>Casimir effect
>using ‘free’ energy borrowed from nothing
Vacuum energy pressure, like gravity, will bring the two plates together, but pulling them back apart will take energy (again, just like with gravity or even a spring), and so doesn't show much promise as a perpetual motion machine.
Your comment was marked dead (until I vouched for it). If a comment is dead, by default people can't see them unless they have "showdead" turned on in their preferences.
Your first two comments are not dead, your three most recent are (were).
I'm not sure why. You might email hn@ycombinator.com
Vacuum energy pressure, like gravity, will bring the two plates together, but pulling them back apart will take energy (again, just like with gravity or even a spring), and so doesn't show much promise as a perpetual motion machine.