From: '''newspam'''@nonad.co.uk   
      
   On 09/02/2026 17:48, john larkin wrote:   
   > If I reply to posts from the pointy-ear guy, they go to sci.astro,   
   > even though his posts are in sci.electronics.design.   
      
   There is nothing odd about it at all. He has set followups to sci.astro   
   which is now a hell hole where all the lunatic fringe nutters hang out.   
      
   sci.astro.amateur and .moderated was created to separate the deranged   
   nutters with their NEW THEROY (sic) OF THE UNIVERSE all in CAPS from   
   people who wanted to talk about astronomy. It worked for a while too.   
      
   Your Usenet client is doing *exactly* what it is supposed to do.   
      
   > This is agent/eternal september.   
   >   
   > The issue was   
   >   
   >> 3. By contrast to light, gravitational waves are quadrupole waves that are   
   >>    only emitted when the spacetime curvature changes in a non-spherically   
   >>    symmetric way.  They are also emitted by objects and systems which do not   
   >>    emit light.   
   >   
   > Suppose that somewhere out in free space a cannonball somehow   
   > appeared. Wouldn't that create a symmetric, spherical gravitational   
   > wave?   
      
   E = mc^2   
      
   It is not possible to violate conservation of mass energy in the way   
   that you propose with enough mass to have an appreciable gravitational   
   effect. Quantum mechanics uncertainty principle puts very strict bounds   
   on how much mass/energy you can spirit into existence and for how long.   
      
   The simplest system that can create gravitational waves is a close   
   binary star system. Ones with two pulsars in are very handy tests of   
   relativity. I was at the seminar where that discovery was announced.   
      
   https://en.wikipedia.org/wiki/Hulse–Taylor_pulsar#Use_as_a_tes   
   _of_general_relativity   
      
   https://en.wikipedia.org/wiki/PSR_J0737−3039   
      
   LIGO sees them only in the very final stages of orbital when they go   
   down the plug hole with a big crunch.   
      
   > Microphones some distance away, in any direction, would hear a click   
   > some time later.   
      
   If you could do it and on a large enough scale then it would perturb the   
   orbits of objects but only after enough time has elapsed for its   
   influence to reach them (and it would switch on suddenly in a step).   
      
   However, conservation of mass-energy prevents it from being possible.   
      
   This was always the problem with Newtonian gravitation - to avoid having   
   the Earth spiral into the sun in classical mechanics the speed of   
   Newtonian gravity has to be infinite. IOW It has to be an exactly   
   central force between the two centres of mass at every instant in time.   
      
   GR gets around this by redefining what is a straight line so that the   
   influence of the sun is handled by the curvature of spacetime itself.   
      
   --   
   Martin Brown   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)