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Author Topic: Is Hubble red-shift a change in vision?  (Read 1425 times)

Offline Thebox

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Is Hubble red-shift a change in vision?
« on: 16/05/2016 07:01:30 »
Is the red-shift we observe simply a change in vision?


 

Offline Atomic-S

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Re: Is Hubble red-shift a change in vision?
« Reply #1 on: 16/05/2016 07:25:05 »
No, it is detected also by instruments having nothing to do with anyone's eyesight.
 

Offline Thebox

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Re: Is Hubble red-shift a change in vision?
« Reply #2 on: 16/05/2016 15:48:25 »
No, it is detected also by instruments having nothing to do with anyone's eyesight.


What do you mean it is detected by instruments?   

How would an instrument know it was the ''colour'' red?


Isn't Hubble a telescope that uses vision?

Do we not see through the ''eye'' of Hubble and visually observe the red-shift?

« Last Edit: 16/05/2016 15:52:37 by Thebox »
 

Offline Colin2B

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Re: Is Hubble red-shift a change in vision?
« Reply #3 on: 16/05/2016 16:15:42 »
How would an instrument know it was the ''colour'' red?
Measure the frequency
Isn't Hubble a telescope that uses vision?
There isn't a human eye looking down the end.

I think you need to be clearer what you mean by "change in vision"
Also, you might want to consider what might cause such a change, unless you are suggesting it is all in the imagination!
 

Offline Thebox

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Re: Is Hubble red-shift a change in vision?
« Reply #4 on: 16/05/2016 17:08:00 »

Measure the frequency

How do you measure the frequency of something that is very far away?   

Have you got ''probes'' out there?


Quote
There isn't a human eye looking down the end.

I think you need to be clearer what you mean by "change in vision"
Also, you might want to consider what might cause such a change, unless you are suggesting it is all in the imagination!


Obviously the Hubble does not have a human eye, but at the end of the ''line'' it is a human eye that observes the ''view''.

A change in vision is that the redshift is different to the ''surrounding'' light passing through space, my constant-'constant and the invisible light .

 

Online alancalverd

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Re: Is Hubble red-shift a change in vision?
« Reply #5 on: 16/05/2016 17:16:04 »



How do you measure the frequency of something that is very far away?   


You wait until it arrives, then measure it, using a spectrometer.
 

Offline Thebox

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Re: Is Hubble red-shift a change in vision?
« Reply #6 on: 16/05/2016 17:36:09 »




You wait until it arrives, then measure it, using a spectrometer.


Hmm you wait for  it to arrive, but is light not continuously arriving and also continuously being emitted from the observation ''point'' , how do you know the light that is arriving is the light from a distant ''object' , do you directly aim your spectrometer at the ''object''? 


Relative to the observer how do you  know the light is not red shifting this ''end''?   

Relativity states that if two observers  are in motion, neither observer can tell who is moving,  it all sounds a bit hmmmm to me.








 

Online alancalverd

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Re: Is Hubble red-shift a change in vision?
« Reply #7 on: 16/05/2016 18:33:31 »



Hmm you wait for  it to arrive, but is light not continuously arriving and also continuously being emitted from the observation ''point'' , how do you know the light that is arriving is the light from a distant ''object' , do you directly aim your spectrometer at the ''object''? 
We can estimate distance by astronomical parallax - worth a google!


Quote
Relative to the observer how do you  know the light is not red shifting this ''end''?
because we also observe blue shifts, and red shifts vary from object to object, so it seems more likely that the shift is connected with the source rather than the receiver.   

Quote
Relativity states that if two observers  are in motion, neither observer can tell who is moving,  it all sounds a bit hmmmm to me.
Nothing clever about it - just common observation. If you are in a train moving at constant speed, and you pass another train, you can't tell by looking at it which of you is moving at what speed - all you can measure is your relative speed. Same thing applies to converging aircraft in the absence of any other reference points: your air-to-air radar can only measure your speed relative to each other. That's the basis of relativity. It gets interesting when you discover that there is no fixed interstellar medium: all astronomical movement is relative. It's really very simple.


Incidentally "red" and "blue" don't just refer to perceived color. All photons are subject to frequency shift due to source movement (Doppler shift) or gravitational field gradient.
« Last Edit: 16/05/2016 18:36:38 by alancalverd »
 

Offline jeffreyH

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Re: Is Hubble red-shift a change in vision?
« Reply #8 on: 16/05/2016 19:29:58 »
Alan's last post sums it up nicely. You need to take these things in to make positive progress.
 

Offline Thebox

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Re: Is Hubble red-shift a change in vision?
« Reply #9 on: 16/05/2016 19:50:14 »


 because we also observe blue shifts, and red shifts vary from object to object, so it seems more likely that the shift is connected with the source rather than the receiver. 


Are you saying that the blue-shift or red-shift is observed at/of the observed point source?






 
 

 

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Re: Is Hubble red-shift a change in vision?
« Reply #9 on: 16/05/2016 19:50:14 »

 

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