Einstein CentennialAnswer
Has Einstein’s relativity ever failed a test?
What happened to OPERA's 2011 faster-than-light claim, how relativity is tested, and why successful measurements do not prove every possible prediction.
THE QUESTION LIBRARY EINSTEIN CENTENNIAL
Why does quantum physics seem so weird, even to physicists?
Why electrons can produce wave-like patterns, what two-slit experiments show, and why a physical measurement differs from a conscious observer.
THE SHORT ANSWER
Quantum physics seems weird because the rules that describe electrons and photons do not fit the familiar picture of tiny balls following definite paths. Individual detections are localized, yet repeated experiments can produce wave-like interference. Quantum theory gives precise probabilities for those results. Its strangeness is a challenge to everyday intuition, not permission to claim that anything is possible.
- Localized detections can build a wave-like pattern.
- Quantum amplitudes combine before probabilities are calculated.
- Physical measurement does not require consciousness.
WHAT WE DON’T KNOW YET
This answer does not settle competing interpretations of quantum reality or claim that familiar pictures explain every quantum process.
WHAT WOULD CHANGE THIS ANSWER
A reproducible experimental disagreement with the calculated probabilities, after apparatus and analysis checks, would change the theory's tested scope.
Quantum physics seems weird because the rules that describe electrons and photons do not fit the familiar picture of tiny balls following definite paths. Individual detections are localized, yet repeated experiments can produce wave-like interference. Quantum theory gives precise probabilities for those results. Its strangeness is a challenge to everyday intuition, not permission to claim that anything is possible.
THE LONG ANSWER
THE LONG ANSWER · ABOUT 2 MINUTES
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Keep asking
Has Einstein’s relativity ever failed a test?
Relativity has survived the tests discussed here; an apparent failure is not automatically a confirmed failure.
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God Plays Dice answers big questions in plain words, with sources and one of six honest labels.
Words worth knowing (2)
- interference
- Reinforcement or cancellation between wave-like amplitudes.
- wave function
- A mathematical description used to calculate quantum measurement probabilities.
Sources & further reading
(4) · Checked Oct 5, 2026
- DOE Explains…Quantum Mechanics ↗U.S. Department of Energy, Office of ScienceOfficial explanation of wave-particle duality, wave functions, and quantum technologies.
- Controlled double-slit electron diffraction ↗Bach, Pope, Liou and Batelaan; New Journal of PhysicsOriginal experiment, published in 2013; individual electron detections build the diffraction distribution.
- The Feynman Lectures on Physics, III.1: Quantum Behavior ↗California Institute of Technology; Feynman, Leighton and SandsOriginal teaching account of amplitudes, probabilities, and two-slit comparisons; historical interpretation claims are not treated as settled modern conclusions.
- Measurement-induced decoherence and information in double-slit interference ↗Kincaid, McLelland and Zwolak; American Journal of Physics; NIST2016 theoretical model relates acquisition of path information to loss of interference.
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CONTINUE THE THREAD
Where this question leads.
Einstein CentennialAnswer
Can quantum entanglement send messages faster than light?
Einstein called it “spooky action at a distance,” and the matching is real, but here is why nobody can use it to send a message faster than light.
Einstein CentennialAnswer
Did Einstein lose his argument that God does not play dice?
A century after his famous letter to Max Born, experiments have ruled on part of Einstein’s hope, while the question of dice itself is still argued.