Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > sci.physics.relativity > #373579

Re: DOES LIGHT MOVE IN A STRAIGHT LINE ??

Cross-posted to 2 groups.

Show all headers | View raw

Kathleen Winder wrote:

> Rich L. wrote:
> 
>> Even if NASA did have an interstellar project, GR is not required to go
>> between stars in our galaxy.  It would be required if traveling close
>> to a black hole (either a stellar size black hole or the super massive
>> one at the center of our galaxy).  But we don't have the technology to
>> go to any such place right now.
> 
> Not so fast. To calculate anything at the galactic scale, you need not
> only FR, but also up to 96% Dark Energy and Dark Matter. Without these
> everything is wrong.
> 
> [Moderator's note: Dark energy can probably be neglected on galactic
> scales.  As for dark matter then, yes, if calculating a trajectory, one
> would have to take it into account, but we don't know what it is and
> exactly how it is distributed.  Within the solar system, one can
> calculate trajectories taking only the major bodies into account, and
> essentially travel on ballistic trajectories (i.e. little or no
> correction along the way).  This wouldn't be feasible for galactic-scale
> travel, even if we knew the mass distribution.  -P.H.]

This was a very big note, not only a note. Actually is not a note, and 
should not be confused with a note.

Back to sci.physics.relativity | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

Re: DOES LIGHT MOVE IN A STRAIGHT LINE ?? Kathleen Winder <katwin@mcgatlin.org> - 2016-01-09 15:48 +0000
  Re: DOES LIGHT MOVE IN A STRAIGHT LINE ?? Carmine Portacio <carpo@trilogybearing.org> - 2016-01-09 16:31 +0000
  Re: DOES LIGHT MOVE IN A STRAIGHT LINE ?? Gregor Scholten <g.scholten@gmx.de> - 2016-01-10 09:06 +0100
    Re: DOES LIGHT MOVE IN A STRAIGHT LINE ?? Carmine Portacio <carpo@trilogybearing.org> - 2016-01-10 15:42 +0000
      Re: DOES LIGHT MOVE IN A STRAIGHT LINE ?? The Starmaker <starmaker@ix.netcom.com> - 2016-01-10 10:50 -0800

csiph-web