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Londa Schiebinger
Londa Schiebinger, born in 1952, is an American historian of science and Stanford professor who studies how gender shapes science and leads the Gendered Innovations project.
London Clay
London Clay, or London Clay Formation, is an Early Eocene marine clay formation underlying much of southern England, known for its fossils and as the tunnelling medium beneath London.
London dispersion force
The London dispersion force is the weakest intermolecular force, a universal attraction from temporary dipoles that grows stronger in larger, more polarizable atoms and molecules.
London penetration depth
The London penetration depth is the distance over which a magnetic field decays as it enters a superconductor, set by the superconducting electron density and typically tens of nanometers.
Lone pair
A lone pair, or unshared pair, is a pair of valence electrons on a single atom that does not take part in a covalent bond.
Lonely runner conjecture
The Lonely Runner Conjecture, or lonely runner problem, is an unsolved number theory problem posed by Jörg M. Wills in 1967 concerning runners on a unit circle.](20 words)
Long and short scales
The long and short scales are two competing systems for naming large numbers: in the short scale each new term is 1,000 times the previous one, in the long scale 1,000,000 times.
Long division
Long division is a standard method for dividing multi-digit numbers by hand, breaking the problem into a series of steps and allowing arbitrarily large numbers to be computed on paper.
Long Ju
Long Ju is an experimental condensed-matter physicist at MIT who studies electron correlations in atomically thin materials, known for the first fractional quantum anomalous Hall effect in graphene.
Long profile
A long profile of a river is a plot of channel elevation against distance downstream, a diagnostic of tectonic uplift, rock resistance, and base level changes.
Long tail
The long tail, or long-tailed distribution, is a probability distribution whose right tail decays so slowly that shifting the threshold barely changes the tail probability.
Long ton
The long ton, also called the imperial ton, is a British unit of mass equal to 2,240 pounds, about 1,016 kilograms, traditionally used in shipping.
Long Wavelength Array
The Long Wavelength Array (LWA) is a radio telescope in New Mexico and California observing at 10 to 88 MHz, the lowest frequencies observable from the ground.
Long-baseline interferometry
Long-baseline interferometry is an observational astronomy technique that combines signals from telescopes separated by long distances, resolving fine detail in celestial sources at radio, optical, and infrared wavelengths.
Long-Baseline Neutrino Facility
The Long-Baseline Neutrino Facility (LBNF) is a US facility under construction to send a Fermilab neutrino beam about 1,300 km to the DUNE detector in South Dakota.
Long-chain alkylphenols
Long-chain alkylphenols are man-made, estrogen-like phenols bearing long alkyl chains, chiefly octylphenol and nonylphenol, which make up over 95 percent of the alkylphenol market and are used mainly as surfactant intermediates.
Long-lived particles
Long-lived particles (LLPs) are particles that are stable or live long enough for their decays to be experimentally distinguishable in time or position from where they were produced.
Long-period radio pulsars
Long-period radio pulsars are compact stars, neutron stars or white dwarfs, that emit radio pulses every tens of seconds to hours, beyond the classical pulsar range.
Long-period radio transient
A long-period radio transient is a Galactic source of repeating, strongly polarized radio bursts on periods of minutes to hours, identified in 2022 with about a dozen members known.
Long-period variable
A long-period variable is a pulsating red giant or supergiant star, mostly on the asymptotic giant branch, whose brightness changes over periods of tens to more than a thousand days.
Long-slit spectroscopy
Long-slit spectroscopy is an astronomical observing technique that disperses light from a narrow strip of sky, recording a separate spectrum for each point along the slit.
Long-term nuclear waste warning messages
Long-term nuclear waste warning messages are communication attempts to deter human intrusion at nuclear waste repositories for 10,000 years, when languages may no longer be understood.
Long-wave infrared
Long-wave infrared (LWIR) is the infrared band from 8 to 15 micrometers, also called the thermal infrared, where room-temperature objects emit most of their radiation.
Longest path problem
The longest path problem is the NP-hard problem of finding a maximum-length simple path in a graph, solvable in linear time on directed acyclic graphs and applied to project scheduling.
Longitude
Longitude is the geographic coordinate measuring distance east or west of the prime meridian at Greenwich, expressed in degrees and counted up to 180 in each direction.
Longitude Act
The Longitude Act was a British Act of Parliament passed in 1714 that offered prizes of up to £20,000 for a practical method of determining longitude at sea.
Longitude of the ascending node
The longitude of the ascending node (Ω) is the angle in a reference plane from a reference direction to an orbit's ascending node, one of six orbital elements.
Longitudinal connectivity
Longitudinal connectivity is the upstream–downstream dimension of river connectivity, allowing water, sediment, nutrients, and organisms to move freely along the channel; dams are its leading cause of loss.
Longitudinal data analysis
Longitudinal data analysis is the collection of statistical methods for data measured repeatedly on the same subjects over time, separating within-subject change from between-subject differences.
Longitudinal mediation analysis
Longitudinal mediation analysis is a family of statistical methods for estimating direct and indirect effects when the mediator, the outcome, or both are measured repeatedly over time.