Observer Effect (physics)
In science, the term observer effect refers to changes that the act of observation will make on a phenomenon being observed. This is often the result of instruments that, by necessity, alter the state of what they measure in some manner. A commonplace example is checking the pressure in an automobile tire; this is difficult to do without letting out some of the air, thus changing the pressure. This effect can be observed in many domains of physics.
The observer effect on a physical process can often be reduced to insignificance by using better instruments or observation techniques. However in quantum mechanics, which deals with very small objects, it is not possible to observe a system without changing the system, so the observer must be considered part of the system being observed.
Historically, the observer effect has been confused with the uncertainty principle.
Read more about Observer Effect (physics): Particle Physics, Electronics, Thermodynamics, Quantum Mechanics
Famous quotes containing the words observer and/or effect:
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—Viorica Butnariu, Rumanian student at Bucharest University. letter, Dec. 23, 1989, to American friend. Observer (London, Dec. 31, 1989)
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—Ernestine L. Rose (1810–1892)