Quantum chronicles
The story of the quantum world as one timeline: from the moment Max Planck introduced the quantum in 1900, through the theory that followed, the algorithms that turned it into a threat, the machines being built now, and the standards written to survive them. Each entry links to its wiki page where one exists, and to an outside reference.
The birth of quantum theory1900 to 1921
- 1900Physics
Planck introduces the quantum
To explain black-body radiation, Max Planck proposes that energy comes in discrete packets, E = h nu, defining Planck's constant and starting quantum theory.
Wikipedia - 1905Physics
Einstein explains the photoelectric effect
Albert Einstein treats light as quanta (later called photons), the work for which he received the 1921 Nobel Prize.
Wikipedia - 1913Physics
Bohr's model of the atom
Niels Bohr proposes that electrons occupy quantized orbits, explaining atomic spectra.
Wikipedia
The quantum revolution1922 to 1935
- 1922Physics
Stern-Gerlach experiment
Silver atoms split into two beams, demonstrating that angular momentum (spin) is quantized.
Wikipedia - 1924Physics
De Broglie's matter waves
Louis de Broglie proposes that particles have an associated wavelength, unifying wave and particle pictures.
Wikipedia - 1925Physics
Matrix mechanics
Werner Heisenberg formulates the first complete quantum mechanics; Pauli states the exclusion principle the same year.
Wikipedia - 1926Physics
Schrodinger's wave equation
Erwin Schrodinger gives the wave-function description of quantum systems; Max Born interprets its square as a probability.
Wikipedia - 1927Physics
Uncertainty principle and the Solvay Conference
Heisenberg publishes the uncertainty principle; the fifth Solvay Conference gathers the founders and stages the Bohr-Einstein debates.
Wikipedia - 1928Physics
The Dirac equation
Paul Dirac unifies quantum mechanics with special relativity and predicts antimatter.
Wikipedia - 1935Physics
EPR paradox and Schrodinger's cat
Einstein, Podolsky and Rosen question whether quantum mechanics is complete; Schrodinger names entanglement and poses his cat thought experiment.
Wikipedia
Fields and foundations1936 to 1975
- 1947-49Physics
Quantum electrodynamics
Feynman, Schwinger and Tomonaga build QED, the quantum field theory of light and matter, and share the 1965 Nobel Prize.
Wikipedia - 1957Physics
Everett's many-worlds interpretation
Hugh Everett proposes that all measurement outcomes occur in branching worlds, with no wavefunction collapse.
Wikipedia - 1964Physics
Bell's theorem
John Bell proves that no local hidden-variable theory can reproduce all of quantum mechanics, making entanglement experimentally testable.
Wikipedia - 1970Physics
Decoherence theory
Dieter Zeh explains how interaction with the environment makes quantum superpositions look classical, a key idea for building qubits.
Wikipedia
Cryptography and the quantum idea1976 to 1993
- 1976Cryptography
Diffie-Hellman key exchange
Whitfield Diffie and Martin Hellman invent public-key cryptography, the kind of scheme a future quantum computer would threaten.
Wikipedia - 1977
- 1981Computing
Feynman proposes quantum computing
Richard Feynman argues that simulating quantum physics needs a quantum machine, seeding the idea of the quantum computer.
Wikipedia - 1982Physics
Aspect's Bell tests and the no-cloning theorem
Alain Aspect's experiments back quantum mechanics over local hidden variables; the no-cloning theorem shows an unknown quantum state cannot be copied.
Wikipedia - 1984Cryptography
BB84 quantum key distribution
Charles Bennett and Gilles Brassard design the first quantum key distribution protocol, using physics rather than computational hardness.
Wikipedia - 1985Computing
Deutsch's quantum Turing machine
David Deutsch defines the universal quantum computer and the first algorithm showing a quantum advantage. Elliptic-curve cryptography is also proposed this year.
Wikipedia - 1993Computing
Quantum teleportation
Bennett and colleagues show how to transfer an unknown quantum state using entanglement and two classical bits.
Wikipedia
Quantum algorithms1994 to 2006
- 1994Computing
Shor's algorithm
Peter Shor shows a quantum computer could factor integers and break RSA and elliptic-curve cryptography in polynomial time, launching the field of post-quantum cryptography.
Wikipedia - 1996Computing
Grover's algorithm
Lov Grover finds a quantum search giving a quadratic speedup, which halves the effective strength of symmetric keys and hashes.
Wikipedia - 1998Computing
First working qubits
The first small nuclear-magnetic-resonance quantum computers run simple algorithms on two qubits.
Wikipedia - 2001Computing
Shor's algorithm demonstrated
An IBM team factors the number 15 with Shor's algorithm on a 7-qubit NMR machine, the first physical demonstration.
Wikipedia
The hardware race2007 to 2019
- 2007Computing
D-Wave demonstrates an annealer
D-Wave shows a 16-qubit quantum annealing prototype, beginning its commercial push.
Wikipedia - 2011Computing
First commercial quantum computer
D-Wave One goes on sale, the first commercially available quantum computer, using quantum annealing rather than the universal gate model.
Wikipedia - 2012Physics
Nobel Prize for measuring single quanta
Serge Haroche and David Wineland share the physics Nobel for methods to observe and control individual quantum systems.
Wikipedia - 2015Physics
Loophole-free Bell test
A Delft experiment closes the main loopholes in Bell tests, all but ruling out local hidden variables. The NSA also signals a coming move to quantum-resistant cryptography.
Wikipedia - 2016Computing
Cloud quantum computing and a quantum satellite
IBM opens a quantum processor to the public cloud, and China launches the Micius satellite for space-based quantum communication.
Wikipedia - 2016Cryptography
NIST opens post-quantum standardization
NIST announces a public competition to standardize quantum-resistant public-key algorithms.
Wikipedia - 2019Computing
Google's quantum supremacy claim
Google reports that its 53-qubit Sycamore chip performed a task beyond classical reach, a claim IBM contested. The first demonstration of its kind.
Wikipedia
Advantage, standards, and scale2020 to today
- 2020Computing
Photonic quantum advantage
China's Jiuzhang photonic machine reports a boson-sampling advantage, an independent route to beyond-classical computation.
Wikipedia - 2021Computing
127 qubits and new companies
IBM unveils the 127-qubit Eagle processor; IonQ becomes publicly traded and Quantinuum is formed from Honeywell and Cambridge Quantum.
Wikipedia - 2022Cryptography
NIST picks its first algorithms, and two finalists fall
NIST selects Kyber, Dilithium, Falcon and SPHINCS+ for standardization. The same year Rainbow and the isogeny scheme SIKE are broken by classical attacks.
Wikipedia - 2022Computing
Xanadu's photonic advantage
Xanadu's Borealis machine reports a programmable photonic quantum advantage, published in Nature.
Wikipedia - 2022Physics
Nobel Prize for entanglement
Alain Aspect, John Clauser and Anton Zeilinger share the physics Nobel for experiments with entangled photons and violations of Bell inequalities.
Wikipedia - 2023Computing
Past a thousand qubits
IBM's Condor reaches 1,121 superconducting qubits, while its modular Heron chip shifts the focus toward quality and error rates.
Wikipedia - 2024Cryptography
The first post-quantum standards are final
On 13 August NIST publishes FIPS 203 (ML-KEM), FIPS 204 (ML-DSA) and FIPS 205 (SLH-DSA), the first finished post-quantum standards.
Wikipedia - 2024Computing
Google's Willow crosses the error-correction threshold
Google reports that adding qubits to its Willow chip lowered the logical error rate, an important below-threshold milestone for quantum error correction.
Wikipedia - 2025Computing
Microsoft's Majorana 1
Microsoft announces Majorana 1, a chip built on its topological-qubit approach, an early and closely scrutinized claim.
Wikipedia - 2025Cryptography
NIST adds a backup KEM
NIST selects the code-based scheme HQC as a second key-encapsulation standard, for diversity beyond the lattice-based ML-KEM.
Wikipedia