Technology Glossary

Laser Power Beaming

A wireless power-transfer method that converts electricity into a directed laser beam, sends it across a line of sight, and converts the received light back into electricity. Practical systems must manage conversion losses, beam tracking, atmospheric interference and laser safety.

Laser Wakefield Acceleration

Laser wakefield acceleration uses an intense laser pulse to drive a wave through plasma. The wave creates extremely strong electric fields that can accelerate electrons to gigaelectronvolt energies over centimetres, offering a more compact route to high-energy electron beams than conventional radio-frequency accelerators.

Laser-Induced Breakdown Spectroscopy(LIBS)

A technique that fires a laser pulse at a target to create a tiny plasma, then analyses the emitted light to identify chemical elements. Rover instruments can use LIBS from several metres away to compare many rock targets without drilling each one.

Late-Stage Functionalization

Adding or changing a functional group near the end of a molecule's synthesis to rapidly create related variants.

Lateral Movement

The technique of moving from one compromised system to other connected systems after initial access.

Launch Window

A limited period when a rocket can launch and still follow the required trajectory to its destination. The window depends on orbital geometry, vehicle readiness, weather, range safety and mission constraints.

Layered Aviation Security

A design approach that uses several independent preventive, detection and response controls so that failure of one measure does not determine the outcome. In aviation, layers can span personnel screening, restricted access, cockpit procedures, crew coordination, transponder alerts, air-traffic control and airport emergency response.

LDL Cholesterol(LDL-C)

The amount of cholesterol carried in the blood by low-density lipoprotein particles. Persistently elevated LDL cholesterol contributes to plaque buildup in arteries and is a major modifiable risk factor for cardiovascular disease.

Leadless Pacemaker

A compact pacemaker implanted directly inside a heart chamber through a catheter, without the transvenous leads and chest pocket used by conventional systems.

Leap Second

A leap second is an occasional one-second adjustment to UTC used to keep civil atomic time close to Earth's irregular rotation. GPS Time does not include leap seconds, so GPS receivers use broadcast offset information when converting to UTC.

Lenticular Lens

A narrow cylindrical lens, usually used in an array, that directs different parts of an underlying image toward different viewing angles. Lenticular lenses can make a surface show different pictures or an illusion of motion without an electronic display.

Light Dark Matter

Hypothetical dark matter particles with masses below the range targeted by many traditional direct-detection experiments.

Light-Gated Ion Channel

A membrane protein that opens or closes in response to light, allowing specific ions to cross the cell membrane.

Lignocellulosic Biomass

Plant-derived material composed mainly of cellulose, hemicellulose, and lignin, including wood, straw, grasses, and agricultural residues. It is abundant and does not have to be edible, but its resistant structure makes conversion into fuels and chemicals technically difficult.

Limit of Detection(LOD)

The lowest amount or concentration of a substance that an analytical method can distinguish reliably from background noise under specified conditions. It indicates detectability, not necessarily the level that can be measured with acceptable accuracy and precision.

Link Budget

An accounting of transmitter power, antenna gains, distance losses and receiver sensitivity used to determine whether a radio signal can be detected reliably.

Lithium-Mediated Nitrogen Reduction(Li-NRR)

An electrochemical route in which lithium species help activate nitrogen gas so it can be protonated into ammonia. The method can achieve useful selectivity and rates, but conventional lithium deposition demands a strongly negative potential.

Little Red Dot

A compact, red source seen by the James Webb Space Telescope in the early universe. Little red dots often show broad hydrogen lines, but their mixture of stars, gas and actively feeding black holes remains under study.

Lobate Scarp

A long, curved cliff produced when one block of planetary crust is pushed over another along a thrust fault. Lobate scarps on Mercury are key surface evidence that the planet contracted as its interior cooled.

Local AI Model

An AI model that runs on a user's own device or private infrastructure rather than relying entirely on a remote cloud service.

Local Large Language Model

A large language model whose files and inference software run on a user-controlled computer or private server, allowing prompts and documents to be processed without relying on a hosted cloud model for each request.

Location Privacy

Location privacy concerns how information about a person's or device's physical whereabouts is collected, inferred, stored and shared. Smartphones and connected services can derive location from GNSS as well as cellular, Wi-Fi and other signals.

Location-Based Services(LBS)

Location-Based Services (LBS) are software services that use a device's geographic position to provide relevant functions or information, such as maps, ride-hailing, nearby search, delivery tracking and geofencing.

Long-Range Inhibitory Interneuron

An inhibitory neuron whose axon influences targets far beyond its local circuit. Unlike most cortical interneurons, it can coordinate activity across separated brain regions by reducing or timing neuronal firing.

Longitudinal Clustering

An unsupervised method that groups people or observations according to similarities in how measurements change across multiple time points.

Longitudinal Study

A research design that follows the same people, households or other units over multiple points in time. Comparing repeated observations helps researchers identify how behaviour or outcomes change, although it does not by itself prove what caused the change.

Look-Elsewhere Effect

The increased chance of finding an apparently significant fluctuation when many datasets, models, energy ranges or locations are tested. Statistical significance is adjusted to account for the number of opportunities available for a chance result to appear.

Technology glossary