Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!mips!dimacs.rutgers.edu!aramis.rutgers.edu!planchet.rutgers.edu!nanotech From: dietz@cs.rochester.edu (Paul Dietz) Newsgroups: sci.nanotech Subject: Re: Near abs. 0 for $350 Message-ID: Date: 11 Jun 91 01:24:58 GMT Sender: nanotech@planchet.rutgers.edu Organization: Computer Science Department University of Rochester Lines: 34 Approved: nanotech@aramis.rutgers.edu (This has nothing much to do with nanotechnology, but I'm posting the followup here because the original message was here.) This laser-cooling scheme sounds interesting, especially if they can produce Bose-condensed collections of atoms and/or ions. The rate of a transition that puts a boson into a state already occupied by n identical bosons is multiplied by a factor of (n+1). For example, the rate of decay of an electronically excited atom in a laser amplifier can be much faster than its rate of spontaneous emission. Similarly, radioactive decay should also be accelerated by this effect if the decayed atom were to be added to an already large bose-condensed collection of identical atoms or ions. This is true even for non-electromagnetic decays, since there is nothing that says the boson must be a photon. One would have to arrange it so that the addition of the decayed atom to the bose-condensed state is allowed kinematically; i.e., recoil would have to be countered or the decay would have to involve two or more particles (for example, beta decay with the electron and neutrino emitted with equal but opposite momenta). This is a serious problem, since the energy of the bose-condensed atoms will be extremely small, on the order 10^-10 eV or less. That will lead to a very large reduction in the rate of the transition, since most decays would send the decayed atom into some other state. However, "n" is potentially very large. It would be interesting indeed if a practical means could be found to accelerate radioactive decay. Paul F. Dietz dietz@cs.rochester.edu