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Author Topic: Is there a red shift anomaly  (Read 2096 times)

Offline jeffreyH

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Is there a red shift anomaly
« on: 21/02/2014 05:45:15 »
We look at the Hubble expansion data and see the universe as expanding more rapidly but consider this. If we move to a point in space 1000 ly away and run the same Hubble sequence we will see things further away moving more quickly than those nearer. If we move yet another 1000 ly away we will also see things further away moving more quickly than those nearer. At any point in the universe at a point 13 billion years into the universes evolution this will be true. In other words the universe is actually slowing down with time and in x billion years time we should see some galaxies far away becoming less red shifted and those nearer becoming blue shifted. This all works because there is no special frame of reference according to relativity.
« Last Edit: 21/02/2014 05:47:16 by jeffreyH »


 

Offline jeffreyH

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Re: Is there a red shift anomaly
« Reply #1 on: 21/02/2014 06:14:38 »
This site has the type 1a supernova data and the Hubble plot. The main point to note is the clustering of the nova data. More populous data appears nearer to the origin. I am unsure whether this was an artifact of the data or not.

http://www.asnsw.com/node/720
« Last Edit: 21/02/2014 06:34:31 by jeffreyH »
 

Offline jeffreyH

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Re: Is there a red shift anomaly
« Reply #2 on: 21/02/2014 06:26:26 »
Another thing to consider is that if the acceleration were truly increasing the distance between the local group galaxies and those further out would have extended significantly and be noticeable. The local group is around 3.1 Mpc. This list shows those and others from neighboring groups.

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

More data here.

http://en.wikipedia.org/wiki/List_of_galaxy_groups_and_clusters
« Last Edit: 21/02/2014 06:32:36 by jeffreyH »
 

Offline evan_au

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Re: Is there a red shift anomaly
« Reply #3 on: 21/02/2014 21:14:02 »
Quote
The main point to note is the clustering of the nova data. More populous data appears nearer to the origin. I am unsure whether this was an artifact of the data or not.
It is caused by the fact that more distant galaxies are fainter, so they need a bigger telescope (ideally space-based), observing for a longer period to detect them and estimate their distance.
It is much easier to estimate the distance and relative velocity of closer galaxies.
 

Offline jeffreyH

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Re: Is there a red shift anomaly
« Reply #4 on: 21/02/2014 22:58:02 »
Quote
The main point to note is the clustering of the nova data. More populous data appears nearer to the origin. I am unsure whether this was an artifact of the data or not.
It is caused by the fact that more distant galaxies are fainter, so they need a bigger telescope (ideally space-based), observing for a longer period to detect them and estimate their distance.
It is much easier to estimate the distance and relative velocity of closer galaxies.

Thanks for that it answers the question. Actually I am going to disprove my own assertion about expansion and will post the details. I do that sort of thing.
 

Offline jeffreyH

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Re: Is there a red shift anomaly
« Reply #5 on: 22/02/2014 01:11:59 »
If we imagine 3 objects 1) The earth object A 2) Object B 1 million ly away and 3) Object C 2 million ly away. The light from Object B will take 1 million years to reach us and the light from object C will take 2 million years. If we imagine pushing the light from both B and C back 1 million years to the point where object B was and then calculate where object B determines object C to be it should be at the same position determined by an earth observer but only 1 million ly from B. We can get the velocity of C from B's perspective by subtracting the velocity of B as oberved from earth from that of C. This will show that 1 million years ago B obervered C to be moving at a lower velocity relative to itself. We can carry on this procedure back billions of years and should see a general slowing of expansion. How does this interpretation fit with the big bang theory? What would we see at the end of the inflationary period?

It would be interesting to see if the velocity of C seen by B matches the velocity of B as seen from earth 1 million ly later.
« Last Edit: 22/02/2014 01:21:38 by jeffreyH »
 

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Re: Is there a red shift anomaly
« Reply #5 on: 22/02/2014 01:11:59 »

 

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