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Author Topic: Is our Universe static and infinite?  (Read 13204 times)

Offline techmatt

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Is our Universe static and infinite?
« Reply #25 on: 06/05/2009 02:01:38 »
We have equipment that can detect radiation below the visible spectrum. If the universe is ageless as we suspect that it is, much of the radiation will be below the visible spectrum. It will continue to exhibit its spectral structure however. That's how we know that the CMBR is not simply red-shifted starlight. It is black-body radiation. It is all very close to the same frequency.

The problem with the equipment that we currently have to detect the low frequency it the wave length that might be required. The lower the frequency the larger the antenna must be to detect full wave. This is a simple concept that any first year electronics major learns. Maybe the current equipment is not capable of picking up the full wave length and therefore is seems to be the black-body radiation. Ii is really just a case of sensitivity.
 

Offline Vern

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Is our Universe static and infinite?
« Reply #26 on: 06/05/2009 13:08:47 »
We can tune an antenna by adding inductance and capacitance, but to study single sources of energy we need to focus on the source. At the frequencies of the CMBR, we have tuned the receivers to the extent that we can determine the frequency very accurately. It is not possible that the CMBR is red-shifted starlight. It is possible that the CMBR is absorbed and re-emitted starlight. I suspect that the latter is the reality.

It would be interesting to know if the longest wavelength radio sources we observe do contain the fine structure we see in the spectrum of visible starlight. If it does not, we can forget about our speculation that the universe is infinitely old. If it does, it is just one more piece of evidence that the speculation may be real.
 

Offline Bored chemist

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Is our Universe static and infinite?
« Reply #27 on: 06/05/2009 23:08:37 »
It the universe were infinitely hot, where did that infinite energy come from? We suspect that the laws of thermodynamics hold. Overall mass-energy can not increase unless there is some rule that we do not yet know about.
That too is a reason why the universe can't have always been like it is (at least with the laws of physics as we know them). It would have required an infinite energy source.

The evidence is still piling up for Olber and against a perpetual universe, just as I have been saying all along.

Incidentally, there's another aproach to the problem you seem to be looking at. If the visible light has been red shifted so far to long wavelength that it's difficult to measure try looking at, for example, Xrays that have now been shifted to a more convenient region of the spectrum.
Of course, unless you can sort out Olber's paradox you will still be forced to accept that the simple answer to the original question is no.
 

Offline Vern

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Is our Universe static and infinite?
« Reply #28 on: 07/05/2009 21:15:34 »
Quote from: Bored Chemist
Of course, unless you can sort out Olber's paradox you will still be forced to accept that the simple answer to the original question is no.
Olber's paradox has been sorted out.
Quote
I think though that Olbers paradox can be disposed of. The amount of energy per unit of spacial area doesn't increase because the same amount of energy departs as arrives. There is not an infinite amount of energy available.

You assume some sort of creation scheme when you require infinite energy to produce it. I have no problem thinking of an eternal universe that has always been much the same as it is now. Evidence to the contrary requires heavy bending of nature's rules as we know them.

Xray sources shifted into the visible range is interesting. I wonder if we would recognize that if we saw it. They will exist if our eternal scheme is the reality.
« Last Edit: 07/05/2009 21:26:22 by Vern »
 

Offline techmatt

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Is our Universe static and infinite?
« Reply #29 on: 08/05/2009 06:04:55 »
Xray sources shifted into the visible range is interesting. I wonder if we would recognize that if we saw it. They will exist if our eternal scheme is the reality.

Now that is an interesting thought. Would they not appear as stars?
 

Offline Bored chemist

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Is our Universe static and infinite?
« Reply #30 on: 09/05/2009 20:12:13 »
Vern,
Stars burn out. If you don't have a scheme that creates them then they would all be dead by now (in an infinitely old universe).
There are still stars and so either there's something that has been making them, in violation of the law of conservation of energy, or the universe hasn't been around for ever.

As for "Olber's paradox has been sorted out."
Yes, it has; the universe isn't infinitely old so the paradox doesn't apply.
If you postulate an infinite universe then you have to answer Olber's paradox.
Please do so.
 

Offline Vern

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Is our Universe static and infinite?
« Reply #31 on: 10/05/2009 17:19:02 »
Stars convert matter to starlight of many frequencies. When stars burn out, they eventually end up at the centre of a galaxy where they are crunched into energy and spewed out as gamma rays and other forms of energy. The gamma-ray energy and starlight meet up in deep space and congeal into matter again.

Starlight warms space debris and this warmth is seen as the Cosmic Microwave Background Radiation.:)

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If you postulate an infinite universe then you have to answer Olber's paradox.
Please do so.
Quote from: Vern
Olbers Paradox; but it is not so. All of the infinite universe schemes provide a natural disposition for infinite starlight. In the Tired Light scheme, for example, light becomes mass as it is absorbed. It is then re-radiated. We observe this as the Cosmic Microwave Background.
« Last Edit: 10/05/2009 17:25:46 by Vern »
 

Offline Vern

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Is our Universe static and infinite?
« Reply #32 on: 10/05/2009 17:22:15 »
Quote
Now that is an interesting thought. Would they not appear as stars?
I suspect that they would appear as stars; there should be something about their spectrum that would identify them as red-shifted Xray sources.
« Last Edit: 10/05/2009 17:28:00 by Vern »
 

Ethos

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Is our Universe static and infinite?
« Reply #33 on: 09/07/2009 00:52:30 »
If I may be allowed point out; The use of the word "infinity" can and has been used somewhat carelessly within this thread. When we consider an infinity of mass within the infinity of space, one must concede that the volume of space is vastly larger than the mass contained within it. As we consider this great difference in scale, the infinity of mass becomes significantly smaller by comparison. If I remember correctly, the mass density of our universe is very small, only one atom of Hydrogen available in a much larger volume of space. To assume that the infinity of mass-energy will light up an even larger infinity of space is not taking into account the difference between these two values.

 The infinity of mass in an infinite universe is not even close when we consider the volume of space within which it resides! And yes, some infinities are larger than others. Olber is wrong!
« Last Edit: 09/07/2009 00:55:03 by Ethos »
 

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Is our Universe static and infinite?
« Reply #33 on: 09/07/2009 00:52:30 »

 

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