Expansion speeding up

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Re: Expansion speeding up

Postby david48 » Fri Sep 04, 2015 4:42 pm

Gfamily, your comments are very valuable. They are helping me to get a grip on this subject.
Especially about "red light". Now it seems to me, that there is no such thing, really, as "red light".

All Light is just photons, doing their own thing. That's to say, travelling at velocity "c".
These photons may appear to us humans to be in different "colours". Such as "red". The "red" colour can described as the result of "refraction". But perhaps it's better described as " slowing down". And this can result from two causes:

1. The photons are coming to us across an increasing distance, so their time of arrival gets slowed down by distance.

2. The photons are coming to us across an obstructing medium, such as glass or hydrogen, so their time of arrival gets slowed down by the obstruction of the intervening glass/hydrogen molecules.

Both causes seem possible. So I can't see why the astronomical "redshift" must be ascribed only to cause 1 - ie distance - rather than to cause 2, ie obstruction by interstellar gas, dust, ice particles and so on. Which we know, are abundant in the Universe.

I'd greatly appreciate your further thoughts and comments, thanks!
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Re: Expansion speeding up

Postby Gfamily2 » Fri Sep 04, 2015 6:51 pm

david48 wrote:Gfamily, your comments are very valuable. They are helping me to get a grip on this subject.
Especially about "red light". Now it seems to me, that there is no such thing, really, as "red light".

All Light is just photons, doing their own thing. That's to say, travelling at velocity "c".
These photons may appear to us humans to be in different "colours". Such as "red". The "red" colour can described as the result of "refraction". But perhaps it's better described as " slowing down". And this can result from two causes:

1. The photons are coming to us across an increasing distance, so their time of arrival gets slowed down by distance.

2. The photons are coming to us across an obstructing medium, such as glass or hydrogen, so their time of arrival gets slowed down by the obstruction of the intervening glass/hydrogen molecules.

Both causes seem possible. So I can't see why the astronomical "redshift" must be ascribed only to cause 1 - ie distance - rather than to cause 2, ie obstruction by interstellar gas, dust, ice particles and so on. Which we know, are abundant in the Universe.

I'd greatly appreciate your further thoughts and comments, thanks!


I don't think that'll work because I'm afraid to say there's so much you clearly don't understand - and learning via conversation takes such a lot of time and effort.
I suggest you get yourself a few basic books on Physics, Astronomy and Cosmology and make notes on what they say. Please don't try to think of alternatives to the theories described, because it's clear that your understanding is not up to it. When you understand the theories described, you can then consider alternatives.
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Re: Expansion speeding up

Postby david48 » Fri Sep 04, 2015 7:45 pm

When I suggested that the Red-Shift might not be a distance effect, you said that the theory says it is. So my understanding must be wrong.

You said "Please don't try to think of alternatives to the theories described"


This is deplorable. If everyone took that approach, wouldn't Science be dead?
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Re: Expansion speeding up

Postby Gfamily2 » Fri Sep 04, 2015 7:59 pm

david48 wrote:When I suggested that the Red-Shift might not be a distance effect, you said that the theory says it is. So my understanding must be wrong.

You said "Please don't try to think of alternatives to the theories described"


This is deplorable. If everyone took that approach, wouldn't Science be dead?

No, people thinking they know better when they don't even understand the existing theories is deplorable.
Ever heard of not trying to run before you can walk?

What's your objection to learning about the existing theory?
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Re: Expansion speeding up

Postby david48 » Fri Sep 04, 2015 8:20 pm

The objection is this: if you learn too much about the existing theory, it makes it harder for you to consider any alternative.

The existing theory fills your mind, and when your mind is full, it gets resistant to admitting anything new.

That's life. Once we are satisfied with a theory, we don't like to entertain any idea which may disturb this satisfaction.

For example, filled minds intensely resist the idea that the cosmological Red-Shift might be not be a distance-indicator.

As I think has been amply demonstrated here already :|
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Re: Expansion speeding up

Postby Gfamily2 » Fri Sep 04, 2015 10:10 pm

david48 wrote:The objection is this: if you learn too much about the existing theory, it makes it harder for you to consider any alternative.

The existing theory fills your mind, and when your mind is full, it gets resistant to admitting anything new.

That's life. Once we are satisfied with a theory, we don't like to entertain any idea which may disturb this satisfaction.

For example, filled minds intensely resist the idea that the cosmological Red-Shift might be not be a distance-indicator.

As I think has been amply demonstrated here already :|

A little learning is a dangerous thing. Sorry, but you're not even dangerous yet.
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Re: Expansion speeding up

Postby david48 » Sun Sep 06, 2015 5:11 pm

A little learning may indeed be a dangerous thing for existing theories. Because the paucity of learning about existing theories, may sometimes engender new thoughts, which lead to the overthrow of the theories.

For example, suppose Isaac Newton had been thoroughly taught about Aristotle's Greek theory of physics. Where stones fall faster when they're heavier. Would such an indoctrinated Newton have been able to arrive at the true mathematical Theory of Gravity? Probably not, because he would've been sucked in by the false Aristotle theory.

This shows that it is not wise to learn too much about existing theories. It prejudices the mind. And so can lead the mind to believe in blatantly absurd theories, such as Dark Matter, and 9-Dimensional Strings.

The scientific mind should be kept open, but not get obsessed with fashionable theories.
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Re: Expansion speeding up

Postby Gfamily2 » Sun Sep 06, 2015 5:44 pm

david48 wrote:A little learning may indeed be a dangerous thing for existing theories. Because the paucity of learning about existing theories, may sometimes engender new thoughts, which lead to the overthrow of the theories.

For example, suppose Isaac Newton had been thoroughly taught about Aristotle's Greek theory of physics. Where stones fall faster when they're heavier. Would such an indoctrinated Newton have been able to arrive at the true mathematical Theory of Gravity? Probably not, because he would've been sucked in by the false Aristotle theory.

This shows that it is not wise to learn too much about existing theories. It prejudices the mind. And so can lead the mind to believe in blatantly absurd theories, such as Dark Matter, and 9-Dimensional Strings.

The scientific mind should be kept open, but not get obsessed with fashionable theories.

OK, so in your view what is meant by 'red shift', and how is it measured?
We can then see if you understand the problem.

In your preferred hypothesis, what physical cause of the red shift, and what leads to different amounts of red shift for different galaxies. Is the 'reddening' different depending on the original frequency of the emitted light? How do you explain blue shift seen for some galaxies?

Can you quantify the amount of intergalactic gas required to produce the observed red shift?

Crucially, what experiments can you suggest that would show that your preferred hypothesis gives a better correspondence to the observations than the current model?
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Re: Expansion speeding up

Postby david48 » Sun Sep 06, 2015 7:34 pm

Gfamily2 wrote:
david48 wrote:A little learning may indeed be a dangerous thing for existing theories. Because the paucity of learning about existing theories, may sometimes engender new thoughts, which lead to the overthrow of the theories.

For example, suppose Isaac Newton had been thoroughly taught about Aristotle's Greek theory of physics. Where stones fall faster when they're heavier. Would such an indoctrinated Newton have been able to arrive at the true mathematical Theory of Gravity? Probably not, because he would've been sucked in by the false Aristotle theory.

This shows that it is not wise to learn too much about existing theories. It prejudices the mind. And so can lead the mind to believe in blatantly absurd theories, such as Dark Matter, and 9-Dimensional Strings.

The scientific mind should be kept open, but not get obsessed with fashionable theories.

OK, so in your view what is meant by 'red shift', and how is it measured?
We can then see if you understand the problem.

In your preferred hypothesis, what physical cause of the red shift, and what leads to different amounts of red shift for different galaxies. Is the 'reddening' different depending on the original frequency of the emitted light? How do you explain blue shift seen for some galaxies?

Can you quantify the amount of intergalactic gas required to produce the observed red shift?

Crucially, what experiments can you suggest that would show that your preferred hypothesis gives a better correspondence to the observations than the current model?


Thanks Gfamily, I will reply to some of your points as follows:

1. The physical cause of the "Red-Shift" may be interstellar gas and dust, which slows down light, so producing a "reddening" effect.

2. The different amounts of "reddening" observed in galaxies, may be caused by the different amounts of gas and dust between us, and the galaxy. The further away the galaxy is, the more gas and dust there is between us and the galaxy. Which makes more reddening. This does NOT necessarily involve any "expansion". It could be just a static distance effect.

3. As regards the "blue-shift" - isn't this only observed in close galaxies such as M.31. This galaxy is so close to our Milky Way, only about 2+ million light-years away. So the interstellar gas between the two galaxies, may be be getting sucked by gravity into each of them. Thereby thinning out the gas between them. The thinner gas would reduce the "red-shift", and we might see this, by contrast, as a "blue-shift"?
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Re: Expansion speeding up

Postby Gfamily2 » Sun Sep 06, 2015 9:50 pm

You've not said how you think this red shift is measured. Please explain this first.

Now, why do you say that gas and dust would slow down light ?

How much does the light slow down by - lots or just a little? Typically, how much slower do you think light slows down, and does the light get progressively slower and slower, or does it just slow down when it enters the 'gas and dust'? How would you prove this?

How are the 'slowing down' and the 'red shift' related?
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