Edward Mills Purcell
Edward Mills Purcell (1912–1997)
|Born||August 30, 1912|
Taylorville, Illinois, United States
|Died||March 7, 1997 84) (aged|
Cambridge, Massachusetts, United States
|Alma mater|| Purdue University (BSEE)|
Harvard University (M.A.)
Harvard University (Ph.D)
|Known for|| Nuclear magnetic resonance (NMR)|
21 cm line
|Awards|| Nobel Prize for Physics (1952)|
Oersted Medal (1967)
National Medal of Science (1979)
Max Delbruck Prize (1984)
Beatrice M. Tinsley Prize (1988)
|Institutions|| Harvard University |
|Doctoral advisor||Kenneth Bainbridge|
|Other academic advisors||John Van Vleck|
|Doctoral students|| George Pake |
Charles Pence Slichter
|Other notable students||Nicolaas Bloembergen|
Edward Mills Purcell (August 30, 1912 – March 7, 1997) was an American physicist who shared the 1952 Nobel Prize for Physics for his independent discovery (published 1946) of nuclear magnetic resonance in liquids and in solids.Nuclear magnetic resonance (NMR) has become widely used to study the molecular structure of pure materials and the composition of mixtures.
The United States of America (USA), commonly known as the United States or America, is a country composed of 50 states, a federal district, five major self-governing territories, and various possessions. At 3.8 million square miles, the United States is the world's third or fourth largest country by total area and is slightly smaller than the entire continent of Europe's 3.9 million square miles. With a population of over 327 million people, the U.S. is the third most populous country. The capital is Washington, D.C., and the largest city by population is New York City. Forty-eight states and the capital's federal district are contiguous in North America between Canada and Mexico. The State of Alaska is in the northwest corner of North America, bordered by Canada to the east and across the Bering Strait from Russia to the west. The State of Hawaii is an archipelago in the mid-Pacific Ocean. The U.S. territories are scattered about the Pacific Ocean and the Caribbean Sea, stretching across nine official time zones. The extremely diverse geography, climate, and wildlife of the United States make it one of the world's 17 megadiverse countries.
Nuclear magnetic resonance (NMR) is a physical phenomenon in which nuclei in a strong static magnetic field are perturbed by a weak oscillating magnetic field and respond by producing an electromagnetic signal with a frequency characteristic of the magnetic field at the nucleus. This process occurs near resonance, when the oscillation frequency matches the intrinsic frequency of the nuclei, which depends on the strength of the static magnetic field, the chemical environment, and the magnetic properties of the isotope involved; in practical applications with static magnetic fields up to ca. 20 tesla, the frequency is similar to VHF and UHF television broadcasts (60–1000 MHz). NMR results from specific magnetic properties of certain atomic nuclei. Nuclear magnetic resonance spectroscopy is widely used to determine the structure of organic molecules in solution and study molecular physics, crystals as well as non-crystalline materials. NMR is also routinely used in advanced medical imaging techniques, such as in magnetic resonance imaging (MRI).
A molecule is an electrically neutral group of two or more atoms held together by chemical bonds. Molecules are distinguished from ions by their lack of electrical charge. However, in quantum physics, organic chemistry, and biochemistry, the term molecule is often used less strictly, also being applied to polyatomic ions.
Born and raised in Taylorville, Illinois, Purcell received his BSEE in electrical engineering from Purdue University, followed by his M.A. and Ph.D. in physics from Harvard University. He was a member of the Alpha Xi chapter of the Phi Kappa Sigma Fraternity while at Purdue.After spending the years of World War II working at the MIT Radiation Laboratory on the development of microwave radar, Purcell returned to Harvard to do research. In December 1946, he discovered nuclear magnetic resonance (NMR) with his colleagues Robert Pound and Henry Torrey. NMR provides scientists with an elegant and precise way of determining chemical structure and properties of materials, and is widely used in physics and chemistry. It also is the basis of magnetic resonance imaging (MRI), one of the most important medical advances of the 20th century. For his discovery of NMR, Purcell shared the 1952 Nobel Prize in physics with Felix Bloch of Stanford University.
Taylorville is a city in and the county seat of Christian County, Illinois, United States. The population was 11,427 at the 2000 census, making it the county's largest city.
A Bachelor of Engineering is a first professional undergraduate academic degree awarded to a student after three to five years of studying engineering at an accredited university. In the UK, a B.Eng. degree will be accredited by one of the Engineering Council's professional engineering institutions as suitable for registration as a incorporated engineer or chartered engineer with further study to masters level. In Canada, the degree from a Canadian university can be accredited by the Canadian Engineering Accreditation Board (CEAB). Alternatively, it might be accredited directly by another professional engineering institution, such as the US-based Institute of Electrical and Electronics Engineers (IEEE). The B.Eng. contributes to the route to chartered engineer (UK), registered engineer or licensed professional engineer and has been approved by representatives of the profession.
Electrical engineering is a professional engineering discipline that generally deals with the study and application of electricity, electronics, and electromagnetism. This field first became an identifiable occupation in the later half of the 19th century after commercialization of the electric telegraph, the telephone, and electric power distribution and use. Subsequently, broadcasting and recording media made electronics part of daily life. The invention of the transistor, and later the integrated circuit, brought down the cost of electronics to the point they can be used in almost any household object.
Purcell also made contributions to astronomy as the first to detect radio emissions from neutral galactic hydrogen (the famous 21 cm line due to hyperfine splitting), affording the first views of the spiral arms of the Milky Way. cm line are still an important technique in modern astronomy. He has also made seminal contributions to solid state physics, with studies of spin-echo relaxation, nuclear magnetic relaxation, and negative spin temperature (important in the development of the laser). With Norman F. Ramsey, he was the first to question the CP symmetry of particle physics.This observation helped launch the field of radio astronomy, and measurements of the 21
Astronomy is a natural science that studies celestial objects and phenomena. It applies mathematics, physics, and chemistry in an effort to explain the origin of those objects and phenomena and their evolution. Objects of interest include planets, moons, stars, nebulae, galaxies, and comets; the phenomena also includes supernova explosions, gamma ray bursts, quasars, blazars, pulsars, and cosmic microwave background radiation. More generally, all phenomena that originate outside Earth's atmosphere are within the purview of astronomy. A related but distinct subject is physical cosmology, which is the study of the Universe as a whole.
The hydrogen line, 21-centimeter line or H I line refers to the electromagnetic radiation spectral line that is created by a change in the energy state of neutral hydrogen atoms. This electromagnetic radiation is at the precise frequency of 1420405751.7667±0.0009 Hz, which is equivalent to the vacuum wavelength of 21.1061140542 cm in free space. This wavelength falls within the microwave region of the electromagnetic spectrum, and it is observed frequently in radio astronomy, since those radio waves can penetrate the large clouds of interstellar cosmic dust that are opaque to visible light.
The Milky Way is the galaxy that contains our Solar System. The name describes the galaxy's appearance from Earth: a hazy band of light seen in the night sky formed from stars that cannot be individually distinguished by the naked eye. The term Milky Way is a translation of the Latin via lactea, from the Greek γαλαξίας κύκλος. From Earth, the Milky Way appears as a band because its disk-shaped structure is viewed from within. Galileo Galilei first resolved the band of light into individual stars with his telescope in 1610. Until the early 1920s, most astronomers thought that the Milky Way contained all the stars in the Universe. Following the 1920 Great Debate between the astronomers Harlow Shapley and Heber Curtis, observations by Edwin Hubble showed that the Milky Way is just one of many galaxies. The Milky Way is a barred spiral galaxy with a diameter between 150,000 and 200,000 light-years (ly). It is estimated to contain 100–400 billion stars and more than 100 billion planets. The Solar System is located at a radius of 26,490 light-years from the Galactic Center, on the inner edge of the Orion Arm, one of the spiral-shaped concentrations of gas and dust. The stars in the innermost 10,000 light-years form a bulge and one or more bars that radiate from the bulge. The galactic center is an intense radio source known as Sagittarius A*, assumed to be a supermassive black hole of 4.100 million solar masses.
Purcell was the recipient of many awards for his scientific, educational, and civic work. He served as science advisor to Presidents Dwight D. Eisenhower, John F. Kennedy, and Lyndon B. Johnson. He was president of the American Physical Society, and a member of the American Philosophical Society, the National Academy of Sciences, and the American Academy of Arts and Sciences. He was awarded the National Medal of Science in 1979, and the Jansky Lectureship before the National Radio Astronomy Observatory. Purcell was also inducted into his Fraternity's (Phi Kappa Sigma) Hall of Fame as the first Phi Kap ever to receive a Nobel Prize.
Dwight David "Ike" Eisenhower was an American army general and statesman who served as the 34th president of the United States from 1953 to 1961. During World War II, he was a five-star general in the United States Army and served as supreme commander of the Allied Expeditionary Forces in Europe. He was responsible for planning and supervising the invasion of North Africa in Operation Torch in 1942–43 and the successful invasion of France and Germany in 1944–45 from the Western Front.
John Fitzgerald "Jack" Kennedy, commonly referred to by his initials JFK, was an American politician and journalist who served as the 35th president of the United States from January 1961 until his assassination in November 1963. He served at the height of the Cold War, and the majority of his presidency dealt with managing relations with the Soviet Union. A member of the Democratic Party, Kennedy represented Massachusetts in the U.S. House of Representatives and Senate prior to becoming president.
Lyndon Baines Johnson, often referred to as LBJ, was an American politician who served as the 36th president of the United States from 1963 to 1969. Formerly the 37th vice president of the United States from 1961 to 1963, he assumed the presidency following the assassination of President John F. Kennedy. A Democrat from Texas, Johnson also served as a United States Representative and as the Majority Leader in the United States Senate. Johnson is one of only four people who have served in all four federal elected positions.
Purcell was the author of the innovative introductory text Electricity and Magnetism.The book, a Sputnik-era project funded by an NSF grant, was influential for its use of relativity in the presentation of the subject at this level. The 1965 edition, now freely available due to a condition of the federal grant, was originally published as a volume of the Berkeley Physics Course . Half a century later, the book is also in print as a commercial third edition, as Purcell and Morin. Purcell is also remembered by biologists for his famous lecture "Life at Low Reynolds Number", in which he explained a principle referred to as the Scallop theorem.
Relativistic electromagnetism is a physical phenomenon explained in electromagnetic field theory due to Coulomb's law and Lorentz transformations.
The Berkeley Physics Course is a series of college-level physics textbooks written mostly by UC Berkeley professors.
The Scallop theorem states that to achieve propulsion at low Reynolds number in Newtonian fluids a swimmer must deform in a way that is not invariant under time-reversal. Edward Mills Purcell stated this theorem in his 1977 paper Life at Low Reynolds Number explaining physical principles of aquatic locomotion. The theorem is named for the motion of a scallop - an opening and closing of a simple hinge - which is not sufficient to create migration at low Reynolds numbers.
The Purcell effect is the enhancement of a quantum system's spontaneous emission rate by its environment. In the 1940s Edward Mills Purcell discovered the enhancement of spontaneous emission rates of atoms when they are incorporated into a resonant cavity. The magnitude of the enhancement is given by the Purcell factor
Magnetic resonance imaging (MRI) is a medical imaging technique used in radiology to form pictures of the anatomy and the physiological processes of the body in both health and disease. MRI scanners use strong magnetic fields, magnetic field gradients, and radio waves to generate images of the organs in the body. MRI does not involve X-rays or the use of ionizing radiation, which distinguishes it from CT or CAT scans and PET scans. Magnetic resonance imaging is a medical application of nuclear magnetic resonance (NMR). NMR can also be used for imaging in other NMR applications such as NMR spectroscopy.
Felix Bloch was a Swiss-American physicist and Nobel physics laureate who worked mainly in the U.S. He and Edward Mills Purcell were awarded the 1952 Nobel Prize for Physics for "their development of new ways and methods for nuclear magnetic precision measurements." In 1954–1955, he served for one year as the first Director-General of CERN. Felix Bloch made fundamental theoretical contributions to the understanding of electron behavior in crystal lattices, ferromagnetism, and nuclear magnetic resonance.
Richard Robert Ernst is a Swiss physical chemist and Nobel Laureate.
Kurt Wüthrich is a Swiss chemist/biophysicist and Nobel Chemistry laureate, known for developing nuclear magnetic resonance (NMR) methods for studying biological macromolecules.
Louis Eugène Félix Néel ForMemRS was a French physicist born in Lyon.
Paul Christian Lauterbur was an American chemist who shared the Nobel Prize in Physiology or Medicine in 2003 with Peter Mansfield for his work which made the development of magnetic resonance imaging (MRI) possible.
Sir Peter Mansfield was an English physicist who was awarded the 2003 Nobel Prize in Physiology or Medicine, shared with Paul Lauterbur, for discoveries concerning Magnetic Resonance Imaging (MRI). Mansfield was a professor at the University of Nottingham.
Behram Kurşunoğlu was a Turkish physicist and the founder and the director of the Center for Theoretical Studies, University of Miami. He was best known for his works on unified field theory, energy and global issues. Moreover, he participated in the discovery of two different types of neutrinos in late 1950s. During his University of Miami career, he hosted several Nobel Prize laureates, including Paul Dirac, Lars Onsager and Robert Hofstadter. He wrote several books on diverse aspects of physics, the most notable of which is Modern Quantum Theory (1962).
Nicolaas "Nico" Bloembergen was a Dutch-American physicist and Nobel laureate, recognized for his work in developing driving principles behind nonlinear optics for laser spectroscopy. During his career, he was a professor at both Harvard University and later at the University of Arizona.
Ramanuja Vijayaraghavan is an Indian physicist, specializing in condensed matter physics.
Erwin Louis Hahn was an American physicist, best known for his work on nuclear magnetic resonance (NMR). In 1950 he discovered the spin echo.
Phi Kappa Sigma (ΦΚΣ) is an international all-male college secret and social fraternity. While nicknames differ from institution to institution, the most common nicknames for the fraternity are Skulls, Skullhouse, Phi Kap, and PKS. Phi Kappa Sigma was founded by Dr. Samuel Brown Wylie Mitchell at the University of Pennsylvania. Mitchell recorded the initial ideas and concepts of Phi Kappa Sigma on August 16, 1850. He then began to discuss the idea with other students, first Charles Hare Hutchinson, and then Alfred Victor du Pont, John Thorne Stone, Andrew Adams Ripka, James Bayard Hodge, and Duane Williams. The seven men formally founded the fraternity on October 19, 1850 becoming the founding fathers of Phi Kappa Sigma Phi Kappa Sigma is a charter member of the North-American Interfraternity Conference, and since 2017, is headquartered in Carmel, Indiana. Prior to that, starting with its founding in 1850, the fraternity was based out of Philadelphia, Valley Forge and Chester Springs, Pennsylvania.
Yevgeny Konstantinovich Zavoisky was a Soviet physicist known for discovery of electron paramagnetic resonance in 1944. He likely observed nuclear magnetic resonance in 1941, well before Felix Bloch and Edward Mills Purcell, but dismissed the results as not reproducible. Zavoisky is also credited with design of luminescence camera for detection of nuclear processes in 1952 and discovery of magneto-acoustic resonance in plasma in 1958.
Herbert Sander Gutowsky was an American chemist who was a Professor of Chemistry at the University of Illinois at Urbana-Champaign. Gutowsky was the first to apply nuclear magnetic resonance (NMR) methods to the field of chemistry. He used nuclear magnetic resonance spectroscopy to determine the structure of molecules. His pioneering work developed experimental control of NMR as a scientific instrument, connected experimental observations with theoretical models, and made NMR one of the most effective analytical tools for analysis of molecular structure and dynamics in liquids, solids, and gases, used in chemical and medical research, His work was relevant to the solving of problems in chemistry, biochemistry, and materials science, and has influenced many of the subfields of more recent NMR spectroscopy.
Robert Vivian Pound was an American physicist who helped discover nuclear magnetic resonance (NMR) and who devised the famous Pound–Rebka experiment supporting general relativity. He became a tenured professor of physics at Harvard without ever having received a graduate degree.
Charles Pence Slichter was an American physicist, best known for his work on nuclear magnetic resonance and superconductivity.
This timeline of quantum mechanics shows the key steps, precursors and contributors to the development of quantum mechanics, quantum field theories and quantum chemistry.
Myer Bloom, was a Canadian physicist, specializing in the theory and applications of Nuclear magnetic resonance.
The history of magnetic resonance imaging includes many researchers who have contributed to the discovery NMR and described its underlying physics. Some people think it was invented by Paul C. Lauterbur in September 1971; he published the theory behind it in March 1973. The factors leading to image contrast had been described nearly 20 years earlier by Erik Odeblad and Gunnar Lindström.
The Russell Varian Prize was an international scientific prize awarded for a single, high-impact and innovative contribution in the field of nuclear magnetic resonance (NMR), that laid the foundation for the development of new technologies in the field. It honored the memory of Russell Varian, the pioneer behind the creation of the first commercial NMR spectrometer and the co-founder, in 1948, of Varian Associates, one of the first high-tech companies in Silicon Valley. The prize carried a monetary award of €15,000 and it was awarded annually between the years 2002 and 2015 by a committee of experts in the field. The award ceremony alternated between the European Magnetic Resonance (EUROMAR) Conference and the International Council on Magnetic Resonance in Biological Systems (ICMRBS) Conference. Originally, the prize was sponsored by Varian, Inc. and later by Agilent Technologies, after the latter acquired Varian, Inc. in 2010. The prize was discontinued in 2016 after Agilent Technologies closed its NMR division.
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