Learn more physics!
OK so i know that electromagnetic fields wont bend visible light, but is there a way to use said fields to confine something else that is lightweight and "produceable" (like ions or electrons?) into a specific field of space and "collect" them or in some other way make them "dense"?
- Mark (age 22)
The question you ask happens to be crucial for the future of
civilization. We need some large-scale long lasting source of usable
energy. Nuclear fusion is perhaps the only such source we know of
capable of sustaining a very large human population (like ours) for
thousands of years. The main method by which people are attempting to
achieve controlled nuclear fusion involves using magnetic bottles to
trap a plasma containing the ions whose collisions create the fusion.
These bottles certainly work for short times, etc. Whether they can be
made to work for long enough times for hot enough plasmas to run useful
fusion reactors remains to be seen.
On the more useless but still interesting end of the spectrum,
non-static electromagnetic fields are used to trap neutral atoms in
space. Sodium is one of the more popular ones because it has strong
absorption/emission lines. By shining appropriately tuned laser beams
(with frequencies just below the sodium line) in opposite directions in
three dimensions, you can create a little trap for sodium atoms. This
trap can cool the atoms down to fantastically low temperatures too. If
a sodium atom is traveling towards one of the lasers, the laser light
will be Doppler blueshifted closer to the absorption line and more
scattering of the photons from that laser will occur, pushing the
sodium atom back away from the laser. By doing this, you can slow down
atoms so much they condense to form a Bose-Einstein condensate (there
are more tricks needed to get the temperature low enough to do this).
See this link
(republished on 07/13/06)
Follow-up on this answer.