Thomas F Krauss

Thomas F Krauss is a physics researcher at the University of York, where he is the head of the photonics group and of the nanocentre cleanroom. Before he was head of the school of physics and astronomy at the University of St Andrews. He has several research interests, but is mostly known for his work in the field of photonic crystals, where he made the first demonstration of two-dimensional photonic band-gap effects at optical wavelengths. More recently, his research has been to use slow-light in photonic crystal waveguides in order to improve the performance of optoelectronic components.
Krauss has been at the University of St Andrews since 2000, when he set up the Photonic Crystal Research Group (now called St Andrews Microphotonics). At St Andrews, Krauss holds the chair of Professor of Optoelectronics. He is also a Fellow of the Royal Society of Edinburgh and a Fellow of the Institute of Physics, both after being elected in 2002.
Krauss has works in the field of integrated optics since 1987, when he spent one year at IBM Yorktown Heights. He completed his PhD on semi-conductor ring lasers at the University of Glasgow, where he stayed until the year 2000, excepting for one year spent at Caltech in 1997. At Glasgow, he initiated the field of study in Photonic Band-gap materials, and made the first demonstration of a 2D photonic band-gap at optical wavelengths.


Isoscalar

In particle physics, isoscalar refers to the scalar transformation of a particle or field under the SU(2) group of isospin. It is a singlet state, with total Isospin 0 and the third component of Isospin 0, much like a singlet state in a 2-particle addition of Spin.
See also isovector.


Noemi Mirkin

Noemi Mirkin from the University of Michigan, was awarded the status of Fellow in the American Physical Society, after they were nominated by their Forum on International Physics in 2007, for "her leadership in establishing productive international collaborations, her many achievements in biological molecular physics and for her long service to the international community as an officer and Executive Committee member of the Forum on International Physics."


Institute of Solid State Physics (China)

The Institute of Solid State Physics (ISSP, ) is one of over a dozen divisions comprising the Hefei Institutes of Physical Science, Chinese Academy of Sciences (CAS) situated in Hefei, Anhui. The ISSP was founded in March 1982 by the renowned scientist couple Ke T'ing-sui and He Yizhen; it now employs over 200 staff members, has combined facilities of over 25,000 square meters of laboratory space, and is a training base to over 200 graduate students in the fields of condensed matter physics, materials physics and chemistry.
The ISSP is research intensive in the areas of nano-materials technology, novel functional materials, computational physics, internal friction and defects of solids, materials physics under extreme environments, environmental and energy nanomaterials, nuclear engineering and special metallic materials. Most of its research is funded by the National Natural Science Foundation of China, the Chinese Academy of Sciences, the Natural Science Foundation of Anhui Province and the private sector. The ISSP also has close ties with the University of Science and Technology of China in both R&D and training of graduate students.


William Hayes (academic)

William Hayes (born 12 November 1930, Killorglin) is an Irish-born physicist and academic administrator, active in the United Kingdom.
Biography.
Hayes was educated at Synge Street CBS; University College, Dublin; and the University of Oxford. Hayes came to St John's College, Oxford as an Overseas Scholar in 1955. At St John's, he was Fellow and Tutor from 1960 to 1987; and Principal Bursar from 1977 to 1987. Hayes was a University Lecturer from 1962 to 1985, and Professor from 1985 to 1987. Hayes was President of St John's College, Oxford from 1987 to 2001. He was Pro-Vice-Chancellor of the University of Oxford from 1990 to 2001.
Hayes specialised in crystals, and studied imperfections in crystals and defects in solids. He investigated the spectroscopic signatures of imperfections in alkali halides and semiconductors, using varied research techniques that included inelastic light scattering (Raman and Brillouin spectroscopy), magneto-optics (Zeeman effect), nuclear magnetic resonance (NMR), electron paramagoetic resonance (EPR) and muon spin resonance (mu-SR).
His publications included the books:
In 1990 he was elected a Fellow of the American Physical Society for "creative applications of spectroscopy and laser techniques to the understanding of defects in solids. phase transitions, and semi-conductor physics"
Hayes married Joan Ferris in 1962. Their marriage produced three children, and lasted until her death in 1996.


Rashmi C. Desai

Rashmi C. Desai is an Indian-American physicist, professor emeritus of physics at the University of Toronto.
He first studied physics at the University of Mumbai, where he obtained a Bachelor of Science degree in 1957. He worked as a scientific officer at the Bhabha Atomic Research Centre in Mumbai, India, from 1957 to 1962.
He then moved to the US and earned a Ph.D from Cornell University, Ithaca, New York, in 1966 before working as a research associate at the Massachusetts Institute of Technology in Cambridge, Massachusetts from 1966 to 1968. In the latter year he joined the University of Toronto as an assistant professor, becoming a full professor in 1978, a position he held until his retirement in 2006.
Awards and accolades.
From the University of Toronto, Desai was awarded the status of Fellow of the American Physical Society in 2001 after being nominated by the Topical Group on Statistical and Nonlinear Physics, for "applications of statistical mechanics to materials science, including: phase separation and ordering kinetics in systems with competing interactions, Langmuir films, ferromagnetic films, epitaxially grown solid films, order-order transitions in polymers."


Seed nucleus

A seed nucleus is an isotope that is the starting point for any of a variety of fusion chain reactions. The mix of nuclei produced at the conclusion of the chain reaction generally depends strongly on the relative availability of the seed nucleus or nuclei and the component being fused--whether neutrons as in the r-process and s-process or protons as in the rp-process. A smaller proportion of seed nuclei will generally result in products of larger mass, whereas a larger seed-to-neutron or seed-to-proton ratio will tend to produce comparatively lighter masses.


Streamer (software)

Streamer is a radiative transfer code (Key and Schweiger, 1988) to calculate radiances (intensities) or irradiances in the atmosphere.
The code uses N-stream approximation to the radiative transfer equations (Stamnes et al. 1988) and allows for flexible choice of bands. The code can be used both for satellite radiance applications and estimates of heating rates in both cloudy and non-cloudy atmosphere. One can specify surface reflectivity. Streamer is written in FORTRAN.
FluxNet.
FluxNet, the neural network version of Streamer, calculates upwelling and downwelling surface flux in either shortwave or longwave. It is less flexible than Streamer but is two to four times faster.


Optical Fiber Technology

Optical Fiber Technology is a scientific journal that is published by Elsevier (formerly by Academic Press). Established in 1994, it covers various topics in fiber-optic engineering, optical communications and fiber lasers.


Marion Asche

Marion Asche (January 7, 1935 – December 11, 2013) was a German physicist and professor of solid state physics. She is known for her pioneering work in semiconductor physics.


Robert Horace Baker

Robert Horace Baker (born March 29, 1883 in Northampton, Massachusetts; died June 23, 1964 in Upland, California) was an astronomer.
Career.
Educated at Amherst College, he graduated with an A.B. in 1904 and A.M. the following year. His graduate work in astronomy was done at the University of Pittsburgh where he was an assistant at Allegheny Observatory and where he obtained the Ph.D. degree in 1910. Dr. Baker was also awarded an honorary D.Sc. by Oglethorpe University in 1936.
Dr. Baker’s first post was that of Assistant Professor at Brown University's Ladd Observatory (1910-1911) and he then became a Professor at the University of Missouri in 1911, a post he held until 1922. While there he used a visual photometer at Laws Observatory to study variable stars.
In 1922 he left Missouri, frustrated at an inability to obtain a more modern observatory. After a year as Kellogg Fellow at Lick Observatory in California, he was appointed Professor of Astronomy and Director of the University of Illinois Observatory in 1923. While at Lick, he used the photoelectric photometer on the 12-inch telescope to study u Herculis. He continued working on photoelectric photometry when he arrived at Illinois.
In 1931-1932 and again in 1938-39 he was a Research Associate of Harvard University while on sabbatical working with Bart Bok’s Star Count Circuit. Starting in 1939, he changed his research focus to the Milky Way and Galactic Structure.
Dr. Baker’s professional activities extended through many fields. His research publications run to more than forty articles in the areas of galactic structure, extragalactic nebulae cataloguing, variable star measurement, solar corona structure, and others. He was an exceptionally fine observer and possessed the added talent of clarity of style that made his articles models of scholarly writing. It is characteristic of his abiding interest in astronomy that he continued to publish research after becoming emeritus. His students include Elaine Nantkes, Lois Kiefer, David Heeschen, and Allan Sandage.
Author.
He enjoyed great success with his textbooks "Astronomy" and "An Introduction to Astronomy", both published by Van Nostrand, which have gone through many editions and numerous revisions. Reviewers invariably refer to them as “classics” and as the “standard by which other texts in astronomy are measured.” Otto Struve call "An Introduction to Astronomy" an excellent textbook that set a high standard. Dr. Baker took special pride in these books as indicated by the fact that he kept them up to date with periodic revisions even after retirement.
His very marked ability as an author served him well also in the field of popular astronomy. His books "The Universe Unfolding", "When the stars come out", "Introducing the Constellations", and "Stars: A Guide to the Heavens" (the last in collaboration with Herbert Zim) are known and esteemed the world over.
Among the professional societies in which he held membership are the American Astronomical Society, the American Association for the Advancement of Science, the American Physical Society, the Royal Astronomical Society, and Sigma Xi. Dr. Baker held this post until his retirement from the University of Illinois in 1951, having also been an Assistant Dean of the Graduate College in 1949-1951.
Family.
Robert Baker's parents were Horace Hall Baker and Ellen H. Puffer.
Robert married Rose Koenig of Goldendale, Washington, in 1911 in Ann Arbor, Michigan. They had two children, Ralph (born 1913) and Ruth (born 1914). Rose died in February 1925 of pneumonia.
He married Mary Howe in June 1926 and had one son, Robert Howe Baker, born 1927, died 1983. Mary Howe was the daughter of Louis McHenry Howe, secretary and advisor to President Franklin Roosevelt.


Leslie Hodson

Leslie Hodson (born Fishlake 15 July 1925 – died Leeds 1 March 2010) was an English physicist who discovered the kaon (K+ meson) sub-atomic particle in 1954.
Hodson was educated at Thorne Grammar School and the University of Manchester. After three years as a research associate at Princeton he became a lecturer at the University of Leeds. He retired in 1990.


International School for Advanced Studies

The Scuola Internazionale Superiore di Studi Avanzati (SISSA) is an international, state-supported, post-graduate-education and research institute, located in Trieste, Italy.
SISSA is active in the fields of mathematics, physics, and neuroscience, offering both undergraduate and post-graduate courses.
Each year, about 70 PhD students are admitted to SISSA based on their scientific qualifications. SISSA also runs master's programs in the same areas, in collaboration with both Italian and other European universities.
History.
SISSA was founded in 1978, as a part of the reconstruction following the Friuli earthquake of 1976. Although the city of Trieste itself did not suffer any damage, physicist Paolo Budinich asked and obtained from the Italian government to include in the interventions the institution of a new, post-graduate teaching and research institute, modeled on the Scuola Normale Superiore di Pisa. The school became operative with a PhD course in theoretical physics, and Budinich himself was appointed as general director.
In 1986, Budinich left his position to Daniele Amati, who at the time was at the head of the theoretical division at CERN. Under his leadership, SISSA expanded its teaching and research activity towards the field of neuroscience, and instituted a new interdisciplinary laboratory aiming at connecting humanities and scientific studies.
From 2001 to 2004, the director was the Italian geneticist Edoardo Boncinelli, who fostered the development of the existing research areas. Other directors were appointed in the following years, which saw the strengthening of SISSA collaboration with other Italian and European universities in offering master's degree programs in the three areas of the School (mathematics, physics and neuroscience).
The physicist Stefano Ruffo, the current director, was appointed in 2015. He signed a partnership with the International Centre for Genetic Engineering and Biotechnology to set up a new PhD program in Molecular Biology, with teaching activity organized by both institutions.
Organization.
SISSA houses the following research groups:
In addition, there is the "Interdisciplinary Laboratory for Natural and Humanistic Sciences" (now LISNU - Laboratorio Interdisciplinare Scienze Naturali e Umanistiche), which is endowed with the task of making connections between science, humanities, and the public. It currently offers a course in Scientific Communication and Scientific journalism.
SISSA also enjoys special teaching and scientific links with the International Centre for Theoretical Physics, the International Centre for Genetic Engineering and Biotechnology and the "Elettra" Synchrotron Light Laboratory.
Services.
The School provides students and members of other scientific institutions in the Trieste area with specialised Mathematics and Physics libraries, a parallel Calculus Centre, several cellular-neurobiology laboratories, a confocal microscopy and an electronic microscopy laboratory and multiple cognitive-neuroscience laboratories. In the school premises there is also a canteen, a kindergarten and a gym, open to SISSA staff and students. In the school garden there is an open air theatre, used for shows, conferences and activities that aim to promote science to a wider public.
Recently SISSA, in partnership with the International Centre for Theoretical Physics, built a new supercomputing centre in Miramare, near Trieste, with about 100 teraFLOPS of computing power.
Ranking.
According to the last aggregate data issued by ANVUR - the Italian National Agency for the Evaluation of the University and Research Systems - SISSA ranks:
Campus.
Since July 13, 2010 the campus has been located near Opicina, where it is easily accessible by Opicina tramway.
Up to 2010 SISSA administrative offices and all research sectors were located near the Miramare Park, about 10 kilometres from the city of Trieste. Miramare park still hosts the ICTP (International Center for Theoretical Physics) and the Department of Theoretical Physics of the University of Trieste.


Irving C. Gardner

Irvine Clifton Gardner (1889 – December 29, 1972) was president of the Optical Society of America in 1958.


Luigi Puccianti

Luigi Puccianti (; 11 June 1875 – 9 June 1952) was an Italian physicist.
Career.
In 1899-1900, Puccianti constructed a highly sensitive spectrograph, with which he studied the infrared absorption of many compounds and attempted to correlate the spectra with molecular structure. He studied the emission spectra of metals and halogens and proposed measuring the wavelength of X-rays by using a diffraction grating at large angles of incidence.
Puccianti was, at one time, the academic advisor to Nobel prize winner Enrico Fermi. He once said there was little he could teach Fermi, and often asked Fermi to teach him something instead.


Tachyons in fiction

The hypothetical particles tachyons have inspired many occurrences of in fiction. The use of the word in science fiction dates back at least to 1970 when James Blish's Star Trek novel "Spock Must Die!" incorporated tachyons into an ill-fated transporter experiment.
In general, tachyons are a standby mechanism upon which many science fiction authors rely to establish faster-than-light communication, with or without reference to causality issues. For example, in the "Babylon 5" television series, tachyons are used for real-time communication over long distances. Another instance is Gregory Benford's novel "Timescape", winner of the Nebula Award, which involves the use of tachyons to transmit a message of salvation back in time. Likewise, John Carpenter's horror film "Prince of Darkness" uses tachyons to explain how future humans send messages backward through time to warn the characters of their impending doom. By contrast, Alan Moore's classic comic book limited series "Watchmen" features a character who uses "a squall of tachyons" broadcasting from space to muddle the mind of the only person on Earth capable of seeing the future.
The word "tachyon" has become widely recognized to such an extent that it can impart a science-fictional "sound" even if the subject in question has no particular relation to superluminal travel (compare positronic brain). Classic Anime fans may associate tachyons with the energy source for the wave-motion gun and wave-motion engine in "Space Battleship Yamato" ("Starblazers" in the United States). Further examples include the "Tachion Tanks" of the PC game ' and the "tachyon beam" of the game "Master of Orion." The space-combat sim ' utilizes "tachyon gates" for superluminal travel but gives no exact explanation for the technology, and the MMORPG "Eve Online" features six types of "Large Tachyon Lasers", technically a contradiction since by definition, lasers emit light—photons, not any kind of hypothetical tachyon.


Norman Holter

Norman Jefferis "Jeff" Holter (February 1, 1914 – July 21, 1983) was an American biophysicist who invented the Holter monitor, a portable device for continuously monitoring the electrical activity of the heart for 24 hours or more. Holter donated the rights to his invention to medicine.
Early life and education.
Holter was born February 1, 1914 in Helena, Montana. He graduated from Carroll College in 1931 and then continued his studies at University of California Los Angeles, graduating from there with a master's degree in physics in 1937. He then graduated a year later from the University of Southern California with a master's degree in chemistry. He continued his education by completing postgraduate work at the University of Heidelberg (Germany), the University of Chicago, the Oak Ridge Institute of Nuclear Studies, and the University of Oregon Medical School.
Career.
During World War II, Holter served as senior physicist in the U.S. Navy, studying the characteristics of waves. In 1946, he headed a government research team involved in the atomic-bomb testing at Bikini Atoll. After the war, he continued work with the United States Atomic Energy Commission, and served as president of the Society of Nuclear Medicine from 1955 to 1956. In 1964, he became a full professor at the University of California, San Diego, coordinating activities at the Institute of Geophysics and Planetary Physics. In 1979, the Association for the Advancement of Medical Instrumentation (AAMI) awarded Holter with the AAMI Foundation Laufman-Greatbatch Prize for his contributions to medical technology.
Holter was the son and grandson, respectively, of Montana pioneers Norman B. Holter and Anton M. Holter. Anton M. Holter was born in his native Norway and emigrated to the United States when he was 23. Numerous landmarks in and around Helena, Montana bear his family's name. These landmarks include The Holter Museum of Art, Holter Dam, and Holter Lake. The Holter Art Museum is widely recognized as the premiere modern western art museum in the United States and attracts the talents and attention of international crowds.


David MacAdam

David Lewis MacAdam (July 1, 1910 – March 9, 1998) was an American physicist and color scientist who made important contributions to color science and technology in the fields of colorimetry, color discrimination, color photography and television, and color order.
Education.
MacAdam grew up in Upper Darby outside of Philadelphia, graduating from Upper Darby High School in 1928, attended Lehigh University, and in 1936 received a PhD in physics from MIT. Under Prof. Arthur C. Hardy, he originated the first course in color measurement and assisted Hardy in the preparation of “Handbook of Colorimetry,” published in 1936.
Career.
Upon graduation MacAdam joined the Research Laboratories of the Eastman Kodak company in Rochester, NY, from where he retired as a Senior Research Associate in 1975. Subsequently, he was named Adjunct Professor at the University of Rochester, Institute of Optics where he remained active until 1995.
At Eastman Kodak, among many other things, he helped to establish the theoretical basis for color photography, including color masking as compensation for unwanted dye layer absorptions.
Optimal object color limits.
While still studying, MacAdam published in 1935 two papers on the theory of optimal object colors in which he showed the results of his calculations of the optimal object color solid raised over the CIE chromaticity diagram, using the newly established CIE standard observer and illuminant C and A data from 1932.
MacAdam ellipses.
One of MacAdam's best known contributions was in support of technological color control. Assuming that the basis of color difference perception was the statistical error in matching the appearance of a given color stimulus he conducted an extensive experiment with one observer, the result of which was expressed in the CIE chromaticity diagram in form of statistically derived ellipses, published in 1942 (See Fig. 1). However, the resulting Friele–MacAdam–Chickering color difference formula proved less effective in predicting perceived color differences than formulas derived on other bases. In attempting to convert the ellipses to circles of equal size MacAdam encountered the non-Euclidean nature of psychophysical color space.
Instrumentation and computation.
In the mid-1940s MacAdam pioneered the use of computers in colorimetric computations, established Hardy's reflectance spectrophotometer as a reliable industrial measuring instrument, and invented a tristimulus integrator as an accessory.
Principal component analysis of daylight.
With Deane B. Judd and Günter Wyszecki, MacAdam performed the first principal-component analysis of phases of daylight of various correlated color temperatures, demonstrating that they can be represented as linear combinations of a limited number of spectral components.
Optical Society of America Uniform Color Scales.
MacAdam was a leading member of the committee of the Optical Society of America that in 1947, at the suggestion of the U.S. National Research Council, began work on a perceptually uniform colorimetric model of the color solid. Upon the retirement of its first chairman D. B. Judd, MacAdam was elected chair. The result of the committee's work was published in 1974 as ‘Uniform Color Scales,’ with OSA publishing a related color atlas with 558 samples in 1977.
Publications.
In addition to his contributions to "Handbook of Colorimetry" (1936) he was a major contributor to OSA's 1953 book "The Science of Color". His interest in the history of color science resulted in publication in 1970 of "Sources of Color Science", a compilation of 26 seminal papers on color science, from Plato to Le Gros Clark, several translated for the first time into English. In 1981 he published "Color Measurement: Theme and Variations", a presentation of fields of color science in which he has made important contributions. He is also the author of some 100 peer-reviewed journal articles.
MacAdam was president of the Optical Society of America in 1963 and editor of the "Journal of the Optical Society of America" from 1964 to 1975. He was active in the Inter-Society Color Council and the Commission Internationale de l’Eclairage (CIE). He received honors from many societies, including the Frederic Ives Medal of the Optical Society of America in 1974.


UA5 experiment

The UA5 experiment was the first experiment conducted at the Proton-Antiproton Collider (SpS), a collider using the infrastructure of the Super Proton Synchrotron (SPS). The experiment was approved in February 1979, as a collaboration between CERN and the universities of Bonn, Brussels, Cambridge and Stockholm. The spokesperson of the UA5 collaboration was John Rushbrooke.
The object of the experiment was to investigate Centauro events and more generally to perform a first rapid visual survey of the energy region afforded by the then new SPS collider. Measurements were done on proton-antiproton collisions of 540 GeV center-of-mass energy, with the results being published in November 1983. Later, under the name of UA5/2, data was recorded from 900 GeV collisions. No indication of Centauro production was observed, but an upper limit on the production was obtained.
The experimental setup consisted of two large streamer chambers which were placed above and below the SpS beam pipe. The chambers were triggered by requiring hits in scintillation counters at each end. This trigger rejected essentially all elastic and diffractive elements. The streamer chamber tracks were photographed by six cameras, and the tracks were measured, reconstructed and analyzed.


Nadiashda Galli-Shohat

Nadiashda or Nadejda Galli-Shohat (died March 6, 1948) was a Russian physicist. Born Nadiashda Kokaoulina in Siberia, she graduated from the Women's University of Petrograd in 1903, joined the Bolshevik Party after the 1905 Russian Revolution, and took the name Galli upon marrying her first husband. She received her doctorate from Göttingen in 1914, worked at the Yekaterinburg Meteorological Observatory from 1915 to 1917, and from 1917 to 1922 was professor and chair of the physics department at Ural Federal University, after which she worked at the University of Petrograd's State Optical Institute. Together with her second husband, the mathematician James Alexander Shohat, she migrated to the United States in 1923. She was elected a Fellow of the American Physical Society in 1931. She taught physics at the University of Michigan, Mount Holyoke, Rockford College, Bryn Mawr, and the University of Pennsylvania.
In addition, Galli-Shohat is known for a biography of her nephew, the composer Dmitri Shostakovich, coauthored by her and Victor Seroff. Titled "Dmitri Shostakovich: The Life And Background Of A Soviet Composer", it was published by Alfred A. Knopf in 1943. Galli-Shohat died on March 6, 1948 at the Graduate Hospital in Philadelphia.


Morris B. Crawford

Morris Barker Crawford (September 26, 1852 – 1940) was an American academic, and the first professor of physics at Wesleyan University in Middletown, Connecticut.
Early life and education.
He was born in 1852 in Sing Sing, now Ossining, New York to the Rev. Morris DeCamp Crawford and Charlotte (Holmes) Crawford. Both his father and his grandfather were ministers.
He graduated from Wesleyan University in 1874, and he was a member of the Eclectic Society and of Phi Beta Kappa. He earned a Master of Arts degree from Wesleyan in 1877.
Career.
He was a tutor in Mathematics at Wesleyan from 1874-1877. He also served as registrar. From 1877-1880, he studied Mathematics and Physics at the University of Leipsic and the University of Berlin.
He was appointed an instructor of Physics in 1880, an associate professor in 1881, and a full professor in 1884. He was the first physics professor at Wesleyan, the Foss Professor of Physics. He retired in 1921, and was elected Professor Emeritus.
He was a fellow of the American Association for the Advancement of Science and a member of the American Physical Society.
He was a member of the First Methodist Episcopal Church of Middletown beginning in his freshman year in college, and was active in the church throughout his life. This included rebuilding the church after fires in 1885 and 1930. He was very involved with the Eclectic Society, and supervised construction of its Henry Bacon-designed clubhouse in 1908.
Family life.
Crawford married Caroline Laura Rice (1856-1954) on December 25, 1883. She was the daughter of the Rev. Dr. William Rice, a noted Methodist minister and librarian who had also attended Wesleyan University. She graduated from Wesleyan in 1879, was elected to Phi Beta Kappa, and earned a master's degree in 1882. Morris B. Crawford was a proponent of coeducation at Wesleyan, and he met his wife while they were both students at the university. They had three children; Holmes Crawford (1884-1886), Frederick North Crawford (1886-1922), who graduated from Wesleyan in 1908, and became a chemist, and Margaret Crawford (1889-1929), who graduated with high honors from Wesleyan in 1910.
They are buried at Indian Hill Cemetery in Middletown, Connecticut.


Guenakh Mitselmakher

Guenakh Mitselmakher is a Russian-American physicist, since 2004 the Distinguished Professor in the Institute for High Energy Physics and Astrophysics at the University of Florida (UFL). His main interests are in gravitational waves and experimental particle physics.
Career.
He earned his Ph.D at Joint Institute for Nuclear Research, Dubna, Russia in 1974. After working in Dubna for some years he emigrated in 1991 to the US to work on the Superconducting Super Collider project (SSC) in Dallas, Texas. When the project was cancelled in 1993 he transferred to work on the Compact Muon Solenoid project (CMS), working at the Fermi National Accelerator Laboratory in Chicago from 1994-1998. In 1995 he was also appointed Professor of Physics at UFL, rising to Distinguished Professor in 2004.
On September 14, 2015, he contributed to the discovery of GW150914 using his real-time search program Coherent WaveBurst, which identified gravitational wave signals in the Laser Interferometer Gravitational wave Observatory (LIGO) data received at detectors in Livingston, Louisiana and Hanford, Washington.
He was elected a Fellow of the American Physical Society in 2001 "for his early measurement of the pion charge radius and for his leadership role in the design of innovative very high rate muon detectors at hadronic colliders".


Lou Bloomfield

Louis Aub Bloomfield is a physics professor at the University of Virginia. Bloomfield became a fellow of the American Physical Society in 1994 for his work on cluster magnetism and has received several other significant honors. Bloomfield is often referenced as a physics authority in major news publications.
Early life.
Bloomfield was born in Boston, Massachusetts in October 1956. He lived in Cleveland, Ohio and Urbana, Illinois, graduating from Urbana High School in 1974. Bloomfield attended Amherst College, winning the LeRoy Apker Award in his senior year. He was most interested in medicine after graduating from Amherst, but his physics professors pressured him to apply to three prestigious physics programs in addition to taking the MCAT and applying to medical school at Johns Hopkins University. Bloomfield was accepted into all three physics programs and medical school, but decided to go into physics after asking himself whether he really wanted to be "cutting apart dead bodies in Baltimore." Bloomfield attended Stanford University for physics, receiving his Ph.D. from the school in 1983. He began teaching at the University of Virginia two years later after a postdoc at Bell Laboratories.
Career.
Bloomfield began teaching physics at the University of Virginia in 1985. He developed and began teaching a course entitled "How Things Work" in 1991, which he has since taught to thousands of students. This course's success, along with the publishing of a textbook on the subject under the same title, has led to Bloomfield doing a number of interviews and explanations as a guest for large news companies. Bloomfield's explanations of everyday activities and questions have been featured in USA Today, Huffington Post, and the Washington Post, where he did a series of explanations on sports during the 2016 Summer Olympics. Bloomfield worked with UVA to create an instructional video on social distancing during the COVID-19 pandemic.
Inventions.
Bloomfield has expertise in the field of borosilicate materials and has developed multiple products using this technology. Borosilicates are viscoelastic (a portmanteau of "viscous" and "elastic"), a property that is useful in multiple areas. These inventions include Vistik, a material designed for use in stabilizing wobbly tables, and EarJellies, which are earplugs made from a similar material.


Oreste Piccioni

Oreste Piccioni (October 24, 1915 – April 13, 2002) was an Italian-American physicist who made important contributions to elementary particle physics during the early years of its history.
He was a graduate student of Enrico Fermi at the University of Rome, receiving his doctorate in 1938.
Remaining in Italy during World War II, he did fundamental research under difficult conditions in the basement of a high school, which first clarified the nature of the muon.
Biography.
In 1946 he emigrated to the United States, where he worked first at MIT with Bruno Rossi, and then at BNL's Cosmotron, developing faster nuclear electronics and essential techniques for extracting, transporting, and focusing beams of high energy particles.
Later at UC Berkeley's Lawrence Radiation laboratory he was a co-discoverer of the antineutron in 1955 at the Bevatron.
His important contributions to the design of the experiment that discovered the antiproton in 1955 were acknowledged in the 1959 ceremony in which the Nobel Prize in physics was awarded to E. Segrè and O. Chamberlain.
Unfortunately a famous quarrel over credit and priority for the discovery embittered Piccioni for much of his later life, to the point that he filed a lawsuit in 1972 against Segrè and Chamberlain, seeking damages and public acknowledgment of his contributions. The suit was ultimately dismissed as filed too late for consideration of the issues.
An important theoretical paper
with Abraham Pais in 1955 considered regeneration in neutral kaon mixing.
In 1960 he joined the faculty of the University of California, San Diego (UCSD), where his group made the first measurement of the neutral kaon K1-K2 mass difference.
Piccioni retired from UCSD as Professor Emeritus in 1986, but continued to give review talks and work in the investigation of fundamental problems in quantum mechanics.
In 1999 he was awarded the Matteucci Medal by the Accademia Nazionale delle Scienze (National Academy of Sciences) in Italy.


Tom Foxon

Tom Charles Bayley Foxon FRS is a British physicist, and emeritus professor at the University of Nottingham.


Anna Grassellino

Anna Grassellino (born 1981) is an Italian electronic engineer, Senior Scientist and Deputy Head of the Applied Physics and Superconducting Technology Division at Fermilab. In 2017, she was awarded the Presidential Early Career Award for Scientists and Engineers by Barack Obama. In 2019 Grassellino became the Deputy Chief Technology Officer at Fermilab.
Early life and education.
Grassellino is from Marsala, Italy. She attended the Scientific High School of Marsala graduating cum laude. She studied electronic engineering at the University of Pisa, graduating in 2005 with a thesis in microelectronics. She spent the summer of 2004 as an intern at Fermilab and met Nigel Lockyer. She joined the University of Pennsylvania for her graduate studies as she wanted to study free from gender bias. For her doctorate, she specialized in superconducting radio frequency technology and applied physics working with Nigel Lockyer. In 2009 she was awarded the top young researcher poster prize at the International Particle Accelerator Conference. She worked in Philadelphia and at TRIUMF in Vancouver, and eventually graduated in 2011.
Research and career.
Grassellino was appointed as a postdoctoral researcher at Fermilab in 2012. She was then appointed Scientist in 2015 and Senior Scientist in 2018. Grassellino has covered leadership roles at Fermilab starting from group leader in 2014 to Deputy Division Head in 2016 and Deputy Chief Technology Officer in 2019. She currently manages an Associate Professor position at Northwestern University where she is Co-Director of the Center for Applied Physics and Superconducting Technology (CAPST). She is known for her pioneering work in superconducting radio frequency cavities for next generation particle accelerators. As a postdoc, Grassellino experimented with introducing a small amount of nitrogen into the inner surface of the cavities, which are made of niobium and surface treated using electropolishing. She and her group noticed that residual nitrogen remaining in the cavity systematically improved the RF superconductivity response. By baking the niobium SRF cavities at high temperatures in the presence of nitrogen, the Q factors more than tripled; dramatically reducing the cryogenic costs of the large accelerator facilities. She made the discovery of nitrogen doping by accident, hoping to create niobium nitride but instead found with her FNAL group - via material and surface science studies - that the real effect was due to nitrogen as interstitial. Superconducting radio frequency cavities generate high energy with high current and expel magnetic flux, which can result in power dissipation. The technology has been adopted as the standard for SRF cavities and used in laboratories all over the world, as well as private firms. The LCLS-II HE upgrades at SLAC are the first world class accelerator facilities to be built entirely with the nitrogen doping technology. In 2015 she was awarded a $2.5 million Early Career Award from the United States Department of Energy, which allowed her to employ postdocs.
Grassellino has given several international talks, including the keynote talk at the American Association for the Advancement of Science Innovations in Accelerator Science conference in 2015. In 2016 she hosted Matteo Renzi at Fermilab, who asked her to support him in representing Italians Abroad. She won the Institute of Electrical and Electronics Engineers Particle Accelerator Science and Technology Award in 2016, the U.S. Particle Accelerator School's Prize for Achievement in Accelerator Physics and Technology in 2017, and the 2017 Frank Sacherer Prize for early-career achievement in the accelerator field. She was awarded the Presidential Early Career Award for Scientists and Engineers in 2017 from Barack Obama. She has given popular science lectures in Italy and America. She is the co-director of the Fermilab and Northwestern Center for Applied Physics and Superconducting Technologies (CAPST). In 2018 she was awarded the highest honour of the Rotary Club of Marsala Lilibeo.
Honors.
In 2020, Grassellino was elected Fellow of the American Physical Society.


Anke Kracke

Anke Kracke (born Anke Wagner, 8 September 1983 in Mainz) is a German experimental physicist affiliated with the Max Planck Institute for Nuclear Physics, Heidelberg (MPIK).
Kracke studied physics at the Johannes Gutenberg University of Mainz. In 2007, she began doctoral work with Klaus Blaum at MPIK. She defended her thesis, "The g-factor of the valence electron bound in lithiumlike silicon 28Si11+: The most stringent test of relativistic many-electron calculations in a magnetic field", in 2013. She subsequently worked as a post-doctoral researcher at Florida State University with Edmund G. Myers.
In 2012, she won the Helmholtz Prize for precision measurements together with her doctoral supervisor Klaus Blaum and Sven Sturm.


Guang-Yu Guo

Guang-Yu Guo from the National Taiwan University, was awarded the status of Fellow in the American Physical Society, after they were nominated by their Division of Computational Physics in 2005, for "his contributions to our understanding of relativity-induced phenomena in magnetic solids and physical properties of materials including transition metal oxides and carbon nanotube structures, through first-principles electronic structure calculations."


Hellinger distance

In probability and statistics, the Hellinger distance (closely related to, although different from, the Bhattacharyya distance) is used to quantify the similarity between two probability distributions. It is a type of "f"-divergence. The Hellinger distance is defined in terms of the Hellinger integral, which was introduced by Ernst Hellinger in 1909.
Definition.
Measure theory.
To define the Hellinger distance in terms of measure theory, let "P" and "Q" denote two probability measures that are absolutely continuous with respect to a third probability measure λ. The square of the Hellinger distance between "P" and "Q" is defined as the quantity
Here, "dP" / "dλ" and "dQ" / "d"λ are the Radon–Nikodym derivatives of "P" and "Q" respectively. This definition does not depend on λ, so the Hellinger distance between "P" and "Q" does not change if λ is replaced with a different probability measure with respect to which both "P" and "Q" are absolutely continuous. For compactness, the above formula is often written as
Probability theory using Lebesgue measure.
To define the Hellinger distance in terms of elementary probability theory, we take λ to be the Lebesgue measure, so that "dP" / "dλ" and "dQ" / "d"λ are simply probability density functions. If we denote the densities as "f" and "g", respectively, the squared Hellinger distance can be expressed as a standard calculus integral
where the second form can be obtained by expanding the square and using the fact that the integral of a probability density over its domain equals 1.
The Hellinger distance "H"("P", "Q") satisfies the property (derivable from the Cauchy–Schwarz inequality)
Discrete distributions.
For two discrete probability distributions formula_5 and formula_6,
their Hellinger distance is defined as
which is directly related to the Euclidean norm of the difference of the square root vectors, i.e.
Also, formula_9
Properties.
The Hellinger distance forms a bounded metric on the space of probability distributions over a given probability space.
The maximum distance 1 is achieved when "P" assigns probability zero to every set to which "Q" assigns a positive probability, and vice versa.
Sometimes the factor formula_10 in front of the integral is omitted, in which case the Hellinger distance ranges from zero to the square root of two.
The Hellinger distance is related to the Bhattacharyya coefficient formula_11 as it can be defined as
Hellinger distances are used in the theory of sequential and asymptotic statistics.
The squared Hellinger distance between two normal distributions formula_13 and formula_14 is:
The squared Hellinger distance between two multivariate normal distributions formula_16 and formula_17 is
The squared Hellinger distance between two exponential distributions formula_19 and formula_20 is:
The squared Hellinger distance between two Weibull distributions formula_22 and formula_23 (where formula_24 is a common shape parameter and formula_25 are the scale parameters respectively):
The squared Hellinger distance between two Poisson distributions with rate parameters formula_27 and formula_28, so that formula_29 and formula_30, is:
The squared Hellinger distance between two Beta distributions formula_32 and formula_33 is:
where formula_35 is the Beta function.
Connection with total variation distance.
The Hellinger distance formula_36 and the total variation distance (or statistical distance) formula_37 are related as follows:
These inequalities follow immediately from the inequalities between the 1-norm and the 2-norm.


MSU Faculty of Physics

The Fizfak (Faculty of Physics) of Moscow State University is one of the most esteemed faculties of Moscow State University, widely regarded by students as one of the toughest faculties in the university. It was established in 1933. The current dean of the faculty - Nikolay Sysoev.


Joseph Laws McKibben

Joseph Laws McKibben (1912 – 2001) was an American physicist and engineer who worked with J. Robert Oppenheimer as a group leader on the Manhattan Project. He personally witnessed the Trinity test and flipped the switch that set off the atomic bomb at Trinity. McKibben, motivated by his daughter Karan's paralysed hands due to polio, also invented the Air Muscle in 1957.
He was born in 1912 in Missouri. He died in 2001 in Los Alamos, aged 89.


Stanley Mandelstam

Stanley Mandelstam (; 12 December 1928 – 23 June 2016) was an American theoretical physicist. He introduced the relativistically invariant Mandelstam variables into particle physics in 1958 as a convenient coordinate system for formulating his double dispersion relations. The double dispersion relations were a central tool in the bootstrap program which sought to formulate a consistent theory of infinitely many particle types of increasing spin.
Early life.
Mandelstam was born in Johannesburg, South Africa to a Jewish family.
Work.
Mandelstam, along with Tullio Regge, did the initial development of the Regge theory of strong interaction phenomenology. He reinterpreted the analytic growth rate of the scattering amplitude as a function of the cosine of the scattering angle as the power law for the falloff of scattering amplitudes at high energy. Along with the double dispersion relations, Regge theory allowed theorists to find sufficient analytic constraints on scattering amplitudes of bound states to formulate a theory in which there are infinitely many particle types, none of which are fundamental.
After Veneziano constructed the first tree-level scattering amplitude describing infinitely many particle types, what was recognized almost immediately as a string scattering amplitude, Mandelstam continued to make crucial contributions. He interpreted the Virasoro algebra discovered in consistency conditions as a geometrical symmetry of a world-sheet conformal field theory, formulating string theory in terms of two dimensional quantum field theory. He used the conformal invariance to calculate tree level string amplitudes on many worldsheet domains. Mandelstam was the first to explicitly construct the fermion scattering amplitudes in the Ramond and Neveu–Schwarz sectors of superstring theory, and later gave arguments for the finiteness of string perturbation theory.
In quantum field theory, Mandelstam and independently Sidney Coleman extended work of Tony Skyrme to show that the two dimensional quantum Sine-Gordon model is equivalently described by a Thirring model whose fermions are the kinks. He also demonstrated that the 4d N=4 supersymmetric gauge theory is power counting finite, proving that this theory is scale invariant to all orders of perturbation theory, the first example of a field theory where all the infinities in Feynman diagrams cancel.
Among his students at Berkeley are Joseph Polchinski, Michio Kaku, Charles Thorn and Hessamaddin Arfaei.
Stanley Mandelstam died in his Berkeley apartment in June, 2016.


Jonathan C. Knight

Jonathan C. Knight, (born 1964, in Lusaka) is a British physicist. He is the Pro Vice-Chancellor (Research) for the University of Bath where he has been Professor in the Department of Physics since 2000, and served as Head of Department. From 2005 to 2008, he was founding Director of the University's Centre for Photonics and Photonic Materials.
Education.
Knight studied at the University of Cape Town where he obtained his B.Sc (Hons), M.Sc. and PhD. His doctoral thesis was on whispering gallery mode microlasers. He did postdoctoral research at the École Normale Supérieure (Paris, 1994–1995) and at the Optoelectronics Research Centre (University of Southampton, 1995–1996).
Research.
Knight is interested in the behaviour of light in microstructured materials, and in the physics of optical fibres. Working with Russell and Tim Birks, he designed, fabricated and demonstrated a number of novel forms of optical fibre waveguide with previously unobtainable characteristics. This work has led to a range of outcomes including the commercialisation, of a new form of light source (supercontinuum), high power short pulse laser delivery through fibre, and applications in quantum and atomic physics. Belardi and Knight proposed the hollow-core "nested-ring" design for photonic fibres, at the beginning of 2014. Together with William Wadsworth, Knight co-created a new kind of laser capable of pulsed and continuous mid-infrared (IR) emission between 3.1 and 3.2 microns, a spectral range that has long presented a major challenge for laser developers.


Alexander V. Balatsky

Alexander V. Balatsky (born 19 October 1961) is a USSR-born American physicist. He is the professor of theoretical physics at NORDITA and University of Connecticut. He served as the founding director of the Institute for Materials Science (IMS) at Los Alamos National Laboratory in 2014-2017.
Biography.
Born in Pushkin, USSR he was educated in Russia, being made Master of Science at Moscow Physical-Technology Institute in 1984 and Doctor of Philosophy at the Landau Institute for Theoretical Physics in 1987. He moved to the United States in 1989 as a
postdoctoral fellow at the University of Illinois in 1989-1990 after which he was appointed a research assistant professor position at the University of Illinois at Urbana Champaign. He then moved to Los Alamos National Laboratory as an Oppenheimer Fellow. As an acting chief scientist and as a theory thrust leader he was actively involved in bringing up the Center of Integrated Nanotechnology (CINT) and building an active theory program at CINT.
In 2011 Balatsky was appointed as a professor of theoretical condensed matter physics at Nordita in Stockholm. In 2014 he returned to the US to become Director of the new Institute for Functional Materials at Los Alamos.
Work.
Balatsky is known for his contributions to the theory of High-temperature superconductivity, and mechanism of superconducting paring known as Spin Fluctuation Theory.
According to this theory, the pairing wave function of the cuprate HTS should have a dx2-y2 symmetry. The same spin fluctuation mechanism is likely responsible for the superconducting pairing in Heavy fermion superconductors and in Fe based superconductors.
Balatsky recently worked on anomalous mechanical properties of solid He4
as an alternative explanation of supersolidity seen in torsional oscillator experiments, on theory of Heavy Fermions, and on electronic and structural properties of DNA and Graphene hybrid structures
Balatsky and collaborators predicted the existence of the impurity induced resonances in d-wave superconductors that can serve as markers of unconventional superconductivity, and Impurity-induced states in conventional and unconventional superconductors.
He also proposed the notion of Dirac Materials as a unifying class of materials that exhibit Dirac like excitations.
Honors and awards.
He was elected as a Fellow of the American Physical Society in 2003, and Los Alamos Fellow in 2005. In Nov 2011, he was elected a fellow of the American Association for the Advancement of Science Fellow


Neutron triple-axis spectrometry

Triple-axis spectrometry (TAS, T also resolved as "three", S also resolved as "spectroscopy") is a technique used in inelastic neutron scattering. The instrument is referred to as triple-axis spectrometer (also called TAS). It allows measurement of the scattering function at any point in energy and momentum space physically accessible by the spectrometer.
History.
The triple-axis spectrometry method was first developed by Bertram Brockhouse at the National Research Experimental NRX reactor at the Chalk River Laboratories in Canada. The first results from the prototype triple-axis spectrometer were published in January 1955 and the first true triple-axis spectrometer was built in 1956. Bertram Brockhouse shared the 1994 Nobel prize for Physics for this development, which allowed elementary excitations, such as phonons and magnons, to be observed directly. The Nobel citation was "for pioneering contributions to the development of neutron scattering techniques for studies of condensed matter" and "for the development of neutron spectroscopy".


G. C. Danielson

Gordon Charles (G.C.) Danielson (October 28, 1912 - September 30, 1983) was a Distinguished Professor in Sciences and Humanities in 1964 at Iowa State University at Ames, Iowa.
His name was added to the Distinguished Professor Award Wall in Beardsher Hall.
A scholarship fund, the Gordon C. Danielson Fund was established in his name.
Danielson collaborated with Cornelius Lanczos to write the paper, "Some Improvements in Practical Fourier Analysis and their Application to X-ray Scattering from Liquids" (1942). The Danielson-Lanczos lemma, which appears in this paper, is the basis of the Cooley–Tukey FFT algorithm, an efficient algorithm for computing the discrete Fourier transform.
With L. D. Muhlstein he wrote "Effects of Ordering on the Transport Properties of Sodium Tungsten Bronze" (1967).


Andy Parker (physicist)

Michael Andrew Parker is a British physicist and is professor of high energy physics at the University of Cambridge. Parker attended Queen Elizabeth's Hospital, Bristol and in 1978 graduated with a Class II degree in Natural Sciences from the University of Oxford, which he followed with a PhD from University College London. Parker was appointed head of the Cavendish Laboratory in 2013.


Matsubara frequency

In thermal quantum field theory, the Matsubara frequency summation (named after Takeo Matsubara) is the summation over discrete imaginary frequencies. It takes the following form
where formula_2 is the inverse temperature and the frequencies formula_3 are usually taken from either of the following two sets (with formula_4):
The summation will converge if formula_7 tends to 0 in formula_8 limit in a manner faster than formula_9. The summation over bosonic frequencies is denoted as formula_10 (with formula_11), while that over fermionic frequencies is denoted as formula_12 (with formula_13). formula_14 is the statistical sign.
In addition to thermal quantum field theory, the Matsubara frequency summation method also plays an essential role in the diagrammatic approach to solid-state physics, namely, if one considers the diagrams at finite temperature.
Generally speaking, if at formula_15, a certain Feynman diagram is represented by an integral formula_16, at finite temperature it is given by the sum formula_17.
Summation formalism.
General formalism.
The trick to evaluate Matsubara frequency summation is to use a Matsubara weighting function "h""η"("z") that has simple poles located exactly at formula_18. The weighting functions in the boson case "η" = +1 and fermion case "η" = −1 differ. The choice of weighting function will be discussed later. With the weighting function, the summation can be replaced by a contour integral surrounding the imaginary axis.
As in Fig. 1, the weighting function generates poles (red crosses) on the imaginary axis. The contour integral picks up the residue of these poles, which is equivalent to the summation.
By deformation of the contour lines to enclose the poles of "g"("z") (the green cross in Fig. 2), the summation can be formally accomplished by summing the residue of "g"("z")"h""η"("z") over all poles of "g"("z"),
Note that a minus sign is produced, because the contour is deformed to enclose the poles in the clockwise direction, resulting in the negative residue.
Choice of Matsubara weighting function.
To produce simple poles on boson frequencies formula_21, either of the following two types of Matsubara weighting functions can be chosen
depending on which half plane the convergence is to be controlled in. formula_24 controls the convergence in the left half plane (Re "z" < 0), while formula_25 controls the convergence in the right half plane (Re "z" > 0). Here formula_26 is the Bose–Einstein distribution function.
The case is similar for fermion frequencies. There are also two types of Matsubara weighting functions that produce simple poles at formula_27
formula_30 controls the convergence in the left half plane (Re "z" < 0), while formula_31 controls the convergence in the right half plane (Re "z" > 0). Here formula_32 is the Fermi–Dirac distribution function.
In the application to Green's function calculation, "g"("z") always have the structure
which diverges in the left half plane given 0 < "τ" < "β". So as to control the convergence, the weighting function of the first type is always chosen formula_34. However, there is no need to control the convergence if the Matsubara summation does not diverge, in that case, any choice of the Matsubara weighting function will lead to identical results.
Table of Matsubara frequency summations.
The following table contains formula_35
for some simple rational functions "g"("z"). The symbol "η" = ±1 is the statistical sign.
[1] Since the summation does not converge, the result may differ upon different choice of the Matsubara weighting function.
[2] (1 ↔ 2) denotes the same expression as the before but with index 1 and 2 interchanged.
Applications in physics.
Zero temperature limit.
In this limit formula_36, the Matsubara frequency summation is equivalent to the integration of imaginary frequency over imaginary axis.
Some of the integrals do not converge. They should be regularized by introducing the frequency cutoff formula_38, and then subtracting the divergent part (formula_38-dependent) from the integral before taking the limit of formula_40. For example, the free energy is obtained by the integral of logarithm,
meaning that at zero temperature, the free energy simply relates to the internal energy below the chemical potential. Also the distribution function is obtained by the following integral
which shows step function behavior at zero temperature.
Green's function related.
Time domain.
Consider a function "G"("τ") defined on the imaginary time interval (0,"β"). It can be given in terms of Fourier series,
where the frequency only takes discrete values spaced by 2/"β".
The particular choice of frequency depends on the boundary condition of the function "G"("τ"). In physics, "G"("τ") stands for the imaginary time representation of Green's function
It satisfies the periodic boundary condition "G"("τ"+"β")="G"("τ") for a boson field. While for a fermion field the boundary condition is anti-periodic "G"("τ" + "β") = −"G"("τ").
Given the Green's function "G"("iω") in the frequency domain, its imaginary time representation "G"("τ") can be evaluated by Matsubara frequency summation. Depending on the boson or fermion frequencies that is to be summed over, the resulting "G"("τ") can be different. To distinguish, define
with
Note that "τ" is restricted in the principal interval (0,"β"). The boundary condition can be used to extend "G"("τ") out of the principal interval. Some frequently used results are concluded in the following table.
Operator switching effect.
The small imaginary time plays a critical role here. The order of the operators will change if the small imaginary time changes sign.
Distribution function.
The evaluation of distribution function becomes tricky because of the discontinuity of Green's function "G"("τ") at "τ" = 0. To evaluate the summation
both choices of the weighting function are acceptable, but the results are different. This can be understood if we push "G"("τ") away from "τ" = 0 a little bit, then to control the convergence, we must take formula_51 as the weighting function for formula_52, and formula_53 for formula_54.
Bosons
Fermions
Free energy.
Bosons
Fermions
Diagram evaluations.
Frequently encountered diagrams are evaluated here with the single mode setting. Multiple mode problems can be approached by spectral function integral.
Appendix: Properties of distribution functions.
Distribution functions.
The general notation formula_64 stands for either Bose ("η" = +1) or Fermi ("η" = −1) distribution function
If necessary, the specific notations "n"B and "n"F are used to indicate Bose and Fermi distribution functions respectively
Relation to hyperbolic functions.
The Bose distribution function is related to hyperbolic cotangent function by
The Fermi distribution function is related to hyperbolic tangent function by
Parity.
Both distribution functions do not have definite parity,
Another formula is in terms of the formula_70 function
However their derivatives have definite parity.
Bose–Fermi transmutation.
Bose and Fermi distribution functions transmute under a shift of the variable by the fermionic frequency,
However shifting by bosonic frequencies does not make any difference.
Derivatives.
First order.
In terms of product:
In the zero temperature limit:
The function "c""η".
Definition:
For Bose and Fermi type:
Relation to hyperbolic functions.
It is obvious that formula_90 is positive definite.
To avoid overflow in the numerical calculation, the tanh and coth functions are used
Low temperature limit.
For "a" = 0: formula_97
For "b" = 0: formula_98
In general,


Modular Neutron Array

The Modular Neutron Array (MoNA) is a large-area, high efficiency neutron detector that is used in basic research of rare isotopes at Michigan State University's National Superconducting Cyclotron Laboratory (NSCL), a nuclear physics research facility. It is specifically designed for detecting neutrons stemming from breakup reactions of fast fragmentation beams.
The MoNA Detector Array.
The Modular Neutron Array consists of 144 individual detector modules. Each module is based on a plastic scintillator measuring 10 cm by 10 cm by 200 cm. This scintillator bar is fitted with light guides on each end that direct the light into one photo-multiplier tube on each end. Each detector module is wrapped in a light-tight material, allowing the detector array to be arranged in different configurations.
In its original configuration, MoNA consisted of 9 vertical layers of 16 detectors stacked closely, having an active area of 2.0 m wide by 1.6 m tall. In its current arrangement (depicted in the adjacent image), it is stacked in four separate sections of 2, 2, 2, and 3 layers each, respectively, separated by spaces ranging from 0.5 to 0.8 meters. It measures both the position and time of neutron events with multiple-hit capability. The energy of a neutron is based on a time-of-flight measurement. This information together with the detected position of the neutron is used to construct the momentum vector of the neutrons.
The detection efficiency of MoNA is maximized for the high-beam velocities that are available at the NSCL's Coupled Cyclotron Facility (CCF). For neutrons ranging from 50 to 250 MeV in energy, it is designed to have an efficiency of up to 70% and expands the possible coincidence experiments with neutrons to measurements which were previously not feasible. The detector is used in combination with the Sweeper magnet and its focal plane detectors for charged particles. In addition, MoNA’s modular design allows it to be transported between experimental vaults and thus to be used in combination with the Sweeper magnet installed at the S800 magnet spectrograph. Due to its high-energy detection efficiency, this detector will be well suited for experiments with fast fragmentation beams at the proposed ISF.
History.
When the NSCL upgraded their capabilities to the Coupled Cyclotron facility, a Florida State University/Michigan State University consortium built the Sweeper magnet to be used with two existing neutron walls to perform neutron–fragment coincidence experiments. The neutron walls were originally built for lower beam energies and had only an efficiency of about 12% for the neutron energies expected from the CCF. During the 2000 NSCL users meeting, a working group realized the opportunity to significantly enhance the efficiency with an array of more layers using plastic scintillator detectors.
Several NSCL users from undergraduate schools were present at the working group meeting and they suggested that the modular nature and simple construction would offer great opportunities to involve undergraduate students.
In the spring of 2001, the idea evolved into several MRI proposals submitted by 10 different institutions, most of them undergraduate schools. Physicists at these ten academic institutions formed the MoNA Collaboration:
The proposals were funded by the NSF in the summer of 2001. Following the detailed design, the first modules of the detector array were delivered in the summer of 2002. During the following year all modules were assembled and tested by undergraduate students at their school, and finally added to form the complete array at the NSCL.
The MoNA collaboration continued after the initial phase of construction and commissioning was concluded [MoNA], and is now using the detector array for experiments, giving a large number of undergraduate students from all collaborating schools the opportunity to take part in cutting-edge nuclear physics experiments at one of the world’s leading rare-isotope facilities. The research at the undergraduate institutions is funded by the NSF through several RUI (Research at Undergraduate Institutions) grants.
The MoNA Collaboration.
The MoNA Collaboration currently includes physicists from eleven colleges and universities. The project is funded by the National Science Foundation.
The members of the collaboration are:
The collaboration is committed to involving undergraduates in significant parts of the experimental program at the MoNA facility. Most of the collaboration member institutions are primarily undergraduate schools. Undergraduates helped construct and test MoNA and continue to participate in experiments during runs and through data analysis. It also created intensive summer sessions designed for undergraduates, encouraging students to participate in all phases of experiments, holding several meetings a year that include undergraduate participants, and employing information technology to bring the distant undergraduate students together.


Sawyer motor

A Sawyer motor or planar motor is a type of linear electric motor with a forcer capable of moving in two dimensions, riding on a stator which is a large flat—or nearly flat—plate. Sawyer motors have been used in positioning stages and pen plotters.
This class of motors is named for Bruce Sawyer, who invented it in 1968.
The US-patent was submitted 1966 and granted 1968.
References.
5. Linear magnetic drive system (1973-05-22) U.S Patent 3,735,231A, B Sawyer


Seibert Q. Duntley

Seibert Quimby Duntley was born in Bushnell, Illinois on October 2, 1911. He received an SB in physics from Massachusetts Institute of Technology in 1933. Duntley received an MS degree from California Institute of Technology in 1935 and an Sc.D. in physics from MIT in 1939. While at MIT, Duntley met and worked with Karl Taylor Compton, Harold Eugene Edgerton, and many other prominent physicists. Duntley's primary interest was in applied physics particularly the optics of turbid media.
He started the Visibility Laboratory at the Massachusetts Institute of Technology in 1939/40. It was the brainchild of Duntley and MIT physics chair Dr. Arthur C. Hardy. It was focused on applying optics to such problems as camouflage, misdirection of aerial bombardment, target location, visibility of submerged objects at sea. In 1952, Roger Revelle and Quimby Duntley agreed that the laboratory would become part of the Scripps Institution of Oceanography in San Diego, and the U.S. Navy Bureau of Ships agreed to pay for the move. The work of the laboratory centered on the transmission of visible light through the atmosphere and water and the related problems of image formation and recognition. The nature of much of the research required measurements of the optical properties of the ocean or atmosphere for which no instruments existed. As a result of these requirements, many unique and very specialized instruments were developed by the laboratory, many of which were based on concepts or optical designs devised by Duntley. He earned the academic rank of Professor in 1966 and taught at Scripps Institution of Oceanography and at the Department of Applied Physics and Information Science (APIS) at UCSD until his retirement.
Duntley was an active member of many professional associations, particularly the Optical Society of America and Sigma Xi. He was president of the Optical Society of America in 1965. He was Chairman of the Representatives of the Optical Society on the U.S. National Committee of the International Commission on Illumination. During the 1960s he was a member of the Armed Forces-National Research Council Committee on Vision. He was a participant in the 1971 JASON Laser Summer Study. He chaired the David Richardson Medal Committee of the Optical Society of America from 1972 to 1975. He received many awards, including the Army-Navy Certificate of Appreciation and, in 1961, the Frederic Ives Medal, the highest award of the Optical Society of America, "recognizing overall distinction in optics." Quimby Duntley died in La Jolla on October 22, 1999.


Tony Maxworthy

Tony Maxworthy (born in May 1933 in Ealing; died 8 March 2013) was a British-American noted for work in geophysical fluid dynamics. He had won the Fluid Dynamics Prize, the Otto Laporte Award, and others.
Maxworthy obtained his bachelor's degree from Imperial College London in 1954 and the Masters from Princeton University in 1955. For his PhD, he joined Harvard University and worked under the supervision of Howard Wilson Emmons, getting his degree in 1960. From 1960 to 1967, he worked in the Jet Propulsion Laboratory and then joined University of Southern California, staying there until his death in 2013.


Scalar (physics)

In physics, a scalar or scalar quantity is a quantity that can be described by a single element of a number field, such as a real number, often accompanied by units of measurement, as in "10cm". This is in contrast to vectors, tensors, etc. which are described by several numbers that characterize their magnitude, direction, and so on.
The concept of a scalar in physics is essentially the same as a scalar in mathematics. Formally, a scalar is unchanged by coordinate system transformations. In classical theories, like Newtonian mechanics, this means that rotations or reflections preserve scalars, while in relativistic theories, Lorentz transformations or space-time translations preserve scalars.
Scalar field.
Since scalars mostly may be treated as special cases of multi-dimensional quantities such as vectors and tensors, "physical scalar fields" might be regarded as a special case of more general fields, like vector fields, spinor fields, and tensor fields.
Physical quantity.
A physical quantity of scalar is expressed by a numerical value and a physical unit, not merely a number. Its quantity may be regarded as the product of the number and the unit (e.g. for distance, 1 km is the same as 1,000 m). Thus, following the example of distance, the quantity does not depend on the length of the base vectors of the coordinate system. Also, other changes of the coordinate system may affect the formula for computing the scalar (for example, the Euclidean formula for distance in terms of coordinates relies on the basis being orthonormal), but not the scalar itself. In this sense, physical distance deviates from the definition of metric in not being just a real number; however, it satisfies all other properties. The same applies for other physical quantities which are not dimensionless.
Non-relativistic scalars.
Temperature.
An example of a scalar quantity is temperature: The temperature at a given point is a single number. Velocity, on the other hand, is a vector quantity.
Other examples.
Some examples of scalar quantities in physics are mass, charge, volume, time, speed, and electric potential at a point inside a medium. The distance between two points in three-dimensional space is a scalar, but the direction from one of those points to the other is not, since describing a direction requires two physical quantities such as the angle on the horizontal plane and the angle away from that plane. Force cannot be described using a scalar, since force has both direction and magnitude; however, the magnitude of a force alone can be described with a scalar, for instance the gravitational force acting on a particle is not a scalar, but its magnitude is. The speed of an object is a scalar (e.g. 180 km/h), while its velocity is not (e.g. 108 km/h northward and 144 km/h westward).
Some other examples of scalar quantities in Newtonian mechanics are electric charge and charge density.
Relativistic scalars.
In the theory of relativity, one considers changes of coordinate systems that trade space for time. As a consequence, several physical quantities that are scalars in "classical" (non-relativistic) physics need to be combined with other quantities and treated as four-vectors or tensors. For example, the charge density at a point in a medium, which is a scalar in classical physics, must be combined with the local current density (a 3-vector) to comprise a relativistic 4-vector. Similarly, energy density must be combined with momentum density and pressure into the stress–energy tensor.
Examples of scalar quantities in relativity include electric charge, spacetime interval (e.g., proper time and proper length), and invariant mass.


Jianming Qian

Jianming Qian from the University of Michigan, was awarded the status of Fellow in the American Physical Society, after he was nominated by their Division of Particles and Fields in 2009, for outstanding contributions and leadership in the analysis of high-energy particle interactions at CERN and at Fermilab, with especially noteworthy participation in the D-Zero experiment leading to the recent discovery of two new baryons containing b-qu.


Paolo Radaelli

Paolo Giuseppe Radaelli, FInstP (born 11 October 1961) is an Italian physicist and academic. He is the Dr Lee's Professor of Experimental Philosophy (Physics) at the University of Oxford and a Professorial Fellow of Wadham College, Oxford.
Biography.
Radaelli obtained a Laurea degree "Summa cum Laude" in 1986 from University of Milan (his thesis supervisor was Pino Marchesini). As part of the mandatory Italian National Service, he served for one year in the 28th Infantry Battalion "Pavia" as a drill instructor, leaving with the rank of corporal major. Between 1988 and 1989, he worked as a Research Associate at the ITM institute of the National Research Council (Italy) in the field of High-temperature superconductivity. In 1989, he was awarded a travel scholarship by Pirelli Cavi e Sistemi and moved to the Illinois Institute of Technology (Chicago) where he later completed a PhD under the academic supervision of Carlo Segre, and working in close collaboration with James D. Jorgensen and David Hinks at Argonne National Laboratory. After a post-doc in Jorgensen's group between 1992 and 1993, he moved to Grenoble, first as a post-doc with Massimo Marezio at the Laboratories de Cristallographie of the Centre national de la recherche scientifique, then as a scientist at the Institut Laue–Langevin. In 1998, he became Instrument Scientists and later Crystallography Group Leader at the ISIS neutron source at the Rutherford Appleton Laboratory in Didcot, England. Since 2008, he is the Dr Lee's Professor of Experimental Philosophy (Physics) at the University of Oxford, and he is also a Professorial Fellow of Wadham College, Oxford. In 2017 he was appointed a Knight of the Order of the Star of Italy.


Vladimir Teplyakov

Vladimir Aleksandrovich Teplyakov () (6 November 1925 – 10 December 2009) was a Russian experimental physicist known for his work on particle accelerators. Together with I.M. Kapchinsky, he invented the principle of the radio-frequency quadrupole (RFQ), which revolutionized the acceleration of low-energy charged particle beams.
Biography.
Teplyakov was born in Tambov, Russia. At the age of 17, in January 1943, he was drafted into the Red Army to fight in the Second World War, serving in the 3rd Ukrainian Front. He participated in a number of operations in Right-bank Ukraine, Moldavia and Eastern Europe and was awarded combat orders and medals.
After the war, he graduated from the All-Union Correspondence Polytechnic Institute in Moscow and joined the team of scientists at the Institute of Chemical Physics of the Soviet Academy of Sciences who worked on the large particle accelerator for conversion of uranium-238 into weapons-grade plutonium-239. From 1959 to 1966 he worked at Chelyabinsk-70 to develop a high-current proton linear particle accelerator ("linac") for controlled thermonuclear fusion. In the mid 1960s, together with G. M. Anisimov, Teplyakov conceived the idea of focusing the charged particle beams by the radio-frequency (RF) accelerating electromagnetic field rather than by solenoid magnets. This work continued at the Institute for High Energy Physics (IHEP) in Protvino, where his group moved in 1966 to build the I-100, a 100 MeV Alvarez drift-tube linac, which was an injector to the U-70, a 70 GeV proton synchrotron, the world's largest particle accelerator at that time.
By the late 1960s, Teplyakov and I. M. Kapchinsky developed the concept of the radio-frequency quadrupole (RFQ), where accelerating gaps are supplemented with spacer electrodes charged under an intermediate potential. Such a focusing system resulted in a noticeable upgrade in performance and a significant decrease of the dimensions of the drift tubes. Teplyakov subsequently developed several RFQ drift-tube structures and RF cavities to drive them. The URAL-30 proton linac was commissioned in 1977. It applies a through front-to-end RFQ-focusing up to the top energy of 30 MeV. Since 1985 URAL-30 routinely operates as an injector to booster proton synchrotron of IHEP.
Teplyakov was the author of more than 100 inventions and scientific papers, and was the co-author of the book "Linear Accelerators of Ions".
Honours and awards.
For the invention of the RFQ, Teplyakov was awarded the 1988 Lenin Prize (together with Kapchinsky) and the U.S. Particle Accelerator School Prize for Achievement in Accelerator Physics and Technology. In 2006, The European Physical Society awarded him the prize "for outstanding work in the accelerator field". Teplyakov received the highest decorations bestowed by the Soviet Union, the Order of Lenin and the Order of the October Revolution. He was one of the first to receive the title "Veteran of Nuclear Industry" and also received the title "Honored Worker of Science and Technology of Russian Federation". Teplyakov died on 10 December 2009.


William F. Brinkman

William Frank Brinkman is an American physicist who served as president of the American Physical Society (2002) and was the head of the Office of Science at the United States Department of Energy (2009-2013). He was elected to the National Academy of Sciences in 1984, and won the George E. Pake Prize in 1994. He was elected as a member of the American Academy of Arts and Sciences in 1992.
Brinkman was born on July 20, 1938, in Washington, Missouri. He received his bachelor's degree (1960) and PhD (1965) in physics from the University of Missouri.
Brinkman joined Bell Labs in 1966, working in the physics research laboratory. From 1984–87, he served as vice president of research at Sandia National Laboratories. In 1987 he became executive director of the physics research division at Bell Labs.
Brinkman joined Princeton University in 2001, where he continued his condensed matter physics research. In 2009, he was appointed as director of the Office of Science in the U.S. Department of Energy, where he served until 2013.