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Topic Review
K-Theory
In string theory, K-theory classification refers to a conjectured application of K-theory (in abstract algebra and algebraic topology) to superstrings, to classify the allowed Ramond–Ramond field strengths as well as the charges of stable D-branes. In condensed matter physics K-theory has also found important applications, specially in the topological classification of topological insulators, superconductors and stable Fermi surfaces ((Kitaev 2009), (Horava 2005)).
  • 414
  • 30 Nov 2022
Topic Review
Jyotisha
Jyotisha (Sanskrit: ज्योतिष, IAST: Jyotiṣa), now the term for traditional Hindu astrology, historically was the branch of knowledge dedicated to the observation of astronomical bodies in order to keep the right time for the Vedic sacrifices. It is one of the six Vedangas, or ancillary science connected with the Vedas that developed . This field of study was concerned with fixing the days and hours of Vedic rituals. Hindu astrology from the 3rd century BCE was greatly influenced by Greek tradition,. But the concept of Vedanga predates Greek contact, and there have also been later independent developments. Hindu astrology as it stands today is inherently a study of karma, which gives it a very different foundation compared to Greek astrology. In addition to this, the predictive techniques such as Dashas (planetary and sign-based time periods), Vargas (harmonic divisions of the horoscope) are not that evolved in Greek astrology.
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  • 27 Sep 2022
Biography
Jürgen Kurths
Jürgen Kurths (born 11 March 1953 in Arendsee/Altmark) is a German physicist and mathematician. He is a chair of the research department Complexity Sciences of the Potsdam Institute for Climate Impact Research, a Professor of Nonlinear Dynamics at the Institute of Physics at the Humboldt University, Berlin, and a 6th-century chair for Complex Systems Biology at the Institute for Complex Systems
  • 402
  • 12 Dec 2022
Biography
Julius Edgar Lilienfeld
Julius Edgar Lilienfeld (April 18, 1882 – August 28, 1963) was a Jewish Austro-Hungarian-born German-American physicist and electronic engineer, credited with the first patents on the field-effect transistor (FET) (1925) and electrolytic capacitor (1931). Because of his failure to publish articles in learned journals and because high-purity semiconductor materials were not available yet, his
  • 1.1K
  • 10 Nov 2022
Biography
Jules Aarons
Jules Aarons (October 3, 1921 – November 21, 2008) was an American space physicist known for his study of radio-wave propagation, and a photographer known for his street photography in Boston. Aarons was born in the Bronx, NY, where his father worked in the garment industry. He graduated from the City College of New York in 1942. During World War II he served in the Army Signal Corps. He st
  • 340
  • 14 Nov 2022
Biography
Juan Gualterio Roederer
Juan G. Roederer is a professor of physics emeritus at the University of Alaska Fairbanks (UAF). His research fields are space physics, psychoacoustics, science policy and information theory. He conducted pioneering research on solar cosmic rays, on the theory of earth’s radiation belts, neural networks for pitch processing, and currently on the foundations of information theory. He is also an
  • 317
  • 06 Dec 2022
Topic Review
Jpsi Meson
The J/ψ (J/psi) meson /ˈdʒeɪ ˈsaɪ ˈmiːzɒn/ or psion is a subatomic particle, a flavor-neutral meson consisting of a charm quark and a charm antiquark. Mesons formed by a bound state of a charm quark and a charm anti-quark are generally known as "charmonium". The J/ψ is the most common form of charmonium, due to its spin of 1 and its low rest mass. The J/ψ has a rest mass of 3.0969 GeV/c2, just above that of the ηc (2.9836 GeV/c2), and a mean lifetime of 7.2×10−21 s. This lifetime was about a thousand times longer than expected. Its discovery was made independently by two research groups, one at the Stanford Linear Accelerator Center, headed by Burton Richter, and one at the Brookhaven National Laboratory, headed by Samuel Ting of MIT. They discovered they had actually found the same particle, and both announced their discoveries on 11 November 1974. The importance of this discovery is highlighted by the fact that the subsequent, rapid changes in high-energy physics at the time have become collectively known as the "November Revolution". Richter and Ting were awarded the 1976 Nobel Prize in Physics.
  • 500
  • 29 Nov 2022
Topic Review
JPL Mars Helicopter Scout
The Mars Helicopter Scout (MHS) is a planned robotic helicopter that will test the technology to scout interesting targets for study on Mars, and help plan the best driving route for future Mars rovers. The small drone helicopter will be deployed in 2021 from the planned Mars 2020 rover. It is expected to fly up to five times during its 30-day test campaign, early in the rover's mission, as it is primarily a technology demonstration. Each flight will take no more than 3 minutes, at altitudes ranging from 3 m to 10 m above the ground, but it could potentially cover a maximum distance of about 600 m (2,000 ft) per flight. It will use autonomous control and communicate with the Mars 2020 rover directly after each landing. If it works as expected, NASA will be able to build on the design for future Mars missions. MiMi Aung is the project lead. Other team members are AeroVironment Inc., NASA Ames Research Center, and NASA Langley Research Center.
  • 314
  • 24 Nov 2022
Biography
Joseph Larmor
Sir Joseph Larmor FRS FRSE DCL LLD[1] (11 July 1857 – 19 May 1942) was an Irish[2] physicist and mathematician who made innovations in the understanding of electricity, dynamics, thermodynamics, and the electron theory of matter. His most influential work was Aether and Matter, a theoretical physics book published in 1900. He was born in Magheragall in County Antrim the son of Hugh Larmor,
  • 454
  • 02 Dec 2022
Biography
John Holdren
John Paul Holdren (Sewickley, Pennsylvania, March 1, 1944) is an American scientist. He served as the senior advisor to President Barack Obama on science and technology issues through his roles as Assistant to the President for Science and Technology, Director of the White House Office of Science and Technology Policy, and Co-Chair of the President’s Council of Advisors on Science and Technolo
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  • 30 Nov 2022
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