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Fritz Strassmann
Fritz Strassmann (1902–1980) was a German chemist who, with Otto Hahn, identified barium in neutron-irradiated uranium in December 1938, the decisive step in the discovery of nuclear fission.
Fritz Ursell
Fritz Ursell (1923–2012) was a British applied mathematician who first proved the existence of trapped modes in water waves, analyzed the Kelvin ship-wave pattern, and introduced the Ursell number.
Fritz Vögtle
Fritz Vögtle (1939–2017) was a German organic chemist, professor and director of the Kekulé Institute at Bonn, whose 1978 cascade molecules opened dendrimer chemistry and whose group templated catenanes, rotaxanes, and knots.
Fritz Weigert
Fritz Weigert (1876–1947) was a German-British photochemist, professor of photochemistry at Leipzig from 1914 until his 1935 dismissal, known for the Weigert effect of photo-induced anisotropy.
Fritz Zwicky
Fritz Zwicky (1898–1974) was a Swiss astronomer at Caltech who inferred dark matter in the Coma cluster in 1933 and co-predicted neutron stars with Walter Baade.
Frobenius algebra
A Frobenius algebra is a finite-dimensional algebra over a field carrying a nondegenerate bilinear form compatible with multiplication, with examples including group algebras and matrix rings.
Frobenius coin problem
The Frobenius coin problem, also called the coin problem or money-changing problem, asks for the largest integer not expressible as a nonnegative combination of given coprime integers.
Frobenius group
A Frobenius group is a transitive permutation group in which no non-identity element fixes more than one point, studied by Georg Frobenius in 1900 and 1901 using his new theory of group characters.
Frobenius method
The Frobenius method, reported by Georg Frobenius in 1873, solves linear ordinary differential equations by power series and produces classical special functions such as Bessel and Legendre functions.
Frobenius norm
The Frobenius norm, also called the Hilbert-Schmidt norm, is a matrix norm defined as the square root of the sum of squared absolute entries, named for Ferdinand Georg Frobenius.
Frobenius reciprocity
Frobenius reciprocity is a theorem of representation theory stating that induction and restriction between a group and a subgroup are adjoint, introduced by Frobenius in 1898.
Frobenius theorem (real division algebras)
The Frobenius theorem is a result in abstract algebra stating that the only finite-dimensional associative division algebras over the real numbers are R, C, and the quaternions, proved by Ferdinand Georg Frobenius in 1877.
From the Earth to the Moon
From the Earth to the Moon (De la Terre à la Lune) is an 1865 Jules Verne novel in which the Baltimore Gun Club fires a three-man projectile at the Moon from Florida.
Frontal polymerization
Frontal polymerization is a polymerization method in which a localized, self-sustaining reaction front propagates through monomer, converting it to polymer within seconds and curing composites far faster than ovens.
Frontier analysis
Frontier analysis is a family of statistical and econometric methods that estimate a best-practice production frontier from data and measure how far each firm falls short of it.
Frontier Formation
The Frontier Formation is a Cretaceous sandstone and shale rock unit widespread in Wyoming and adjacent states, named in 1901 near the coal town of Frontier, Wyoming.
Frontiers in Physics (book series)
Frontiers in Physics is a physics monograph and lecture-note book series founded by David Pines in 1961, whose inaugural titles included two books by Richard Feynman; it is currently published by CRC Press.
Frontogenesis
Frontogenesis is the formation or intensification of a weather front through tightening of the horizontal potential temperature gradient, a process quantified by Petterssen in 1936.
Frost
Frost, also called ground frost, is a deposit of ice crystals on surfaces such as grass and windows cooled below 0 °C, typically on clear, calm nights, with types including hoar frost and rime.
Frost heave
Frost heave is the upward displacement of the ground surface caused by ice lenses forming in freezing soil, damaging roads, railways, pipelines, and building foundations in cold regions.
Frost point
The frost point is the temperature to which air must be cooled at constant pressure for water vapor to deposit as frost instead of condensing as dew.
Frost weathering
Frost weathering, also called frost shattering or freeze-thaw weathering, is the breakdown of rock by freezing water in cracks and pores, a key process in cold, non-glacial climates and mountains.
Froth flotation
Froth flotation is a mineral separation process in which hydrophobic particles attach to air bubbles and rise as a froth, the dominant method of mineral beneficiation.
Froude number
The Froude number (Reech number) is a dimensionless quantity in fluid mechanics, the ratio of inertial to gravitational forces, used in open-channel hydraulics and ship model testing.
FRS Ion Catcher
The FRS Ion Catcher is a facility at the GSI Helmholtz Centre in Darmstadt, Germany, that slows exotic nuclei in a gas-filled stopping cell for precision mass measurements.
Frustrated Lewis pair
A frustrated Lewis pair (FLP) is a Lewis acid and base prevented from forming an adduct, leaving both reactive; pairs famously cleave hydrogen without metals.
Frustrated Lewis pair chemistry in metal–organic frameworks
Frustrated Lewis pair chemistry in metal–organic frameworks embeds sterically prevented Lewis acid–base pairs in MOF pores, proposed computationally around 2015 and later realized as recyclable catalysts for hydrogenation and CO2 conversion.
Frustrated Lewis pair CO2 activation
Frustrated Lewis pair CO2 activation is the capture and distortion of carbon dioxide by a sterically hindered Lewis acid and base that cannot form a classical adduct.
Frustrated magnetism
Frustrated magnetism is the study of magnets whose competing spin interactions cannot all be satisfied at once, preventing simple magnetic order and producing spin liquids.
Frustum
A frustum (plural frusta, frustums) is the portion of a solid lying between two parallel planes, most commonly a cone or pyramid cut by a plane parallel to its base.