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Re: DOES LIGHT MOVE IN A STRAIGHT LINE ??

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  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

#373575 — Re: DOES LIGHT MOVE IN A STRAIGHT LINE ??

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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#373579

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.

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#373611

Kathleen Winder 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.

What does FR mean? Did you want to write GR? Then your statement is 
wrong, because Dark Energy and Dark Matter are concepts within the 
framework of GR: Dark Matter contributes to the energy-momentum tensor 
of the cosmic medium in the same way like dusty bright matter, with 
energy density rho > 0 and pressure p ~ 0 (i.e. |p| << rho), Dark Energy 
contributes with rho > 0 and p < -rho/3 (i.e. with p = -rho, then Dark 
Energy is equivalent to a cosmological constant).

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#373630

Gregor Scholten wrote:

> Kathleen Winder 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.
> 
> What does FR mean? Did you want to write GR? Then your statement is
> wrong, because Dark Energy and Dark Matter are concepts within the
> framework of GR: Dark Matter contributes to the energy-momentum tensor
> of the cosmic medium in the same way like dusty bright matter, with
> energy density rho > 0 and pressure p ~ 0 (i.e. |p| << rho), Dark Energy
> contributes with rho > 0 and p < -rho/3 (i.e. with p = -rho, then Dark
> Energy is equivalent to a cosmological constant).

Therefore you must have them additional to GR, in order to avoid the 
wrongness of GR, by only applying GR. Kathleen is perfectly right, and you 
are wrong, insinuating outrageously that Kathleen should be wrong. Yes, F 
and G are closely located. Surely was a typo, Einstein.

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#373638

it goes around venetians blinds.

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