What is Virtual particle?
A '''virtual particle''' is a short-lived particle. It is similar to an ordinary particle, but cannot be directly detected.<ref>{{cite web | url=https://www.symmetrymagazine.org/article/july-2009/60-seconds-virtual-particles | title=Virtual particles }}</ref> Virtual particles can suddenly appear in the [[vacuum]] and then quickly disappear. They can also be emitted by real particles and interact with other particles. In both cases their lifetime is limited by the [[Heisenberg's uncertainty principle]]. They interact also with [[macroscopic]] objects and, for example, cause the attraction of two metal plates in a vacuum. This [[phenomenon]] is called the [[Casimir effect]] (predicted by Hendrik Casimir in 1948) ==References== {{reflist}} [[Category:Quantum mechanics]] {{physics-stub}}