Red shift and the expanding universe

espritch

Graduate Poster
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I've been thinking about the big bang and I've come up with a hypothesis (or perhaps a I should call it a speculation) to tie together some anomalies and explain how it all works. I'll call it the Zero Point Conversion hypothesis. First, let's take a look at some generally accepted aspects of the universe.

1. The universe is expanding. According to the inflationary big bang model, around 13 billion years ago, the current observable universe occupied a very tiny volume of space at a very high temperature. There was a brief period of extremely rapid expansion (called hyperinflation) after which the rate of expansion slowed greatly. As the universe expanded, it cooled and energy coalesced into matter which eventually formed the stars and planets of our current universe.

2. Observations of type Ia supernovas indicate that the rate of expansion of the universe is accelerating. This has lead physicists to postulate the existence of an unknown force called dark energy which drives this expansion (anomaly #1).

3. Space is not "nothing", or at least it isn't empty. It contains zero point energy. This energy is predicted by Quantum Theory. It results in the production of virtual particle pairs that constantly created and annihilated in the vacuum. These virtual particles are in turn responsible for some observable effects such as the Casmire effect.

4. An effect of the expansion of space is the red shift seen in the light from most objects in the universe. As space expands, the wavelength of light is stretched. A longer wavelength means a shift toward the red end of the spectrum. It also means less energy. Longer wavelength electromagnetic waves have less energy than short wave length electromagnetic waves. This is anomaly #2. According to the law of conservation of matter and energy, matter and energy are never created or destroyed. The form of matter or energy can change and matter can be converted to energy and energy to matter, but the sum total of matter and energy should remain the same. The cosmological red shift, however, seems to defy this law. Photons everywhere in the universe are losing energy due to red shift.

5. There are four recognized forces in nature: electromagnetic energy, the nuclear strong force, the nuclear weak force, and gravity. According to physicists, electromagnetic energy, the strong force, and the weak force are all related and, in the extremely hot environment at the start of the big bang, they were in fact indistinguishable.

So far this is all generally well know and accepted physics. But now I'm going to make some assumptions.

Assumption 1: The amount of zero point energy in a given volume of space is fixed. I am under the impression that quantum theory predicts a specific value for the amount of zero point energy in a given volume of space. I could be mistaken in which case this hypothesis could run head long into a brick wall in my very first assumption. If this assumption is correct, the expansion of space requires an increase in the amount of zero point energy. Or to put it another way, an increase in zero point energy results in expansion of space.

Assumption 2: The law of conservation of matter and energy is in fact a law and applies even in an expanding universe. The red shift represents not a loss of energy but a conversion of energy to a different form - namely zero point energy.

Assumption 3: Although red shift in responsible for most conversion of energy into zero point energy, this conversion can occur without red shift, although at a very limited rate. This assumption is necessary mainly to get the ball rolling.

Using these assumptions, let's turn back the clock some 13 billion years. All the universe exists as a vast amount of undifferentiated energy in a minuscule amount of space with very little zero point energy. A tiny amount of this energy is converted to zero point energy and space begins to expand. As soon as the expansion begins, all the energy in the universe is subject to red shifting and the amount of zero point energy begins to increase rapidly leading to hyperinflation. As the universe expands it cools and at a critical point, the electromagnetic, strong, and weak forces differentiate and much of the energy in the universe changes into matter. Matter is not subject red shifting so the supply of new zero point is greatly reduced. With much less new zero point energy available, hyperinflation ends. There is still some electromagnetic energy out there in the form of the Cosmic Microwave Background radiation and it continues to supply zero point energy for expansion but at a much slower rate. If that was the end of the story, the expansion would grow slower and slower as the CMB became cooler and cooler. But, of course, that isn't the end of the story because there is a fourth force in nature.

Over time, gravity began to exert itself on the newly formed matter, coalescing it into stars. When these began to light up, electromagnetic energy was liberated from matter and flowed into the gradually expanding universe. This released energy is converted by red shift into more zero point energy which produces more expansion which produces more red shifting which accelerates the conversion and expansion.

Using our assumptions, we have provided an explanation for why hyperinflation started and why it stopped. We've also provided an explanation for why the expansion of the universe is currently accelerating, all without requiring an unknown dark energy. We've also linked a large scale phenomenon of the universe (expansion) with an aspect of quantum theory (zero point energy). All of which makes this an attractive notion. Of course an attractive notion isn't necessarily a correct one, but it's at least worth thinking about.

I'm sure by now you are all chomping at the bit to point out to me just precisely where I have gone horribly wrong in my thinking. So have it. ;)
 
Your suggestion doesn't make sense because the zero point energy depends upon the field(s) you're talking about, not the mass-energy of the field excitations. Remember that particles in Quantum Field Theory are identified as excitations of the relevant field.

When you talk about 'energy' you need to be specific - electromagnetic energy (i.e. photons) or what? It's true that we don't know where the energy associated with dark energy comes from (if it exists), and the vacuum energy could well be the source of this. However, talking about energy being transferred to and from the zero point energy simply doesn't make sense. Unfortunately, this is all wrapped up in renormalization and discussion of the zero point can be tricky at best. Sorry :boggled:
 
4. An effect of the expansion of space is the red shift seen in the light from most objects in the universe. As space expands, the wavelength of light is stretched. A longer wavelength means a shift toward the red end of the spectrum. It also means less energy. Longer wavelength electromagnetic waves have less energy than short wave length electromagnetic waves. This is anomaly #2. According to the law of conservation of matter and energy, matter and energy are never created or destroyed. The form of matter or energy can change and matter can be converted to energy and energy to matter, but the sum total of matter and energy should remain the same. The cosmological red shift, however, seems to defy this law. Photons everywhere in the universe are losing energy due to red shift.

In a vaccume with no gravity:
If I walk away from you while squirting you with a hose (squirting at constant rate while walking away faster & faster), the pressure gets weaker and weaker. Untill the point where I am walking faster than the speed of the hose, in which point you wont get wet at all.

I gather thats whats happening to the energy during a red-shift.
 
In a vaccume with no gravity:
If I walk away from you while squirting you with a hose (squirting at constant rate while walking away faster & faster), the pressure gets weaker and weaker. Untill the point where I am walking faster than the speed of the hose, in which point you wont get wet at all.

I gather thats whats happening to the energy during a red-shift.
Nica analogy - that's pretty good.

If the hose squirts at speed v, then the energy per unit mass is v^2/2 ... but if you move away from your target at speed u, then the target only gets (v-u)^2/2 per unit mass arriving.

Expanding space does not expand the wavelength of the photons. They stay the same. The exanding space moves objects apart. Moving apart produces the cosmological doppler (red) shift, since the source is moving away from the observer.

Usually, we would think of this as meaning that the speed of the approaching photons is less ... but, since speed of light is constant, it actually means that the energy and momentum of the photons is decreased.

I think this was a good choice to illustrate the fundamental misunderstandings in the speculation. It was a nice try though.

I remember having a similar speculation that the missing mass is stored as some ind of binding energy ... perhaps it's gravitons? <shakes head sadly>
 
"Expanding space does not expand the wavelength of the photons. They stay the same. The exanding space moves objects apart. Moving apart produces the cosmological doppler (red) shift, since the source is moving away from the observer."

I dont understand your reply. You are saying that no change of characteristics of the light photons occur? If that were true, we wouldnt be able to measure a doppler-type effect.
I understand its nothing to do with expanding space & only seperating objects. But I don't get what you're trying to say there. And I still think my origional statement is valid.
 
Usually, we would think of this as meaning that the speed of the approaching photons is less ... but, since speed of light is constant, it actually means that the energy and momentum of the photons is decreased.

How can this be so? I would have thought that if the speed of light is constant, then the energy and momentum of the photons would also be constant. Are you saying that the speed of light is constant but somehow the speed of photons is not? In other words, how is something that is not effected by motion, effected by motion?

Thanks also for your "A Crash Course in Relativity" Thread. Unfortunately it didn't help things much for me. In the small amount of spare time I have available, I'm trying to learn more about the subject from the wonderful resources on the internet. When I am more "up to speed" I guess I will either understand or be able to debate with more knowledge.
 
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How can this be so? I would have thought that if the speed of light is constant, then the energy and momentum of the photons would also be constant. Are you saying that the speed of light is constant but somehow the speed of photons is not? In other words, how is something that is not effected by motion, effected by motion?
The energy carried by the photon is proportional to the frequency. The frequency is affected by the motion, so the energy is. Imagine you are moving away form the light source. The time you will measure between two valleys in the wave (the frequency) will be lower than that if you were static wrt the source. But the wave itself is still propagating at the SOL.
 
The energy carried by the photon is proportional to the frequency. The frequency is affected by the motion, so the energy is. Imagine you are moving away form the light source. The time you will measure between two valleys in the wave (the frequency) will be lower than that if you were static wrt the source. But the wave itself is still propagating at the SOL.

Thanks for a very concise answer.
 
And by the way, the time was supposed to be higher thus making the frequency, and the energy, lower.
 
And by the way, the time was supposed to be higher thus making the frequency, and the energy, lower.

I’m not sure if it is appropriate to use sound as a comparison to light, but is this a reasonable analogy to what is happening with the motion of light?

If a person was talking on a loud hailer from a vehicle that was travelling toward me at speed, I would hear the words at the correct speed (not faster than normal) but they would be at a higher pitch (frequency) than normal. When the vehicle passes me I would then hear the words at a lower pitch but not slower than normal. In other words, the speed that I here the words at is not changed by the relative motion but the pitch is.
 
I’m not sure if it is appropriate to use sound as a comparison to light, but is this a reasonable analogy to what is happening with the motion of light?

If a person was talking on a loud hailer from a vehicle that was travelling toward me at speed, I would hear the words at the correct speed (not faster than normal) but they would be at a higher pitch (frequency) than normal. When the vehicle passes me I would then hear the words at a lower pitch but not slower than normal. In other words, the speed that I here the words at is not changed by the relative motion but the pitch is.

Yes, in fact they do refer to redshift as being Doppler effect.
 
Davoman said:
"Expanding space does not expand the wavelength of the photons. They stay the same. The exanding space moves objects apart. Moving apart produces the cosmological doppler (red) shift, since the source is moving away from the observer." (I said.)

I dont understand your reply. You are saying that no change of characteristics of the light photons occur? If that were true, we wouldnt be able to measure a doppler-type effect.

I understand its nothing to do with expanding space & only seperating objects. But I don't get what you're trying to say there. And I still think my origional statement is valid.

Well, I was responding to the following from espritch, quoted (by you) in your post:
espritch said:
As space expands, the wavelength of light is stretched.

In responce to your post, I said:
Simon said:
Nica analogy - that's pretty good.

If the hose squirts at speed v, then the energy per unit mass is v^2/2 ... but if you move away from your target at speed u, then the target only gets (v-u)^2/2 per unit mass arriving.
... the rest of the passage was continuing the theme of expanding on your point. So, yes, your original statement is still valid. I was attemting to reinforce it.

Enjoy.
 

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