Scientific News

Articles across mathematics, physics, chemistry, biology, and astronomy.

• Science

  Speed prior

  The speed prior is a complexity measure similar to Kolmogorov complexity, except that it is based on computation speed as well as program length. The speed prior complexity of a program is its size in bits plus the logarithm of the maximum time we are willing to run it to get a prediction. When compared to traditional measures, use of the Speed. Prior has the disadvantage of leading to less optima

  8/25/2026

• Science

  Speedup theorem

  In computational complexity theory, a speedup theorem is a theorem that for any algorithm (of a certain class) demonstrates the existence of a more efficient algorithm solving the same problem. Examples: Linear speedup theorem, that the space and time requirements of a Turing machine solving a decision problem can be reduced by a multiplicative constant factor. Blum's speedup theorem, which prov

  8/25/2026

• Science

  Spin tensor

  In mathematics, mathematical physics, and theoretical physics, the spin tensor is a quantity used to describe the rotational motion of particles in spacetime. The spin tensor has application in general relativity and special relativity, as well as quantum mechanics, relativistic quantum mechanics, and quantum field theory. The special Euclidean group SE(d) of direct isometries is generated by tra

  8/25/2026

• Science

  Spherical multipole moments

  In physics, spherical multipole moments are the coefficients in a series expansion of a potential that varies inversely with the distance R to a source, i.e., as ⁠ 1 R . {\displaystyle {\tfrac {1}{R}}.} ⁠ Examples of such potentials are the electric potential, the

  8/25/2026

• Science

  Spherical basis

  In pure and applied mathematics, particularly quantum mechanics and computer graphics and their applications, a spherical basis is the basis used to express spherical tensors. The spherical basis closely relates to the description of angular momentum in quantum mechanics and spherical harmonic functions. While spherical polar coordinates are one orthogonal coordinate system for expressing vectors

  8/25/2026

• Science

  Spin pumping

  Spin pumping is the dynamical generation of pure spin current by the coherent precession of magnetic moments, which can efficiently inject spin from a magnetic material into an adjacent non-magnetic material. The non-magnetic material usually hosts the spin Hall effect that can convert the injected spin current into a charge voltage easy to detect. A spin pumping experiment typically requires elec

  8/25/2026

• Science

  Spinning band distillation

  Spinning band distillation is a technique used to separate liquid mixtures which are similar in boiling points. When liquids with similar boiling points are distilled, the vapors are mixtures, and not pure compounds. Fractionating columns help separate the mixture by allowing the mixed vapors to cool, condense, and vaporize again in accordance with Raoult's law. With each condensation-vaporization

  8/25/2026

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  Science

  Spin echo

  In magnetic resonance, a spin echo or Hahn echo is the refocusing of spin magnetisation by a pulse of resonant electromagnetic radiation. Modern nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) make use of this effect. The NMR signal observed following an initial excitation pulse decays with time due to both spin relaxation and any inhomogeneous effects which cause spins in th

  8/25/2026

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  Science

  Spider (polarimeter)

  Spider is a balloon-borne experiment designed to search for primordial gravitational waves imprinted on the cosmic microwave background (CMB). Measuring the strength of this signal puts limits on inflationary theory. The Spider instrument consists of six half degree-resolution telescopes cooled to liquid Helium temperature (4 K) which observe at frequencies of 100 GHz, 150 GHz, and 280 GHz (corr

  8/25/2026

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  Science

  Spindrift

  Spindrift (rarely spoondrift) is the spray blown from cresting waves during a gale. This spray, which "drifts" in the direction of the gale, is one of the characteristics of a wind speed of 8 Beaufort and higher at sea. In Greek and Roman mythology, Leucothea was the goddess of spindrift.

  8/25/2026

• Science

  Spin-exchange

  In quantum mechanics, spin-exchange is an interaction process between two particles mediated by an exchange interaction. It preserves total angular momentum of the system but may allow other aspects of the system to change. When two spin-polarized atoms in their ground state experience a spin-exchange collision, the total spin of the atoms is preserved yet the orientation of the individual spins m

  8/25/2026

• Science

  Spice (oceanography)

  Spice, spiciness, or spicity, symbol τ, is a term in oceanography referring to variations in the temperature and salinity of seawater over space or time, whose combined effects leave the water's density unchanged. For a given spice, any change in temperature is offset by a change in salinity to maintain unchanged density. An increase in temperature decreases density, but an increase in salinity

  8/25/2026

• Science

  Spin stiffness

  The spin stiffness or spin rigidity is a constant which represents the change in the ground state energy of a spin system as a result of introducing a slow in-plane twist of the spins. The importance of this constant is in its use as an indicator of quantum phase transitions—specifically in models with metal-insulator transitions such as Mott insulators. It is also related to other topological inv

  8/25/2026

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  Science

  Spin crossover

  Spin crossover (SCO) is a phenomenon that occurs in some metal complexes wherein the spin state of the complex changes due to an external stimulus. The stimuli can include temperature, pressure or radiation. Spin crossover is referred to as spin transition if takes place suddenly,or spin equilibrium, when is gradual. However, this terminology is not strict, the "cross-over" and "transition" being

  8/25/2026

• Science

  Spin engineering

  Spin engineering describes the control and manipulation of quantum spin systems to develop devices and materials. This includes the use of the spin degrees of freedom as a probe for spin based phenomena. Because of the basic importance of quantum spin for physical and chemical processes, spin engineering is relevant for a wide range of scientific and technological applications. Current examples

  8/25/2026

• Science

  Spin geometry

  In mathematics, spin geometry is the area of differential geometry and topology where objects like spin manifolds and Dirac operators, and the various associated index theorems have come to play a fundamental role both in mathematics and in mathematical physics. An important generalisation is the theory of symplectic Dirac operators in symplectic spin geometry and symplectic topology, which have b

  8/25/2026

• Science

  Spherical wave transformation

  Spherical wave transformations leave the form of spherical waves as well as the laws of optics and electrodynamics invariant in all inertial frames. They were defined between 1908 and 1909 by Harry Bateman and Ebenezer Cunningham, with Bateman giving the transformation its name. They correspond to the conformal group of "transformations by reciprocal radii" in relation to the framework of Lie sphe

  8/25/2026

• Science

  Sphuṭacandrāpti

  Sphuṭacandrāpti (Computation of True Moon) is a treatise in Sanskrit composed by the fourteenth-century CE Kerala astronomer-mathematician Sangamagrama Madhava. The treatise enunciates a method for the computation of the position of the moon at intervals of 40 minutes each throughout the day. This is one of only two works of Madhava that have survived to modern times, the other one being Veṇvāroha

  8/25/2026

• Science

  Spill kit

  Spill kits are typically single-use kits containing chemicals used for absorption of (hazardous) wastes. Ready-for-use kits typically contain personal protective equipment, decontamination or neutralizing agents, disposal containers, and signage markers. Sometimes, spill containment material will also be included.

  8/25/2026

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  Science

  Speeter–Anthony route

  The Speeter–Anthony route, also known as the Speeter–Anthony tryptamine synthesis (STS), is a well-known and widely used chemical synthesis route used in the synthesis of tryptamines, including psychedelic tryptamines like psilocin and 5-MeO-DiPT. It starts with indole or a ring-substituted indole. The scheme of the route is as follows: The route was first described by Merrill E. Speeter and Will

  8/25/2026

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  Science

  Somnium (novel)

  Somnium (Latin for "The Dream") — full title: Somnium, seu opus posthumum De astronomia lunari — is a novel written in Latin by Johannes Kepler in 1608/1609. It was first published in 1634 by Kepler's son, Ludwig Kepler, several years after the death of his father. In the narrative, an Icelandic boy and his witch mother learn of an island named Levania (the Hebrew word for the moon) from a daemon.

  8/25/2026

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  Science

  Sonoluminescence

  Sonoluminescence is luminescence induced by sound waves, such as in the emission of light from imploding bubbles in a liquid when excited by sound. Sonoluminescence is sometimes considered a kind of mechanoluminescence. However, mechanoluminescence is typically defined as pertaining to solids, while sonoluminescence usually pertains to liquids. The related terms acoustoluminescence and sonotribolu

  8/25/2026

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  Science

  Southern California Earthquake Center

  The Statewide California Earthquake Center (SCEC) is a collaboration of more than 1,000 scientists across 100 research institutions focused primarily on conducting research on earthquakes in Southern California and elsewhere by gathering data, conducting theoretical studies, and performing computer simulations; integrate information into a comprehensive, physics-based understanding of earthquake p

  8/25/2026

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  Science

  Songline

  A songline, also called dreaming track, is one of the paths across the land (or sometimes the sky) within the animist belief systems of the Aboriginal cultures of Australia which mark the route followed by localised "creator-beings" in the Dreaming. The paths of the songlines are recorded in traditional song cycles, stories, dance, and art, and are often the basis of ceremonies.

  8/25/2026

• Science

  Somos' quadratic recurrence constant

  In mathematical analysis and number theory, Somos' quadratic recurrence constant or simply Somos' constant is a constant defined as an expression of infinitely many nested square roots. It arises when studying the asymptotic behaviour of a certain sequence and also in connection to the binary representations of real numbers between zero and one. The constant named after Michael Somos. It is define

  8/25/2026

• Science

  Sonochemistry

  In chemistry, the study of sonochemistry is concerned with understanding the effect of ultrasound in forming acoustic cavitation in liquids, resulting in the initiation or enhancement of the chemical activity in the solution. Therefore, the chemical effects of ultrasound do not come from a direct interaction of the ultrasonic sound wave with the molecules in the solution.

  8/25/2026

• Science

  Source function

  The source function is a characteristic of a stellar atmosphere, and in the case of no scattering of photons, describes the ratio of the emission coefficient to the absorption coefficient. It is a measure of how photons in a light beam are removed and replaced by new photons by the material it passes through. Its units in the cgs-system are erg s−1 cm−2 sr−1 Hz−1 and in SI are W m−2 sr−1 Hz−1 . Th

  8/25/2026

• Science

  Sommerfeld–Kossel displacement law

  The Sommerfeld–Kossel displacement law states that the first spark (singly ionized) spectrum of an element is similar in all details to the arc (neutral) spectrum of the element preceding it in the periodic table. Likewise, the second (doubly ionized) spark spectrum of an element is similar in all details to the first (singly ionized) spark spectrum of the element preceding it, or to the arc (neu

  8/25/2026

• Science

  Sophomore's dream

  In mathematics, the sophomore's dream is the pair of identities (especially the first) ∫ 0 1 x

  8/25/2026

• Science

  Sound (nautical)

  In nautical terms, the word sound is used to describe the process of determining the depth of water in a tank or under a ship. Tanks are sounded to determine if they are full (for cargo tanks) or empty (to determine if a ship has been holed) and for other reasons. Soundings may also be taken of the water around a ship if it is in shallow water to aid in navigation.

  8/25/2026

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  Science

  Somerset Space Walk

  The Somerset Space Walk is a sculpture trail model of the Solar System, located in Somerset, England. The model uses the towpath of the 22-kilometre (14-mile) Bridgwater and Taunton Canal to display a model of the Sun and its planets in their proportionally correct sizes and distances apart. Unusually for a Solar System model, there are two sets of planets, so that the diameter of the orbits is re

  8/25/2026

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  Science

  Soundscape ecology

  Soundscape ecology is the study of the acoustic relationships between living organisms, human and other, and their environment, whether the organisms are marine or terrestrial. First appearing in the Handbook for Acoustic Ecology edited by Barry Truax, in 1978, the term has occasionally been used, sometimes interchangeably, with the term acoustic ecology. Soundscape ecologists also study the relat

  8/25/2026

• Science

  Sophrology

  Sophrology is a dynamic relaxation method developed by neuropsychiatrist Alfonso Caycedo from 1960 to 2001 and includes physical and mental exercises to promote health and well-being. (pp. 35–42). Emerging scientific studies suggest its potential benefits in various contexts, including stress reduction, anxiety management, and improved quality of life. (pp. 17–18, 45–46, 57, 60–61) The influences

  8/25/2026

• Science

  Null Island

  Null Island is the location at zero degrees latitude and zero degrees longitude (0°N 0°E), where the prime meridian and the equator intersect in the Atlantic Ocean near the Gulf of Guinea. Since there is no landmass located at these coordinates, it is not an actual island. The name is often used in mapping software as a placeholder to help find and correct database entries that have erroneously be

  8/25/2026

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  Science

  Solventogenesis

  Solventogenesis is the biochemical production of solvents (usually acetone and butanol) by Clostridium species. It is the second phase of ABE fermentation.

  8/25/2026

• Science

  Sonochemical synthesis

  Sonochemical synthesis is the process which utilizes the principles of sonochemistry to make molecules undergo a chemical reaction with the application of powerful ultrasound radiation (20 kHz–10 MHz). Sonochemistry generates hot spots that can achieve very high temperatures (5000–25.000 K), pressures of more than 1000 atmospheres, and rates of heating and cooling that can exceed 10^11 K/s. High i

  8/25/2026

• Science

  Sommerfeld effect

  In mechanics, Sommerfeld effect is a phenomenon arising from feedback in the energy exchange between vibrating systems: for example, when for the rocking table, under given conditions, energy transmitted to the motor resulted not in higher revolutions but in stronger vibrations of the table. It is named after Arnold Sommerfeld. In 1902, A. Sommerfeld analyzed the vibrations caused by a motor drivi

  8/25/2026

• Science

  Somatic mutation

  A somatic mutation is a change in the DNA sequence of a somatic cell of a multicellular organism with dedicated reproductive cells; that is, any mutation that occurs in a cell other than a gamete, germ cell, or gametocyte. Unlike germline mutations, which can be passed on to the descendants of an organism, somatic mutations are not usually transmitted to descendants. This distinction is blurred i

  8/25/2026

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  Science

  Southern Caribbean upwelling system

  The Southern Caribbean Upwelling system (SCUS) is a low latitude tropical upwelling system, where due to multiple environmental and bathymetric conditions water from the deep sea is forced to the surface layers of the ocean. The SCUS is located at about 10°N on the southern coast of the Caribbean sea basin off Colombia, Venezuela, and Trinidad. There are two main upwelling zones in the system t

  8/25/2026

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  Science

  Southern Ocean Observing System

  Southern Ocean Observing System (SOOS) is an international initiative of the Scientific Committee on Antarctic Research (SCAR) and the Scientific Committee on Oceanic Research (SCOR). It was officially launched in 2011. Its International Project Office is hosted by the Institute for Marine and Antarctic Studies (IMAS), University of Tasmania, Australia. The Southern Ocean, encircling Antarctica,

  8/25/2026

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  Science

  Spacetime

  In physics, spacetime, or the space-time continuum, is a mathematical model that fuses the three dimensions of space and the one dimension of time into a single four-dimensional continuum. Spacetime diagrams are useful in visualizing and understanding relativistic effects, such as how different observers perceive where and when events occur. Until the turn of the 20th century, the assumption had b

  8/25/2026

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  Science

  Southern blot

  Southern blot is a method used for detection and quantification of a specific DNA sequence in DNA samples. This method is used in molecular biology. Briefly, purified DNA from a biological sample (such as blood or tissue) is digested with restriction enzymes, and the resulting DNA fragments are separated by electrophoresis using an electric current to move them through a sieve-like gel or matrix,

  8/25/2026

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  Science

  Spatial scale

  Spatial scale is a specific application of the term scale for describing or categorizing (e.g. into orders of magnitude) the size of a space (hence spatial), or the extent of it at which a phenomenon or process occurs. For instance, in physics an object or phenomenon can be called microscopic if too small to be visible. In climatology, a micro-climate is a climate which might occur in a mountain,

  8/25/2026

• Science

  Spatial resolution

  In physics and geosciences, the term spatial resolution refers to distance between independent measurements, or the physical dimension that represents a pixel of the image. While in some instruments, like cameras and telescopes, spatial resolution is directly connected to angular resolution, other instruments, like synthetic aperture radar or a network of weather stations, produce data whose spat

  8/25/2026

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  Science

  Spallation

  Spallation is a process in which fragments of material (spall) are ejected from a body due to impact or stress. In the context of impact mechanics it describes ejection of material from a target during impact by a projectile. In planetary physics, spallation describes meteoritic impacts on a planetary surface and the effects of stellar winds and cosmic rays on planetary atmospheres and surfaces. I

  8/25/2026

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  Special functions

  Special functions are particular mathematical functions that have more or less established names and notations due to their importance in mathematical analysis, functional analysis, geometry, physics, or other applications. The term is defined by consensus, and thus lacks a general formal definition, but the list of mathematical functions contains functions that are commonly accepted as special.

  8/25/2026

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  Science

  Paracelsianism

  Paracelsianism (also Paracelsism; German: Paracelsismus) was an early modern medical movement based on the theories and therapies of Paracelsus. It developed in the second half of the 16th century, during the decades following Paracelsus's death in 1541, and it flourished during the first half of the 17th century, representing one of the most comprehensive alternatives to learned medicine, the tr

  8/25/2026

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  Science

  Space command

  A space command is a military organization with responsibility for space operations and warfare. A space command is typically a joint organization or organized within a larger military branch and is distinct from a fully independent space force. The world's first space command, the United States' Air Force Space Command was established in 1982 and later became the United States Space Force in 2019

  8/25/2026

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  Science

  Space-based solar power

  Space-based solar power (SBSP or SSP) is the concept of collecting solar power in outer space with solar power satellites (SPS) and distributing it to Earth. Its advantages include a higher collection of energy due to the lack of reflection and absorption by the atmosphere, the possibility of very little night, and a better ability to orient to face the Sun. Space-based solar power systems convert

  8/25/2026

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  Science

  Spatial multiplexing

  Spatial multiplexing or space-division multiplexing (SM, SDM or SMX) is a multiplexing technique in MIMO wireless communication, fiber-optic communication and other communications technologies used to transmit independent channels separated in space.

  8/25/2026