EPR
Abbreviation with 4 meanings
| Stands for | Einstein-Podolsky-Rosen (paradox) |
|---|---|
| Meanings | 4 |
| Categories | Science & Engineering |
EPR has four meanings. The most common are Einstein-Podolsky-Rosen (paradox) (physics) and Electron paramagnetic resonance (chemistry); it can also stand for European Pressurized Reactor and Extended producer responsibility.
Meanings of EPR at a glance
| # | EPR stands for | Context |
|---|---|---|
| 1 | Einstein-Podolsky-Rosen (paradox) | Science & Engineering › Physics |
| 2 | Electron paramagnetic resonance | Science & Engineering › Chemistry |
| 3 | European Pressurized Reactor | Science & Engineering › Energy |
| 4 | Extended producer responsibility | Science & Engineering › Environmental |
1. Einstein-Podolsky-Rosen (paradox)
Science & Engineering · Physics Abbreviations
Thought experiment published in 1935 by Albert Einstein, Boris Podolsky and Nathan Rosen, arguing that quantum mechanics must be incomplete because entangled particles appear to influence each other instantly at a distance. It launched the study of quantum entanglement.
Example: Bell's theorem turned the EPR argument into a testable prediction about correlations between particles.
John Bell showed in 1964 that no local "hidden variable" theory can reproduce all quantum predictions, and experiments by John Clauser, Alain Aspect and Anton Zeilinger confirmed quantum theory, earning the 2022 Nobel Prize in Physics. Einstein called entanglement "spooky action at a distance." In chemistry EPR stands for electron paramagnetic resonance.
2. Electron paramagnetic resonance
Science & Engineering · Chemistry Abbreviations
Spectroscopy that detects unpaired electrons by placing a sample in a magnetic field and measuring microwave absorption. EPR is used to study free radicals, transition-metal complexes and defects in materials, to date tooth enamel and to reconstruct radiation doses received by people after accidents.
Example: EPR spectra of irradiated alanine pellets were used to verify the delivered dose.
Also called electron spin resonance (ESR); the two names describe the same technique. Yevgeny Zavoisky first observed the effect in 1944 in Kazan. It is closely analogous to NMR but probes electrons rather than nuclei, and uses microwave rather than radio frequencies, typically around 9-10 GHz.
3. European Pressurized Reactor
Science & Engineering · Energy Abbreviations
Large third-generation pressurized water reactor design of about 1,600 megawatts developed by Framatome and Siemens, later marketed as the Evolutionary Power Reactor. EPRs operate in China, Finland and France, and two are under construction at Hinkley Point C in England.
Example: Finland's Olkiluoto 3 EPR began regular power production in 2023, about 14 years behind schedule.
Taishan 1 in China became the first EPR to operate commercially, in 2018. The French Flamanville 3 unit was connected to the grid in December 2024 after years of delays and cost overruns. In chemistry EPR means electron paramagnetic resonance, and in environmental policy extended producer responsibility.
4. Extended producer responsibility
Science & Engineering · Environmental Abbreviations
Policy approach that makes manufacturers responsible for the end-of-life management of their products, usually by funding collection and recycling. EPR programs cover packaging, electronics, batteries, tires, paint and mattresses in many countries.
Example: Under the new EPR law, brands selling packaged goods in the state must pay fees to fund recycling.
Germany's 1991 Packaging Ordinance and its Green Dot system pioneered packaging EPR. In the United States, Maine and Oregon passed the first packaging EPR laws in 2021. Fees are often adjusted to reward recyclable designs. In chemistry EPR means electron paramagnetic resonance.
Related abbreviations
More physics abbreviations
- EM – Electromagnetic
- EMF – Electromagnetic field
- EMP – Electromagnetic pulse
- EMR – Electromagnetic radiation
- EUV – Extreme ultraviolet
- FBD – Free-body diagram
- FCC – Future Circular Collider
- FWHM – Full width at half maximum
See all 68 physics abbreviations →