Expansion speeding up

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Re: Expansion speeding up

Postby Gfamily2 » Thu Sep 10, 2015 6:32 pm

david48 wrote:Thanks Gfamily. Your posts are extremely valuable, in that they stimulate thinking. Which is what Science needs - clear thinking.

I would reply to some of your points as follows:

1. About the red-shift displayed in the spectra of distant galaxies, being caused by clouds of hydrogen gas. I've already explained in previous posts, that this is most likely caused simply by our having to view them through the gas. . The gas makes the light appear red-shifted.
Just as fog can cause terrestrial white lights to look yellowish, ie red-shifted, when viewed through the fog.

That's scattering, which is very different to when you were describing it as a refraction effect.

Which brings me back to the question I think I asked earlier - what is it that astronomers measure when they measure the 'red shift' of distant galaxies? You seem to think that they are measuring the different ratio of red and blue light in the spectrum - whereas they are actually measuring the shift in spectral lines in the spectrum. This is a doppler shift, not just some adjustment in the balance of the spectrum.

Like I've said - finding out about the problem is important. You may think it 'fills your mind, and when your mind is full it gets resistant to admitting anything new', but refusing to investigate doesn't help, because no matter what ideas you come up with, you have no way of determining whether your new ideas are good, bad or indifferent.
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Re: Expansion speeding up

Postby david48 » Thu Sep 10, 2015 8:10 pm

Gfamily, you're a formidable adversary, and probably a great loss to the legal profession! ;)

I admire that. Because in Science truth is paramount, and obfuscation of truth should be ruthlessly exposed by the kind of powerful cross-examination you're subjecting me to! I thought I could get away with vague waffle, but you are pinning me down.

On the point about the Red-Shift, may I come back after doing some research. Usually I don't do research, instead relying on my polymath memory. However in this case, I see that more work is required. Or I might just give up. Probably that's easier!
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Re: Expansion speeding up

Postby Gfamily2 » Thu Sep 10, 2015 11:18 pm

david48 wrote:Gfamily, you're a formidable adversary, and probably a great loss to the legal profession! ;)

I admire that. Because in Science truth is paramount, and obfuscation of truth should be ruthlessly exposed by the kind of powerful cross-examination you're subjecting me to! I thought I could get away with vague waffle, but you are pinning me down.

On the point about the Red-Shift, may I come back after doing some research. Usually I don't do research, instead relying on my polymath memory. However in this case, I see that more work is required. Or I might just give up. Probably that's easier!

Easier, schmesier. Get stuck into the research - you know it makes sense
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Re: Expansion speeding up

Postby david48 » Mon Sep 14, 2015 3:07 pm

I think you are so firmly convinced that the "Red Shift" is a distance effect, that no amount of argument to the contrary will make you change your mind. Your mind is completely "filled up" with the "distance" theory. To the extent that you won't admit any alternative theory. You've made your mind up, and so that's that.

But that's not Science.
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Re: Expansion speeding up

Postby Gfamily2 » Mon Sep 14, 2015 9:32 pm

Done any research yet?
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Re: Expansion speeding up

Postby david48 » Wed Sep 16, 2015 5:59 pm

Gfamily2 wrote:Done any research yet?


Thanks G, Yes, I've some research. Not by reading books, because I've read most of them already - Einstein, Hoyle, and even (God forbid!) Mark McCutcheon!

The research has been mainly conducted within my human mind. Without relying primarily on extraneous literary sources. And it leads inexorably to these conclusions:

1. Photons are supposed to be particles of light, which always travel at the speed of light in a perfect vacuum.

2. So, if the Universe was a perfect vacuum, photons would always be perfect plain light-particles, and wouldn't show any colours.

3. Therefore the fact that photons do show colours, ie becoming red or blue, must be due to some influence. What could this influence be? It can't be "distance". Photons don't care about "distance". They go about their business, travelling at the speed of light, whatever "distance" they travel. One photon doesn't change colour just because it's travelled further than another photon. Not in a vacuum.

4. Hence, mere vacuum distance can't be an influence. The change of colour must be caused by the fact that the photons are NOT travelling through a vacuum. They are travelling through interstellar, and intergalactic, hydrogen gas. This gas is ubiquitous throughout the Universe. It's everywhere - it forms a medium through which all photons must pass. Just as for example, all photons in a refracting telescope must pass through the medium of the glass lenses.

5. And the glass lenses slow down the photons, skewing the light-beam, making it go at varying angles. So causing apparent colour changes - the red/blue shifts, which we name "chromatic aberration".

6. If this "chromatic aberration" can be produced by a medium such as glass, I don't see why it can't also be produced by a medium such as hydrogen gas. And produce a chromatic universal "red-shift".

7. In both cases, the effect is only optical. An apparent, perceived effect. It shouldn't necessarily be taken as indicating anything about reality, should it?
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Re: Expansion speeding up

Postby Gfamily2 » Wed Sep 16, 2015 6:26 pm

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Re: Expansion speeding up

Postby david48 » Wed Sep 16, 2015 6:48 pm

Thanks G, I just tried to read the article you very kindly provided, but I got lost when the Lyman-Alpha Forest turned into the Gunn-Peterson Trough. It sounds very weird.

Personally I suspect that no-one really has a clue what's going on!

It's probably best to stick with Newton's Laws, plus Electrons, Protons and Neutrons. All the rest may be only some kind of delirium.
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Re: Expansion speeding up

Postby Gfamily2 » Wed Sep 16, 2015 6:51 pm

david48 wrote:Thanks G, I just tried to read the article you very kindly provided, but I got lost when the Lyman-Alpha Forest turned into the Gunn-Peterson Trough. It sounds very weird.

Personally I suspect that no-one really has a clue what's going on!

It's probably best to stick with Newton's Laws, plus Electrons, Protons and Neutrons. All the rest may be only some kind of delirium.


Yes, if it's beyond you, you're better not pretending you're up to it.
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Re: Expansion speeding up

Postby dave.b » Wed Sep 16, 2015 10:57 pm

LOL!
The Wikipedia article about the Lyman-Alpha Forest is clear enough; hydrogen absorption lines occur at many places in the observed spectrum from the distant source due to red shift. And when the source is so far removed and therefore it's light, as seen here on earth, started out a very long time ago it has so many absorption lines that a good chunk of its spectrum is knocked out, which appears as a trough in a plot of its spectrum.

It is incorrect to think of light as being solely a particle. It is not! Light exhibits both wave like and particle like properties simultaneously. A photon is best thought of as being a pulse of electromagnetic energy arising from the shift of an electron between energy states. Electromagnetic radiation exhibits a field with a frequency and a spin or phase. The frequency places the EMF on a spectrum of frequency of which visible light is just a small part. White light is what we perceive when a spread of visible light emf frequencies are detected by our eyes rather than just a narrow band, which we would see as a particular colour. Polarised light occurs when the spin or phase of the EMFs are in agreement.

Spectral absorption occurs when a photon (being a packet of emf energy) strikes an electron in an atom and is absorbed by it, causing the electron to shift to a new energy level.

Dave B.
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