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Re: DOES LIGHT MOVE IN A STRAIGHT LINE ??

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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.]

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Re: DOES LIGHT MOVE IN A STRAIGHT LINE ?? "Rich L." <ralivingston1952@charter.net> - 2016-01-07 15:50 +0100
  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 ?? Gregor Scholten <g.scholten@gmx.de> - 2016-01-10 09:06 +0100

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