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Electricity, magnetism and electronics · fields, quantum physics and useful devices

A researched history of electricity, magnetism and electronics, tracing experimental observations into quantitative laws, electromagnetic field theory, electrical systems and microscopic device physics. Gregorian BCE/CE calendar; research cutoff: 3 November 2026. Quantum mechanics is included where it explains how materials and devices work—and why some improvements eventually encounter limits. This is a substantial comparative survey rather than a claim to include every scientist, regional tradition or electrical product.

Explore the strands

Use Separate by tags to compare electrostatics, charge, current, magnetism, induction, field theory, measurement, circuits, power, communication, vacuum tubes, quantum mechanics, semiconductors, transistors, manufacturing, integrated circuits, photonics, superconductivity, tunnelling, spintronics, sensors, medical electronics, electrochemistry and power electronics. An event can belong to several strands because these histories develop together.

The full view includes ancient historical attributions. Useful zoom windows are 1600–1900 for experimental electromagnetism and power, 1890–1975 for electrons, quantum theory and semiconductor development, and 1940–2027 for modern devices and manufacturing. Expand moments for their evidence, image qualifications, relationships and attached explanatory cards. Sixteen bounded duration bands provide editorial reading guides; their endpoints do not claim to date the complete birth and death of a scientific field.

From observation to quantitative theory

The earliest Thales marker is a conventional, approximate historical attribution, not a dated surviving notebook or proof of the first human encounter with electricity. Chinese magnetic-needle traditions, Peregrinus’s dated letter and Gilbert’s experimental magnetism demonstrate different forms of evidence. A compass is a working magnetic instrument before anyone has a quantum theory of iron.

Static generators, charge-storage jars, conduction experiments, charge terminology and Coulomb’s measurements make electricity experimentally tractable. Volta’s pile supplies sustained current. Ørsted, Ampère, Biot and Savart connect current with magnetism; Faraday and Henry investigate induction. Ohm, Kirchhoff, bridge measurements and equivalent-network theory help make circuits calculable. Quantitative units and instruments develop alongside the laws.

Faraday’s magneto-optic effect connects light and magnetism experimentally. Maxwell’s 1861–1862 development, 1864 presentation/1865 paper and 1873 Treatise are distinct milestones. The compact modern set of four equations in vector notation is a later mathematical presentation, so its explanatory image is not labeled as a facsimile of the 1865 paper. Hertz’s wave experiments test electromagnetic theory before radio becomes a reliable communication service.

Power, communication and active electronics

Motors and generators convert energy in opposite directions. Transformers and distribution systems connect laboratory induction with industrial electricity. Swan, Edison, Stanley, Tesla, Ferraris and many other contributors belong to overlapping technical and commercial histories; the timeline avoids assigning one universal invention of electricity to a single company or date. Early urban stations, Niagara and cables illustrate systems requiring generation, insulation, control, measurement and infrastructure.

Thermionic valves, grid control and feedback introduce controllable electron flow and gain. Electron-beam instruments make signals visible. Semiconductor rectifiers and vacuum tubes coexist before transistors become reliable products. Radio, telephone and computing applications create demanding engineering problems, but demand alone does not supply the necessary material purity, interfaces or fabrication processes.

Why quantum mechanics matters to later improvements

Quantum theory supplies more than a final chapter about quantum computers. Quantized transitions explain emission and absorption; matter waves and state occupancy support crystal-state and band descriptions. Band gaps, carrier populations and impurity control help explain why a metal, an insulator and a semiconductor behave differently. Junctions and transistor action require this microscopic understanding alongside classical electrostatics and circuit models.

The timeline separates Planck’s quantum hypothesis, Einstein’s light quanta, Bohr’s atomic levels, de Broglie’s matter waves, Pauli’s exclusion principle, Heisenberg’s matrix mechanics, Schrödinger’s wave equation, Fermi–Dirac statistics, Dirac’s relativistic electron theory, quantum exchange and Bloch/Wilson solid-state work. These are dated research steps, not a claim that a modern semiconductor design manual appeared all at once.

Several practical paths make the connection concrete:

  • Quantum states and band engineering → junctions, transistors, heterostructures, LEDs and lasers. Suitable interfaces, purity, doping and growth are equally essential engineering steps.
  • Tunnelling → tunnel diodes, field emission, scanning tunnelling microscopy and superconducting junctions. Tunnelling also creates unwanted leakage through barriers meant to insulate, motivating gate-stack and geometry changes.
  • Spin and collective magnetism → resonance, magnetic sensors and spin-valve disk heads. A discovery in a low-temperature or special sample still needs additional engineering before commercial use.
  • Superconducting phase and quantum Hall effects → precision voltage/resistance references. Quantum physics becomes everyday measurement infrastructure, culminating in a revised SI based on fixed constants.
  • Nuclear spins + controlled fields + RF electronics + computation → MRI. Quantum response and classical engineering are combined within one useful instrument.

Classical electromagnetism remains extremely useful. Power systems, antennas and much circuit behaviour use classical field and network models, while quantum-derived device parameters describe the materials. The history is an accumulation and refinement of models suited to their scales, rather than every older theory becoming useless immediately.

Theory is necessary, while fabrication makes it practical

Lilienfeld’s field-effect concept long precedes a dependable MOS device. Bardeen’s surface-state reasoning and Brattain’s experiments produce point-contact amplification; Shockley’s junction concept then needs controlled crystal growth. Zone refining, diffusion, lithography, oxide masking, Hoerni’s planar process, Noyce’s interconnections and Atalla/Kahng’s interface work turn scientific possibilities into manufacturable devices.

Kilby’s integrated-circuit demonstration, Fairchild’s planar circuits, CMOS, analogue ICs, memory, microprocessors, CAD and SPICE solve different levels of the problem. Moore’s integration observation and Dennard-style constant-field scaling are related historical ideas with different assumptions. Neither guarantees unlimited automatic speed or energy improvement.

Later examples show responses to limits: high-k/metal gates manage leakage; fin and gate-all-around structures improve electrostatic control; EUV supports patterning; wide-bandgap materials expand power-device options. A marketed node number is not a literal universal gate length. TSMC’s reported fourth-quarter 2025 nanosheet production is separated from imec’s 2026 CFET research modules. IBM’s 2026 cryogenic-system connection is an engineering step; its future fault-tolerance targets remain future objectives.

The companion computer-architecture timeline covers how computing machines are organized. Mining through time covers extraction and material-supply pressures. This timeline concentrates on the physics, devices, measurements and electrical systems that connect those histories.

Evidence, priority and dates

Sources prioritize original papers, patents and theses; laboratory and standards-body records; museum artifact and engineering histories; creator lectures and retrospectives; and the Nobel Foundation’s scientific documentation. Institutional chronologies are useful guides, with abbreviated statements cross-checked where they blur separate stages. Manufacturer records establish reported processes and products, not independent proof of universal superiority.

A paper, theoretical proposal, working device, patent filing, public announcement, commercial product, volume-production report and later Nobel award can all have different dates. The event type states which one is being plotted. Point-contact amplification on 16 December 1947 precedes Bell Labs’ public announcement in June 1948. Working MOS devices in 1959 precede the 1960 demonstration. Early tunnelling experiments, their publication and later device promotion are not collapsed into one event. The 1985 macroscopic-circuit experiments are separate from their 2025 Nobel recognition.

Year-only dates plot on January 1; month-only dates on the first day. These are anchors rather than claims of exact days or midnight events. Broad and approximate periods have presumptive outlines. The Peregrinus date belongs to the manuscript’s closing, while an ancient attributed observation remains approximate. The transatlantic radio moment is explicitly a reported milestone rather than an unqualified assertion of a fully documented service.

Directional arrows mark specifically explained enabling connections or continuations. Other arcs are tagged reading paths or comparisons: occurring later or sharing a topic does not alone prove direct causal influence, sole priority or corporate descent. The explanatory cards are undated concepts attached to genuine dated milestones.

Images and backgrounds

Fifteen individually credited Commons images use public-domain, CC0 or Creative Commons licenses permitting reuse. Seventeen key moments have images; thirteen reading periods have thematic backgrounds, with an additional overall timeline backdrop. Later apparatus photographs and replicas retain explicit qualifications: the transistor is a replica; the modern transmon is not the 1985 experiment; the MRI scanner is not Lauterbur’s prototype; the wafer is not identified as TSMC N2; the RGB package is not the original 1993 blue LED. The later Tesla fan illustrates the motor tradition, and the modern Maxwell equation presentation is not an original-paper facsimile.

Backgrounds illustrate the strand rather than claiming one photograph depicts every date or device in the interval. Capture dates and historical milestone dates remain distinct. No changes beyond thumbnail scaling. Reuse rights in these images do not automatically extend to every linked publication.

Derived image: Chetvorno · Hertz drawing of his spark transmitter 1888.png · Public domain; rights.

Duration correction: Ongoing subjects previously drawn through a present/research cutoff are represented at their original starts, with no end asserted. Existing moments at those coordinates are reused; their attached cards retain the former duration’s notes, sources, tags and media. Bounded historical and coverage intervals remain durations.

178 moments · 0600-01-01T00:00:00Z BCE – 2026-08-19T00:00:00Z CE · by @athan · @athan

A durable transatlantic telegraph cable enters service

  • communication
  • circuits
  • applications

Cable operation exposes practical consequences of capacitance, resistance, signalling delay and testing. The successful 1866 system follows the short-lived 1858 cable and shows why a circuit’s distributed properties matter. **Milestone:** communication-system operation. **Historical date:** 1866. **Dating:** Proleptic Gregorian calendar, UTC. Year-only and month-only dates use the first day as plotting anchors, not claimed exact days or clock times; approximate periods have presumptive outlines. There is no historical year zero. **Sources:** - [Smithsonian Archives Center: Cyrus Field and the successful 1866 Atlantic cable](https://americanhistory.si.edu/explore/exhibitions/cyrus-field-and-transatlantic-telegraph-cable) - [Electromagnetism History: 1850-1869 - Magnet Academy](https://nationalmaglab.org/magnet-academy/history-of-electricity-magnetism/timeline/1850-1869/)

Date precision
year
Coordinate convention
Proleptic Gregorian calendar, UTC. Year-only and month-only dates use the first day as plotting anchors, not claimed exact days or clock times; approximate periods have presumptive outlines. There is no historical year zero.

Sources

Related

Open A durable transatlantic telegraph cable enters service in the timeline