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Topic Review
Solar Physics
Solar physics is the branch of astrophysics that specializes in the study of the Sun. It deals with detailed measurements that are possible only for our closest star. It intersects with many disciplines of pure physics, astrophysics, and computer science, including fluid dynamics, plasma physics including magnetohydrodynamics, seismology, particle physics, atomic physics, nuclear physics, stellar evolution, space physics, spectroscopy, radiative transfer, applied optics, signal processing, computer vision, computational physics, stellar physics and solar astronomy. Because the Sun is uniquely situated for close-range observing (other stars cannot be resolved with anything like the spatial or temporal resolution that the Sun can), there is a split between the related discipline of observational astrophysics (of distant stars) and observational solar physics. The study of solar physics is also important as it provides a "physical laboratory" for the study of plasma physics.
  • 886
  • 29 Sep 2022
Topic Review
Exploration Mission-1
Exploration Mission-1 or EM-1 (previously known as Space Launch System 1 or SLS-1) is the uncrewed first planned flight of the Space Launch System and the second flight of the Orion Multi-Purpose Crew Vehicle. The launch is planned for June 2020 from Launch Complex 39B at the Kennedy Space Center. The Orion spacecraft will spend approximately 3 weeks in space, including 6 days in a retrograde orbit around the Moon. It is planned to be followed by Exploration Mission 2 in 2023.
  • 661
  • 28 Sep 2022
Topic Review
Magnitude
In astronomy, magnitude is a unitless measure of the brightness of an object in a defined passband, often in the visible or infrared spectrum, but sometimes across all wavelengths. An imprecise but systematic determination of the magnitude of objects was introduced in ancient times by Hipparchus. The scale is logarithmic and defined such that a magnitude 1 star is exactly 100 times brighter than a magnitude 6 star. Thus each step of one magnitude is [math]\displaystyle{ \sqrt{100} \approx 2.512 }[/math] times brighter than the next faintest. The brighter an object appears, the lower the value of its magnitude, with the brightest objects reaching negative values. Astronomers use two different definitions of magnitude: apparent magnitude and absolute magnitude. The apparent magnitude (m) is the brightness of an object as it appears in the night sky from Earth. Apparent magnitude depends on an object's intrinsic luminosity, its distance, and the extinction reducing its brightness. The absolute magnitude (M) describes the intrinsic luminosity emitted by an object and is defined to be equal to the apparent magnitude that the object would have if it were placed at a certain distance from Earth, 10 parsecs for stars. A more complex definition of absolute magnitude is used for planets and small Solar System bodies, based on its brightness at one astronomical unit from the observer and the Sun. The Sun has an apparent magnitude of −27 and Sirius, the brightest visible star in the night sky, −1.46. Venus at its brightest is -5. The International Space Station (ISS) sometimes reaches a magnitude of −6.
  • 1.5K
  • 28 Sep 2022
Topic Review
Technicolor
Technicolor theories are models of physics beyond the Standard Model that address electroweak gauge symmetry breaking, the mechanism through which W and Z bosons acquire masses. Early technicolor theories were modelled on quantum chromodynamics (QCD), the "color" theory of the strong nuclear force, which inspired their name. Instead of introducing elementary Higgs bosons to explain observed phenomena, technicolor models were introduced to dynamically generate masses for the W and Z bosons through new gauge interactions. Although asymptotically free at very high energies, these interactions must become strong and confining (and hence unobservable) at lower energies that have been experimentally probed. This dynamical approach is natural and avoids issues of Quantum triviality and the hierarchy problem of the Standard Model. However, since the Higgs boson discovery at the CERN LHC in 2012, the original models are largely ruled out. Nonetheless, it remains a possibility that the Higgs boson is a composite state. In order to produce quark and lepton masses, technicolor or composite Higgs models have to be "extended" by additional gauge interactions. Particularly when modelled on QCD, extended technicolor was challenged by experimental constraints on flavor-changing neutral current and precision electroweak measurements. The specific extensions of particle dynamics for technicolor or composite Higgs bosons are unknown. Much technicolor research focuses on exploring strongly interacting gauge theories other than QCD, in order to evade some of these challenges. A particularly active framework is "walking" technicolor, which exhibits nearly conformal behavior caused by an infrared fixed point with strength just above that necessary for spontaneous chiral symmetry breaking. Whether walking can occur and lead to agreement with precision electroweak measurements is being studied through non-perturbative lattice simulations. Experiments at the Large Hadron Collider have discovered the mechanism responsible for electroweak symmetry breaking, i.e., the Higgs boson, with mass approximately 125 GeV/c2; such a particle is not generically predicted by technicolor models. However, the Higgs boson may be a composite state, e.g., built of top and anti-top quarks as in the Bardeen–Hill–Lindner theory. Composite Higgs models are generally solved by the top quark infrared fixed point, and may require a new dynamics at extremely high energies such as topcolor.
  • 719
  • 28 Sep 2022
Topic Review
Holeum
Holeums are hypothetical stable, quantized gravitational bound states of primordial or micro black holes. Holeums were proposed by L. K. Chavda and Abhijit Chavda in 2002. They have all the properties associated with cold dark matter. Holeums are not black holes, even though they are made up of black holes.
  • 675
  • 28 Sep 2022
Topic Review
Wave-particle Duality Relation
The Wave–particle duality relation, often loosely referred to as the Englert–Greenberger–Yasin duality relation, or the Englert–Greenberger relation, relates the visibility, [math]\displaystyle{ V }[/math], of interference fringes with the definiteness, or distinguishability, [math]\displaystyle{ D }[/math], of the photons' paths in quantum optics. As an inequality: Although it is treated as a single relation, it actually involves two separate relations, which mathematically look very similar. The first relation, derived by Greenberger and Yasin in 1988, is expressed as [math]\displaystyle{ P^2+ V^2\le 1 \, }[/math]. It was later extended by Jaeger, Shimony, and Vaidman in 1995. This relation involves correctly guessing which of the two paths the particle would have taken, based on the initial preparation. Here [math]\displaystyle{ P }[/math] can be called the predictability. An year later Englert, in 1996, derived a related relation which dealt with experimentally acquiring knowledge of the two paths using an apparatus, as opposed to predicting the path based on initial preparation This relation is [math]\displaystyle{ D^2+ V^2\le 1 \, }[/math]. Here [math]\displaystyle{ D }[/math] is called the distinguishability. The significance of the relations is that they express quantitatively the complementarity of wave and particle viewpoints in double slit experiments. The complementarity principle in quantum mechanics, formulated by Niels Bohr, says that the wave and particle aspects of quantum objects cannot be observed at the same time. The wave–particle duality relations makes Bohr's statement more quantitative – an experiment can yield partial information about the wave and particle aspects of a photon simultaneously, but the more information a particular experiment gives about one, the less it will give about the other. The predictability [math]\displaystyle{ P }[/math] which expresses the degree of probability with which path of the particle can be correctly guessed, and the distinguishability [math]\displaystyle{ D }[/math] which is the degree to which one can experimentally acquire information about the path of the particle, are measures of the particle information, while the visibility of the fringes [math]\displaystyle{ V }[/math] is a measure of the wave information. The relations shows that they are inversely related, as one goes up, the other goes down.
  • 433
  • 27 Sep 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.
  • 942
  • 27 Sep 2022
Topic Review
Triboelectric Nanogenerator for Sports Applications
Progress in science and technology drives the continuous innovation of energy collection and utilization. In the field of sports, the information collection and analysis based on Internet of things have attracted particular attention. On this basis, it is considered that the stability of devices, the universality of materials, and the scientificity of application of the TENG in the future need to be improved. There is a direction for further upgrading energy collection technology to promote the high-quality development of human mechanical energy sensing in the field of sports.
  • 551
  • 06 Sep 2022
Biography
Boris Stoyanov
Boris Stoyanov is a theoretical physicist working on Membrane Theory, Supergravity and Superstring Theory. He is the Principal and Permanent Member of SUGRA INSTITUTE, Executive Director of BRANE HEPLAB and the Giordano Bruno Professor of Membrane Theory at DARK MODULI INSTITUTE. Boris Stoyanov is a relatively young theoretical physicist dealing with the exclusive theories of supergravity, super
  • 2.0K
  • 01 Sep 2022
Topic Review
Coconut Palm
The price of traditional sources of nutrients used in animal feed rations is increasing steeply in developed countries due to their scarcity, high demand from humans for the same food items, and expensive costs of raw materials. Thus, one of the alternative sources is coconut parts or coconut as a whole fruit. Coconut is known as the ‘tree of abundance’, ‘tree of heaven’, and ‘tree of life’ owing to its numerous uses, becoming a very important tree in tropical areas for its provision of food, employment, and business opportunities to millions of people. Coconut contains a rich profile of macro and micronutrients that vary depending on the parts and how they are used. It is frequently chosen as an alternative source of protein and fiber. Its uses as an antibacterial agent, immunomodulant, and antioxidant further increase its importance. Using coconut oil in ruminant feed helps to minimize methane gas emissions by 18–30%, and to reduce dry matter intake up to 4.2 kg/d. The aquaculture sectors also use coconut palm as an alternative source because it significantly improves the digestion, growth, lipid metabolism, health, and antioxidative responses. However, coconut is not widely used in poultry diets although it has adequate amount of protein and carbohydrate due to anti-nutritional factors such cellulose (13%), galactomannan (61%), and mannan (26%). 
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  • 31 Aug 2022
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