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Charles H. Townes

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"Charles Townes" redirects here. For the addiction researcher, see Charles B. Towns.

Charles Hard Townes (July 28, 1915 – January 27, 2015) was an American physicist.[4][5] Townes worked on the theory and application of the maser, for which he obtained the fundamental patent, and other work in quantum electronics associated with both maser and laser devices.[6][7][8][9][10][11][12][13][14] He shared the 1964 Nobel Prize in Physics with Nikolay Basov and Alexander Prokhorov.[3][15][16] Townes was an adviser to the United States Government, meeting every US president from Harry S. Truman (1945) to Bill Clinton (1999).

Charles H. Townes
Townes in 1983
Born
Charles Hard Townes

(1915-07-28)July 28, 1915
Greenville, South Carolina, US
DiedJanuary 27, 2015(2015-01-27) (aged 99)
Oakland, California, U.S.
Alma mater
Known for
Spouse
Frances Brown
​
(m. 1941)​
Awards
Scientific career
FieldsPhysics
Institutions
ThesisConcentration of the heavy isotope of carbon and measurement of its nuclear spin (1939)
Doctoral advisorWilliam Smythe
Doctoral students

He directed the US government's Science and Technology Advisory Committee for the Apollo lunar landing program. After becoming a professor of the University of California, Berkeley in 1967, he began an astrophysical program that produced several important discoveries, for example, the black hole at the center of the Milky Way galaxy.

Townes was religious[17] and believed that science and religion are converging to provide a greater understanding of the nature and purpose of the universe.

Early life and education

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Townes had German, Scottish, English, Welsh, Huguenot French, and Scotch Irish ancestry,[18] Townes was born in Greenville, South Carolina, the son of Henry Keith Townes (1876–1958), an attorney, and Ellen Sumter Townes (née Hard; 1881–1980).[19] His brother, Henry Keith Townes Jr., (January 20, 1913 – May 2, 1990), was a renowned entomologist who was a world authority on Ichneumon wasps. Charles earned his B.S. in Physics and B.A. in Modern Languages at Furman University, where he graduated in 1935.[4] Townes completed work for the Master of Arts degree in physics at Duke University in 1937,[20] and then began graduate school at the California Institute of Technology, from which he received a Ph.D. degree in 1939.[21] During World War II, he worked on radar bombing systems at Bell Labs.[3][4]

Career and research

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In 1950, Townes was appointed professor at Columbia University.[4] He served as executive director of the Columbia Radiation Laboratory from 1950 to 1952. He was Chairman of the Physics Department from 1952 to 1955.[4]

External audio
audio icon  "The Man, the Myth, the Laser", Distillations Podcast, Science History Institute

In 1951, Townes conceived a new way to create intense, precise beams of coherent radiation, for which he invented the acronym maser (for Microwave Amplification by Stimulated Emission of Radiation). When the same principle was applied to higher frequencies, the term laser was used (the word "light" substituting for the word "microwave").[22]

During 1953, Townes, James P. Gordon, and Herbert J. Zeiger built the first ammonia maser at Columbia University.[4] This device used stimulated emission in a stream of energized ammonia molecules to produce amplification of microwaves at a frequency of about 24.0 gigahertz.[4]

From 1959 to 1961, he was on leave of absence from Columbia University to serve as vice president and director of research of the Institute for Defense Analyses in Washington, D.C., a nonprofit organization, which advised the U.S. government and was operated by eleven universities.[4] Between 1961 and 1967, Townes served as both provost and professor of physics at the Massachusetts Institute of Technology.[4] Then, during 1967, he was appointed as a professor of physics at the University of California at Berkeley, where he remained for almost 50 years; his status was as professor emeritus by the time of his death during 2015.[4] Between 1966 and 1970, he was chairman of the NASA Science Advisory Committee for the Apollo lunar landing program.

For his creation of the maser, Townes along with Nikolay Basov and Alexander Prokhorov received the 1964 Nobel Prize in Physics.[4] Townes also developed the use of masers and lasers for astronomy, was part of a team that first discovered complex molecules in space, and determined the mass of the supermassive black hole at the centre of the Milky Way galaxy.[23][24][25][26][27]

During 2002–2003, Townes served as a Karl Schwarzschild Lecturer in Germany and the Birla Lecturer and Schroedinger Lecturer in India.[4]

Townes is one of the 20 American recipients of the Nobel Prize in Physics to sign a letter addressed to President George W. Bush in May 2008, urging him to "reverse the damage done to basic science research in the Fiscal Year 2008 Omnibus Appropriations Bill" by requesting additional emergency funding for the Department of Energy's Office of Science, the National Science Foundation, and the National Institute of Standards and Technology.[28]

Astrophysics

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Galactic Center

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The Galactic Center of the Milky Way had long puzzled astronomers, and thick dust obscures the view of it in visible light. During the mid to late 1970s, Townes together with Eric Wollman, John Lacy, Thomas Geballe and Fred Baas studied Sagittarius A, the H II region at the Galactic Center, at infrared wavelengths. They observed ionized neon gas swirling around the center at such velocities that the mass at the very center must be approximately equal to that of 3 million suns.[29] Such a large mass in such a small space implied that the central object (the radio source Sagittarius A*) contains a supermassive black hole. Sagittarius A* was one of the first black holes detected; subsequently its mass has been more accurately determined to be 4.3 million solar masses.

Shapes and sizes of stars

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Townes's last major technological creation was the Infrared Spatial Interferometer with Walt Fitelson, Ed Wishnow and others. The project combined three mobile infrared detectors aligned by lasers that study the same star. If each telescope is 10 meters from the other, it creates an impression of a 30-meter lens.[30] Observations of Betelgeuse, a red giant in the shoulder of the constellation Orion, found that it is increasing and decreasing in size at the rate of 1% per year, 15% over 15 years. ISI produces extremely high angular and spatial resolution. The technology is also playing an important role in the search for extraterrestrial life in collaborations with Dan Werthimer of Search for Extraterrestrial Intelligence (SETI).[citation needed]

Personal life and legacy

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Daughters of Townes in Sweden in 1964

Townes married Frances H. Brown, an activist for the homeless,[31] during 1941. They lived in Berkeley, California and had four daughters, Linda Rosenwein, Ellen Anderson, Carla Kessler, and Holly Townes.[4]

A religious man and a member of the United Church of Christ, Townes believed that "science and religion [are] quite parallel, much more similar than most people think and that in the long run, they must converge".[32] He wrote in a statement after winning the Templeton Prize during 2005: "Science tries to understand what our universe is like and how it works, including us humans. Religion is aimed at understanding the purpose and meaning of our universe, including our own lives. If the universe has a purpose or meaning, this must be reflected in its structure and functioning, and hence in science."[33]

Science and religion

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Townes's opinions concerning science and religion were expounded in his essays "The Convergence of Science and Religion", "Logic and Uncertainties in Science and Religion", and his book Making Waves. Townes felt that the beauty of nature is "obviously God-made" and that God created the universe for humans to emerge and flourish. He prayed every day and ultimately felt that religion is more important than science because it addresses the most important long-range question: the meaning and purpose of our lives. Townes's belief in the convergence of science and religion is based on claimed similarities:

  1. Faith. Townes argued that the scientist has faith much like a religious person does, allowing him/her to work for years for an uncertain result.
  2. Revelation. Townes claimed that many important scientific discoveries, like his invention of the maser/laser, occurred as a "flash" much more akin to religious revelation than interpreting data.
  3. Proof. During this century the mathematician Godel discovered there can be no absolute proof in a scientific sense. Every proof requires a set of assumptions, and there is no way to check if those assumptions are self-consistent because other assumptions would be required.
  4. Uncertainty. Townes believed that we should be open-minded to a better understanding of science and religion in the future. This will require us to modify our theories, but not abandon them. For example, at the start of the 20th century physics was largely deterministic. But when scientists began studying the quantum mechanics they realized that indeterminism and chance play a role in our universe. Both classical physics and quantum mechanics are correct and work well within their own bailiwick, and continue to be taught to students. Similarly, Townes believes growth of religious understanding will modify, but not make us abandon, our classic religious beliefs.

Death

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Townes had steadily been active at the UCB campus, visiting and working regularly in the physics department or at the Space Sciences Laboratory past his 99th birthday and only a few months before his death.[34] Townes' health began to decline, and he died on route to the hospital in Oakland, California, on January 27, 2015, at the age of 99.[35][36][37] "He was one of the most important experimental physicists of the last century," Reinhard Genzel, a professor of physics at Berkeley, said of Townes. "His strength was his curiosity and his unshakable optimism, based on his deep Christian spirituality."[33]


Selected publications

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Townes work was published widely in books and peer-reviewed journal articles,[16] including:

  • Gordon, J.; Zeiger, H.; Townes, Charles (1955). "The Maser—New Type of Microwave Amplifier, Frequency Standard, and Spectrometer". Physical Review. 99 (4): 1264–1274. Bibcode:1955PhRv...99.1264G. doi:10.1103/PhysRev.99.1264.
  • Shimoda, K.; Wang, T.; Townes, Charles (1956). "Further Aspects of the Theory of the Maser". Physical Review. 102 (5): 1308–1321. Bibcode:1956PhRv..102.1308S. doi:10.1103/PhysRev.102.1308.
  • Schawlow, Arthur; Townes, Charles (1958). "Infrared and Optical Masers". Physical Review. 112 (6): 1940–1949. Bibcode:1958PhRv..112.1940S. doi:10.1103/PhysRev.112.1940.
  • Townes, Charles (1999). How the Laser Happened: Adventures Of a Scientist. Oxford University Press. ISBN 978-0-19-512268-8.
  • Townes, Charles; Schawlow, Arthur (1955). Microwave Spectroscopy. McGraw-Hill. ISBN 978-0-07-065095-4.
  • Townes, Charles (1995). Making Waves. Vol. 432. American Institute of Physics Press. pp. 153. doi:10.1038/432153a. ISBN 978-1-56396-381-0. PMID 15538346. S2CID 4427024. {{cite book}}: |journal= ignored (help)

Awards and honors

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Townes (right) receiving the 1964 Nobel Prize
 
Townes (right) receiving the 2006 Vannevar Bush Award

Townes was widely recognized for his scientific work and leadership.

.

 
Charles H. Townes Statue-South Main Street and Falls Park Drive, Greenville, SC-Birthplace of Townes.

References

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  1. ^ Charles Hard Townes Archived August 8, 2020, at the Wayback Machine retrieved 29 July 2020 in Wilhelmexner.org
  2. ^ a b "Professor Charles Townes ForMemRS, Foreign Member". London: Royal Society. Archived from the original on March 14, 2016.
  3. ^ a b c Boyd, Robert (2015). "Dr. Charles H. Townes (1915–2015) Laser co-inventor, astrophysicist and US presidential adviser". Nature. 519 (7543): 292. Bibcode:2015Natur.519..292B. doi:10.1038/519292a. PMID 25788091.
  4. ^ a b c d e f g h i j k l m "Charles H. Townes – Biographical". Nobelprize.org. 2006. Archived from the original on July 28, 2014. Retrieved July 29, 2014.
  5. ^ Staff. "About Charles Townes – Charles H. Townes Lecture Series". www.furman.edu. Furman University. Archived from the original on July 27, 2020. Retrieved May 1, 2020.
  6. ^ Bertolotti, Mario (2004). The History of the Laser. Taylor & Francis. ISBN 978-0-7503-0911-0.
  7. ^ Bromberg, Joan (1991). The Laser in America, 1950–1970. MIT Press. ISBN 978-0-585-36732-3.
  8. ^ Chiao, Raymond, ed. (1996). Amazing Light: A Volume Dedicated To Charles Hard Townes On His 80th Birthday. Springer. ISBN 978-0-387-94658-0.
  9. ^ Chiao, Raymond, ed. (2005). Visions of Discovery: New Light on Physics, Cosmology, and Consciousness, A Volume Dedicated to Charles Hard Townes on his 90th Birthday. Cambridge. ISBN 978-0-521-88239-2.
  10. ^ Haynie, Rachel (2014). First, You Explore: The Story of Young Charles Townes (Young Palmetto Books). University of South Carolina Press. ISBN 978-1-61117-343-7.
  11. ^ Hecht, Jeff (2005). Beam: The Race to Make the Laser. Oxford University Press. ISBN 978-0-19-514210-5.
  12. ^ Hecht, Jeff (1991). Laser Pioneers. Academic Press. ISBN 978-0-12-336030-4.
  13. ^ Taylor, Nick (2000). Laser: The Inventor, the Nobel Laureate, and the Thirty-Year Patent War. Simon & Schuster. ISBN 978-0-684-83515-0.
  14. ^ Townes, Frances (2007). Misadventures of a Scientist's Wife. Regent Press. ISBN 978-1-58790-128-7.
  15. ^ "Nobel laureate and laser inventor, Charles Hard Townes, dies at 99". Berkeley.edu. January 27, 2015. Archived from the original on January 28, 2015. Retrieved January 27, 2015.
  16. ^ a b Charles H. Townes's publications indexed by the Scopus bibliographic database. (subscription required)
  17. ^ Riess, Suzanne B. (1992). "A Life in Physics: Bell Telephone Laboratories and World War II; Columbia University and the Laser; MIT and Government Service; California and Research in Astrophysics". California Digital Library. Archived from the original on February 8, 2023. Retrieved September 4, 2016.
  18. ^ Aaserud, Finn (May 20, 1987). Charles Townes interview Archived December 22, 2019, at the Wayback Machine. American Institute of Physics
  19. ^ Stephen Farnsworth (September 10, 2010). "Notable South Carolinians- Dr. Charles Hard Townes". Indigobluesc.com. Archived from the original on October 23, 2013. Retrieved October 22, 2013.
  20. ^ "Charles Townes". The Array of Contemporary American Physicists. Archived from the original on February 23, 2016. Retrieved December 30, 2015.
  21. ^ Townes, Charles (1939). Concentration of the heavy isotope of carbon and measurement of its nuclear spin (PhD thesis). Caltech. Archived from the original on November 14, 2019. Retrieved August 27, 2019.
  22. ^ Townes, Charles (2002). How the Laser Happened. Oxford University Press. ISBN 978-0195153767.
  23. ^ "Laser inventor Charles Townes dies". The Guardian. January 29, 2015. Archived from the original on February 26, 2017. Retrieved December 14, 2016.
  24. ^ Chiao, R.; Garmire, E.; Townes, C. (1964). "Self-Trapping of Optical Beams". Physical Review Letters. 13 (15): 479–482. Bibcode:1964PhRvL..13..479C. doi:10.1103/PhysRevLett.13.479.
  25. ^ Schawlow, A.; Townes, C. (1958). "Infrared and Optical Masers". Physical Review. 112 (6): 1940–1949. Bibcode:1958PhRv..112.1940S. doi:10.1103/PhysRev.112.1940.
  26. ^ Autler, S.; Townes, C. (1955). "Stark Effect in Rapidly Varying Fields". Physical Review. 100 (2): 703–722. Bibcode:1955PhRv..100..703A. doi:10.1103/PhysRev.100.703.
  27. ^ Danchi, W. C.; Bester, M.; Degiacomi, C. G.; Greenhill, L. J.; Townes, C. H. (1994). "Characteristics of dust shells around 13 late-type stars". The Astronomical Journal. 107: 1469. Bibcode:1994AJ....107.1469D. doi:10.1086/116960.
  28. ^ "A Letter from America's Physics Nobel Laureates" (PDF). pppl.gov. May 6, 2008. Archived (PDF) from the original on October 30, 2021. Retrieved May 31, 2020.
  29. ^ Genzel, R; Hollenbach, D; Townes, C H (May 1, 1994). "The nucleus of our Galaxy". Reports on Progress in Physics. 57 (5): 417–479. Bibcode:1994RPPh...57..417G. doi:10.1088/0034-4885/57/5/001. ISSN 0034-4885. S2CID 250900662.
  30. ^ "The UC Berkeley Infrared Spatial Interferometer". isi.ssl.berkeley.edu. U. C. Berkeley. June 10, 2009. Archived from the original on December 15, 2007. Retrieved May 1, 2020.
  31. ^ "Celebrating the 100th Birthday of Frances H. Townes". Youth Spirit Artworks. January 16, 2016. Archived from the original on March 15, 2016. Retrieved March 14, 2016.
  32. ^ Harvard Gazette June 16, 2005 Laser's inventor predicts meeting of science, religion Archived March 5, 2016, at the Wayback Machine
  33. ^ a b Henry, David (January 28, 2015). "Pioneer of James Bond's Laser, Dies at 99". Bloomberg. Archived from the original on October 24, 2018. Retrieved July 22, 2015.
  34. ^ Sanders, Robert (January 27, 2015). "Nobel laureate and laser inventor Charles Townes dies at 99". Berkeley News. Archived from the original on November 8, 2020. Retrieved November 13, 2020.
  35. ^ "Inventor of the Laser Dies". Time. Archived from the original on November 8, 2020. Retrieved November 12, 2020.
  36. ^ McFadden, Robert D. (January 28, 2015). "Charles H. Townes, Who Paved Way for the Laser in Daily Life, Dies at 99 (Published 2015)". The New York Times. ISSN 0362-4331. Archived from the original on November 19, 2020. Retrieved November 13, 2020.
  37. ^ Boyd, Robert (March 2015). "Charles H. Townes (1915–2015)". Nature. 519 (7543): 292. Bibcode:2015Natur.519..292B. doi:10.1038/519292a. ISSN 1476-4687. PMID 25788091. S2CID 4384078.
  38. ^ "Book of Members, 1780–2010: Chapter T" (PDF). American Academy of Arts and Sciences. Archived (PDF) from the original on October 5, 2018. Retrieved April 7, 2011.
  39. ^ "Comstock Prize in Physics". National Academy of Sciences. Archived from the original on February 16, 2014. Retrieved February 26, 2014.
  40. ^ "Richtmyer Memorial Award". American Association of Physics Teachers. Archived from the original on December 24, 2016. Retrieved January 28, 2015.
  41. ^ "APS Member History". Archived from the original on November 30, 2022. Retrieved November 28, 2022.
  42. ^ "John J. Carty Award for the Advancement of Science". National Academy of Sciences. Archived from the original on December 29, 2010. Retrieved February 13, 2011.
  43. ^ "Golden Plate Awardees of the American Academy of Achievement". www.achievement.org. Archived from the original on December 15, 2016. Retrieved April 20, 2020.
  44. ^ Editor, ÖGV. (2015). Wilhelm Exner Medal. Austrian Trade Association. ÖGV. Austria.
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