Cannot redshift from distant objects be interpreted as gravitationalredshift, if the universe is wrapped around itself?

Redshift could be interpreted as if distant galaxies are moving away
from us, but can't it also be generated by the curvature of spacetime
itself?

Redshift can be caused by gravity when light is accelerated towards a
gravitational influence, and shouldn't light from distant galaxies be
following a curved path, if the entire universe is wrapped around
itself?

http://www.archania.org/optical_illusion.htm

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"Zanthius" wrote in message
...
| Redshift could be interpreted as if distant galaxies are moving away
| from us, but can't it also be generated by the curvature of spacetime
| itself?

Oh yeah, spacetime is curved up its own arsehole, you crank.
*plonk*

Dear Zanthius:

"Zanthius" wrote in message
...
Redshift could be interpreted as if distant galaxies
are moving away from us, but can't it also be
generated by the curvature of spacetime itself?

No, not exactly.

Redshift can be caused by gravity when light is
accelerated towards a gravitational influence,

Sorry, that is a *blue* shift.

and shouldn't light from distant galaxies be
following a curved path, if the entire universe is
wrapped around itself?

Yes, and no respectively.
http://www.astro.ucla.edu/~wright/cosmo_01.htm
http://www.astro.ucla.edu/~wright/cosmology_faq.html#z
http://www.astro.ucla.edu/~wright/doppler.htm

David A. Smith

On 6 Apr, 22:51, "N:dlzc D:aol T:com \(dlzc\)" wrote:
Sorry, that is a *blue* shift.

It is the light that is accelerated towards the gravitational
influence, not the source emitting light, and that will make the light
stretch to redshift, not contract to blueshift.

http://en.wikipedia.org/wiki/Gravitational_redshift

"Zanthius" wrote in message

On 6 Apr, 22:51, "N:dlzc D:aol T:com \(dlzc\)" wrote:
Sorry, that is a *blue* shift.

It is the light that is accelerated towards the gravitational
influence, not the source emitting light, and that will make the light
stretch to redshift, not contract to blueshift.

http://en.wikipedia.org/wiki/Gravitational_redshift

No, it must *gain* energy falling into a gravitational
field. It will blueshift falling in, and redshift
climbing out.

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"N:dlzc D:aol T:com (dlzc)" wrote in message
...
| Dear Zanthius:
|
| "Zanthius" wrote in message
| ...
| Redshift could be interpreted as if distant galaxies
| are moving away from us, but can't it also be
| generated by the curvature of spacetime itself?
|
| No, not exactly.
|
| Redshift can be caused by gravity when light is
| accelerated towards a gravitational influence,
|
| Sorry, that is a *blue* shift.
|
| and shouldn't light from distant galaxies be
| following a curved path, if the entire universe is
| wrapped around itself?
|
| Yes, and no respectively.
| http://www.astro.ucla.edu/~wright/cosmo_01.htm
| http://www.astro.ucla.edu/~wright/cosmology_faq.html#z
| http://www.astro.ucla.edu/~wright/doppler.htm
|
Right and wrong, irrespectively.

http://en.wikipedia.org/wiki/Gravitational_redshift

Well, this page only speaks about light climbing uphill or downhill a
gravitational field.

What about light orbiting the event horizon of a black hole? It won't
climb uphill or downhill, but it will experience a constant
acceleration towards the center of the black hole.

As far as I can see, when light is experiencing a constant
acceleration while orbiting the event horizon of a black hole, it
should be stretched by the vector pulling it towards the center of the
black hole, not contracted.

On 6 Apr, 23:16, "Greg Neill" wrote:
No, it must *gain* energy falling into a gravitational
field. It will blueshift falling in, and redshift
climbing out.

Yes, but what about light orbiting the event horizon of a black hole?

"Zanthius" wrote in message

http://en.wikipedia.org/wiki/Gravitational_redshift

Well, this page only speaks about light climbing uphill or downhill a
gravitational field.

What about light orbiting the event horizon of a black hole? It won't
climb uphill or downhill, but it will experience a constant
acceleration towards the center of the black hole.

Light won't orbit a black hole at the event horizon,
but it can a bit further out (r = 3*G*M/c^2 for a
non-rotating black hole, if I recall correctly).

As far as I can see, when light is experiencing a constant
acceleration while orbiting the event horizon of a black hole, it
should be stretched by the vector pulling it towards the center of the
black hole, not contracted.

If this were true then planets orbint stars in circular
orbits would have to constantly speed up (gain energy).

Redshift or blueshift only occurs if the light changes
position (height) in the gravitational potential.

"Zanthius" wrote in message

On 6 Apr, 23:16, "Greg Neill" wrote:
No, it must *gain* energy falling into a gravitational
field. It will blueshift falling in, and redshift
climbing out.

Yes, but what about light orbiting the event horizon of a black hole?

The same applies. It will either spiral in (blushift) or
spiral out (redshift). There are no stable free-fall
orbits near the event horizon.