MadSci Network: Physics

Re: Have scientists documented spontaneous creation of matter in vaccum?

Area: Physics
Posted By: Georg Hager, Grad student Theorie III
Date: Wed Mar 12 02:22:33 1997
Message ID: 857076005.Ph

Dear Mary!

I suppose that what you are referring to is the recent experimental confirmation of the Casimir Effect with amazing accuracy. The `original' Casimir effect is the appearance of a tiny force between two parallel, conducting plates which are a small distance apart.
What has this got to do with creation of matter or energy out of the vacuum? In order to understand this you have to realize that today's physicists' view of the `vacuum' is different from the usual meaning of the word. Due to the laws of quantum mechanics, it is possible for elementary particles to be created `from nothing', interact for a short period of time and then annihilate into the void. This happens everywhere, all the time. The vacuum is teeming with activity on a sub-microscopic scale! Now, you might have heard that particles can behave like waves under certain circumstances, and that's where the Casimir effect emerges:
Placing a `chunk' of vacuum between a pair of parallel conducting plates subjects the vacuum to boundary conditions. As a consequence, waves with a wavelength which is larger than twice the distance between the plates cannot exist there. So, the activity of the vacuum I described above is limited between the plates. It is limited insofar as very low-energy particles (those with large wavelengths) are excluded. On the other hand, they are not excluded outside the plates. Hence it follows that there is, in a sense, more `teeming' outside the plates than inside, and this leads to the observed attractive force.

The experimental confirmation to about 5% accuracy was recently done by Steve Lamoreaux at the U of Washington. To get more insight into theory and experiment, take a look at this bibliography of the Casimir Effect.

Hope that helps,

Current Queue | Current Queue for Physics | Physics archives

Return to the MadSci Network

MadSci Home | Information | Search | Random Knowledge Generator | MadSci Archives | Mad Library | MAD Labs | MAD FAQs | Ask a ? | Join Us! | Help Support MadSci

MadSci Network
© 1997, Washington University Medical School