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The observed red shifts in Galaxies, Has Time been taken into account?
The further out we see into the universe, the greater the red shift we observe. Which, we attribute the Galaxies moving faster away from us. The further away the Galaxy, the greater the observed red-shift.
A Galaxy which may be 12 billion light years away has a greater red shift than one which is 4 billion light years away. To conclude that the universe is expanding and accelerating is perfectly understandable if (C) was infinitely fast.
However, we cannot look out into the universe without looking back into time.
When observing the red shifts and we take into account time, could this indicate that the expansion was instead of speeding up it is slowing down.
(If 12 billion years ago the Galaxies were moving faster away from us compared with 4 billion years ago.)
Hope this makes sense.
Ima: When a photon hits a meterial it is absorbed and a new photon is released
6 Answers
- Brigalow BlokeLv 75 years agoFavorite Answer
C does not have to be infinitely fast, it just has to be C. When any object moves away from you, you see the light that left it in when it was in position X. But in the time that the light took to arrive at your eye, the object has moved further away. This is true whether it is a distant galaxy or a car. In the case of a car, the extra distance may be less than a millimetre. In the case of a galaxy, which is moving faster and started off further away, the extra distance is considerable.
The acceleration of expansion is based on observations of dozens of a particular type of supernova (1A) at various distances over several years by two different teams.
- Anonymous5 years ago
Your premise is based on three unwarranted assumptions:
1. Red shift is caused by Doppler effect.
2. Distance can be estimated accurately by the apparent brightness of stars.
3. All stars of the same type according to the Hertzsprung-Russell diagram are the same absolute brightness.
The fallacy of the Hertzsprung–Russell diagram is that it is based on brightness and temperature, and then it is used to define brightness and temperature: a circular definition.
If the H-R diagram is not valid, then distance estimates are nothing more than guesses.
The fallacy of Doppler effect is that there are other causes which have not been considered.
The notion that red shift indicates distance is disproved by observing high Z objects in front of low Z objects, and some pairs being connected by bridges of matter.
- cosmoLv 75 years ago
Yes, all those effects are taken into account. See, for example, the chapter on high-redshift galaxies in Weinberg's "Gravitation and Cosmology".
- 5 years ago
Alan. If light interacted with MATERIAL, it would give up its energy and no longer be a photon. The end of its life, so to speak. Like light hitting your hand. That's the end of that photon. Light can bend due to magnetic force, but only to change it's directory, not its velocity.
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- Anonymous5 years ago
Interesting idea. I have often thought about the possibility of the light losing energy and so decreasing in frequency as it travels greater distances and interacts with interstellar material.
