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Blob
2006-Oct-09, 09:23 AM
Are virtual particles really constantly popping in and out of existence? Or are they merely a mathematical bookkeeping device for quantum mechanics?

Virtual particles are indeed real particles. Quantum theory predicts that every particle spends some time as a combination of other particles in all possible ways. These predictions are very well understood and tested.
Quantum mechanics allows, and indeed requires, temporary violations of conservation of energy, so one particle can become a pair of heavier particles (the so-called virtual particles), which quickly rejoin into the original particle as if they had never been there. If that were all that occurred we would still be confident that it was a real effect because it is an intrinsic part of quantum mechanics, which is extremely well tested, and is a complete and tightly woven theory--if any part of it were wrong the whole structure would collapse.

Read more (http://www.sciam.com/askexpert_question.cfm?articleID=0004D0F8-772A-1526-B72A83414B7F0000&catID=3&topicID=13)

Cugel
2006-Oct-09, 10:13 AM
How about Hawking radiation? That is a black hole emitting energy, slowly evaporating over time, so to speak. I thought this was only possible because of the virtual particles you mentioned. If Hawking radiation is an observed phenomena (I don't know) it would proof the existence of virtual particles. But is it? Or is it just a theoretical deduction, based on the theory of virtual particles (or quantum mechanics).

Blob
2006-Oct-09, 12:02 PM
Hum,
when i/someone can get the search function to work on the forum i`ll post a few links to Hawking radiation...