Re: Sol-like system discovered...SETI new directions?

From: Robert J. Bradbury (bradbury@aeiveos.com)
Date: Thu Jul 10 2003 - 21:10:36 MDT

  • Next message: Robert J. Bradbury: "Re: Bostrom & Hanson in Article"

    On Thu, 10 Jul 2003 ABlainey@aol.com wrote:

    > This is also my view , that gravity being instantanious gives an unbeatable
    > method of information transfer. That is of course depending on the propgation
    > speed. Everything I have read thus far states that the propogation is
    > istantanious.

    Hmmmmm.... A google on "speed of gravity waves" yields:

    http://imagine.gsfc.nasa.gov/docs/ask_astro/answers/980905b.html
    http://physics.about.com/library/weekly/aa011503a.htm
    http://www.nature.com/nsu/030106/030106-8.html

    to which there appears to be an upstart challenge:

    http://www.lbl.gov/Science-Articles/Archive/Phys-speed-of-gravity.html

    So I would say that the balance of the conventional wisdom
    is that gravity propagates at the speed-of-light.

    It is also true that to get gravity waves one has to manipulate *very*
    large masses. That is *very* expensive relative to the manipulation
    of photons (which effectively have very low masses [based on E = mc^2]).

    Robert



    This archive was generated by hypermail 2.1.5 : Thu Jul 10 2003 - 21:21:27 MDT