big Bang nucleosynthesis and predictions of the cosmic microwave background radiation.
Alpher was the son of a Jewish immigrant, Samuel Alpher (né Ilfirovich), from Vitebsk, Russian Empire. His mother, Rose Maleson, died of stomach cancer in 1938, and his father later remarried. Alpher graduated at age 15 from Theodore Roosevelt High School in Washington, D.C., and held the ranks of Major and Commander of his school's Cadet program. He worked in the high school theater as stage manager for two years, supplementing his family's Depression-era income. He also learned Gregg shorthand, and in 1937 began working for the director of the American Geophysical Union as a stenographer.
In 1940, he was hired by the Department of Terrestrial Magnetism of the Carnegie Foundation, where he worked with Dr. Scott Forbush under contract for the U.S. Navy to develop ship degaussing techniques during World War II. He contributed to the development of the Mark 32 and Mark 45 detonators, torpedoes, Naval gun control, Magnetic Airborne Detection (of submarines), and other top-secret ordnance work (including the Manhattan Project), and he was recognized at the end of the War with the Naval Ordnance Development Award (December 10, 1945 — with Symbol), and another Naval Ordnance Development award in 1946. Alpher's war time work been somewhat obscured by security classification.
From 1944 through 1955, he was employed at the Applied Physics Laboratory (APL). During the daytime he was involved in the development of ballistic missiles, guidance systems, supersonics, and related subjects. In 1948, he earned his Ph.D. in physics with a theory of nucleosynthesis called neutron capture, and from 1948 onward collaborated with Dr. Robert C. Herman, also at APL, on predictions of the cosmic microwave background radiation.
He earned his bachelor's degree and advanced graduate degrees in physics from George Washington University, all the while working as a physicist on contract to the Navy, and eventually for the Johns Hopkins University APL. He met Russian-Ukrainian physicist George Gamow at the University, who subsequently took him on as his doctoral student. Gamow was a prominent Soviet defector and one of the luminaries on the GWU faculty. Alpher provided much needed mathematical ability to support Gamow's theorizing.
Alpher wrote his doctoral thesis on "The Origin of the Elements", and soon after obtaining his doctorate, made the first prediction of the existence of "fossil" radiation from a hypothetical singularity—the Cosmic Microwave Background Radiation. This was observationally confirmed by Arno Allan Penzias and Robert Wilson at Bell Labs using a horn radio telescope.
While attending GWU, Alpher met Louise Ellen Simons, who was majoring in psychology at night school and working as a day secretary with the State Department. Nearly two months after the attack on Pearl Harbor, Alpher and Louise were married. At this time he had already done classified work for the U.S. Navy through the Carnegie Institution for nearly one and a half years. During a hiatus in his scientific work in early 1944, he did apply to the Navy for a commission, for which he was eligible. By this time he had done so much classified and secret work that he was no longer subject to the draft (along with about 7,000 others), and was prohibited from enlistment. That summer, he signed on to APL at Johns Hopkins University to work on another classified project — a new magnetic-influence torpedo exploder. This was badly needed since the Mark 14 torpedo, which had a poorly tested exploder that had its magnetic component turned off by order of the Chief of Naval Operations in late 1943, was badly in need of replacement (V.S. Alpher, The Submarine Review, October 2009).
Alpher's dissertation in 1948 dealt with a subject that came to be known as Big Bang nucleosynthesis. Nucleosynthesis is the explanation of how more complex elements are created out of simple elements in the moments following the Big Bang. Right after the Big Bang, when the temperature was extremely high, if any nuclear particles, such as neutrons and protons, became bound together (being held together by the attractive nuclear force) they would be immediately broken apart by the high energy photons (quanta of light) present in high density. In other words, at this extremely high temperature, the photons' kinetic energy would overwhelm the binding energy of the strong nuclear force. For example, if a proton and a neutron became bound together (forming deuterium), it would be immediately broken apart by a high energy photon. However, as time progressed, the universe expanded and cooled and the average energy of the photons decreased. At some point, roughly one second after the Big Bang, the attractive force of nuclear attraction would begin to win out over the lower energy photons and neutrons and protons would begin to form stable deuterium nuclei. As the universe continued to expand and cool, additional nuclear particles would bind with these light nuclei, building up heavier elements such as helium, etc.
Ralph Alpher
Ralph Asher Alpher (February 3, 1921 – August 12, 2007) was an American cosmologist, who carried out pioneering work in the early 1950s on the Big Bang model, including Big Bang nucleosynthesis and predictions of the cosmic microwave background radiation.
Alpher was the son of a Jewish immigrant, Samuel Alpher (né Ilfirovich), from Vitebsk, Russian Empire. His mother, Rose Maleson, died of stomach cancer in 1938, and his father later remarried. Alpher graduated at age 15 from Theodore Roosevelt High School in Washington, D.C., and held the ranks of Major and Commander of his school's Cadet program. He worked in the high school theater as stage manager for two years, supplementing his family's Depression-era income. He also learned Gregg shorthand, and in 1937 began working for the director of the American Geophysical Union as a stenographer.
In 1940, he was hired by the Department of Terrestrial Magnetism of the Carnegie Foundation, where he worked with Dr. Scott Forbush under contract for the U.S. Navy to develop ship degaussing techniques during World War II. He contributed to the development of the Mark 32 and Mark 45 detonators, torpedoes, Naval gun control, Magnetic Airborne Detection (of submarines), and other top-secret ordnance work (including the Manhattan Project), and he was recognized at the end of the War with the Naval Ordnance Development Award (December 10, 1945 — with Symbol), and another Naval Ordnance Development award in 1946. Alpher's war time work been somewhat obscured by security classification.
From 1944 through 1955, he was employed at the Applied Physics Laboratory (APL). During the daytime he was involved in the development of ballistic missiles, guidance systems, supersonics, and related subjects. In 1948, he earned his Ph.D. in physics with a theory of nucleosynthesis called neutron capture, and from 1948 onward collaborated with Dr. Robert C. Herman, also at APL, on predictions of the cosmic microwave background radiation.
He earned his bachelor's degree and advanced graduate degrees in physics from George Washington University, all the while working as a physicist on contract to the Navy, and eventually for the Johns Hopkins University APL. He met Russian-Ukrainian physicist George Gamow at the University, who subsequently took him on as his doctoral student. Gamow was a prominent Soviet defector and one of the luminaries on the GWU faculty. Alpher provided much needed mathematical ability to support Gamow's theorizing.
Alpher wrote his doctoral thesis on "The Origin of the Elements", and soon after obtaining his doctorate, made the first prediction of the existence of "fossil" radiation from a hypothetical singularity—the Cosmic Microwave Background Radiation. This was observationally confirmed by Arno Allan Penzias and Robert Wilson at Bell Labs using a horn radio telescope.
While attending GWU, Alpher met Louise Ellen Simons, who was majoring in psychology at night school and working as a day secretary with the State Department. Nearly two months after the attack on Pearl Harbor, Alpher and Louise were married. At this time he had already done classified work for the U.S. Navy through the Carnegie Institution for nearly one and a half years. During a hiatus in his scientific work in early 1944, he did apply to the Navy for a commission, for which he was eligible. By this time he had done so much classified and secret work that he was no longer subject to the draft (along with about 7,000 others), and was prohibited from enlistment. That summer, he signed on to APL at Johns Hopkins University to work on another classified project — a new magnetic-influence torpedo exploder. This was badly needed since the Mark 14 torpedo, which had a poorly tested exploder that had its magnetic component turned off by order of the Chief of Naval Operations in late 1943, was badly in need of replacement (V.S. Alpher, The Submarine Review, October 2009).
Alpher's dissertation in 1948 dealt with a subject that came to be known as Big Bang nucleosynthesis. Nucleosynthesis is the explanation of how more complex elements are created out of simple elements in the moments following the Big Bang. Right after the Big Bang, when the temperature was extremely high, if any nuclear particles, such as neutrons and protons, became bound together (being held together by the attractive nuclear force) they would be immediately broken apart by the high energy photons (quanta of light) present in high density. In other words, at this extremely high temperature, the photons' kinetic energy would overwhelm the binding energy of the strong nuclear force. For example, if a proton and a neutron became bound together (forming deuterium), it would be immediately broken apart by a high energy photon. However, as time progressed, the universe expanded and cooled and the average energy of the photons decreased. At some point, roughly one second after the Big Bang, the attractive force of nuclear attraction would begin to win out over the lower energy photons and neutrons and protons would begin to form stable deuterium nuclei. As the universe continued to expand and cool, additional nuclear particles would bind with these light nuclei, building up heavier elements such as helium, etc.
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