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FORM (symbolic manipulation system)
FORM is an open-source symbolic manipulation system created by Jos Vermaseren of NIKHEF, started in 1984 and released as open source in 2010, used for large quantum field theory calculations.
Formal charge
Formal charge is the hypothetical charge assigned to an atom in a Lewis structure, calculated as if bonding electrons were shared equally regardless of electronegativity.
Formal grammar
A formal grammar (grammar formalism) is a finite set of rewriting rules that generates the strings of a formal language, classifying syntax in the Chomsky hierarchy.
Formal language
A formal language is a possibly infinite set of finite strings over an alphabet, defined purely by form rather than meaning, usually specified by a formal grammar such as a context-free grammar.
Formal power series
A formal power series is an infinite sum whose coefficients lie in a fixed ring, treated as an algebraic object without asking whether it converges.
Formal scheme
A formal scheme is an algebraic geometry object built from the formal spectrum Spf(A) of a complete adic ring, retaining infinitesimal information to all orders.
Formal science
A formal science is a discipline, such as mathematics, logic, and theoretical computer science, that establishes its claims by proof within defined symbolic systems rather than by experiment.
Formal synthesis
A formal synthesis is a chemical synthesis ending at a known intermediate previously converted into the desired target, whose published final steps complete the route.
Formal system
A formal system, or formal logical system, is a set of axioms and inference rules for generating theorems, with proofs checkable mechanically; it underlies Gödel's incompleteness theorems.
Formaldehyde
Formaldehyde, also known as methanal, is the simplest aldehyde, a colorless, flammable gas with a pungent odor used mainly to make resins for wood, paper, and textiles.
Formamide
Formamide, also known as methanamide or carbamaldehyde, is the simplest amide, a colorless liquid used as a solvent and chemical intermediate, and a molecule detected in interstellar space.
Formant
A formant is a broad peak in the spectral envelope of a sound caused by resonance; in speech, the vocal tract's formants distinguish one vowel from another.
Formate pathway in CO2 hydrogenation
The formate pathway in CO2 hydrogenation is a reaction mechanism in which CO2 is hydrogenated via a formate intermediate to methanol, avoiding the CO route, on Cu/ZnO catalysts.
Formation and evolution of globular clusters
The formation and evolution of globular clusters covers how dense systems of roughly 100,000 old stars formed, peaked at redshift 2.5, and dissolved into galactic halos.
Formation and evolution of the Solar System
The Solar System formed about 4.6 billion years ago from the collapse of a giant molecular cloud, with planets accreting from a disk around the young Sun.
Formation constant
The formation constant, or stability constant, is the equilibrium constant for a metal ion binding one or more ligands to form a coordination complex in solution.
Formative assessment
Formative assessment, also called assessment for learning, is a planned, ongoing process in which teachers and students use evidence of learning to adjust instruction, unlike summative assessment.
Formazan
A formazan is a highly colored nitrogen-rich organic compound, known since the late 1800s, used as a dye and formed in tetrazolium assays of cell viability such as the MTT assay.
Former constellations
Former constellations, also called obsolete constellations, are star patterns that appeared on historical star charts but are not among the 88 constellations the IAU recognized in 1922.
Formic acid
Formic acid, also known as methanoic acid (HCOOH), is the simplest carboxylic acid, a corrosive liquid found in ant venom and used industrially for silage preservation and leather tanning.
Formica (plastic)
Formica is a brand of high-pressure decorative laminate, invented in 1913 in Cincinnati as an electrical insulator and later a defining material of mid-century American kitchens.
Formoterol
Formoterol is a long-acting inhaled beta2-adrenergic agonist (LABA) used as a bronchodilator in the maintenance treatment of asthma and COPD, acting within minutes and lasting at least 12 hours.
Formula
A formula is an expression in mathematical symbols stating a fact, rule, or relationship among quantities; in logic it is a well-formed expression denoting a truth value.
Formula for primes
A formula for primes is an expression that generates prime numbers, such as Mills' 1947 constant formula, Willans' 1964 nth-prime formula, and a 26-variable polynomial.
Formula unit
A formula unit is the smallest electrically neutral grouping of ions that a chemical formula represents, the counting unit for ionic compounds that do not exist as discrete molecules, like NaCl.
Fornax
Fornax, originally called Fornax Chemica, is a faint southern constellation created by Nicolas-Louis de Lacaille in the 18th century, best known for the nearby Fornax cluster of galaxies.
Fornax Dwarf
The Fornax Dwarf, also called the Fornax dwarf spheroidal galaxy, is a faint satellite of the Milky Way in the constellation Fornax, discovered by Harlow Shapley in 1938.
Forschungszentrum Jülich
Forschungszentrum Jülich, founded in the 1950s as a nuclear research facility, is one of Europe's largest interdisciplinary research centers, with priorities in information, energy, and bioeconomy.
Forsterite
Forsterite is a magnesium silicate mineral, Mg2SiO4, forming the magnesium-rich end of olivine, the most abundant mineral in the Earth's upper mantle; its gem variety is peridot.
Fort Union Formation
The Fort Union Formation is a coal-bearing Paleocene rock unit underlying parts of Wyoming, Montana, North Dakota, and South Dakota, named in 1862 near Buford, North Dakota.