Relative model of the universe

[michel123456]

 

The CMB has a black body spectrum and therefore an associated temperature. (Or, to put it another way, it is thermal radiation and therefore has a black body spectrum.)

Sorry for the late reply So you say that the temperature of the universe is measured through radiation.

 

And I am pretty sure you could add that the experimental result is matching extremely well theory.

 

from http://www.damtp.cam.ac.uk/research/gr/public/cmbr_temp.html

 

IOW you are saying that the temperature predicted by Relativity matches exactly the measured one.

 

Doesn't that mean that the temperature is relative?

Edited February 11, 2016 by michel123456

[Strange]

Doesn't that mean that the temperature is relative?

 

Relative to what?

 

But, yes. Temperature is observer dependent. Which is why observers in the past would have seen a higher temperature (and therefore a younger universe) and observers in the future will see a lower temperature (and therefore an older universe).

[michel123456]

 

Relative to what?

 

But, yes. Temperature is observer dependent. Which is why observers in the past would have seen a higher temperature (and therefore a younger universe) and observers in the future will see a lower temperature (and therefore an older universe).

That was not what I meant by relative.

I meant relative to the observer in the sense that every observer would measure the same temperatures (the same radiations) no matter his position in the universe and no matter his time frame.

Your explanation is that of an absolute universe where each time frame is linked to a specific temperature. My concept is that of a relative universe where each observer will measure the same thing.

[Strange]

 

My concept is that of a relative universe where each observer will measure the same thing.

 

Which is contradicted by both theory and evidence.

 

So I have suggest that this be moved to Speculations. Do you have anything other than assertions to support your concept?

Edited February 13, 2016 by Strange

[swansont]

That was not what I meant by relative.

 

 

That's what everyone else means by relative.

[michel123456]

 

Which is contradicted by both theory and evidence.

 

So I have suggest that this be moved to Speculations. Do you have anything other than assertions to support your concept?

Isn't theory about relativity?

Doesn't evidence confirm relativity?

Edited February 13, 2016 by michel123456

[Strange]

Isn't theory about relativity?

Doesn't evidence confirm relativity?

 

There is 100 years of evidence confirming general relativity. And about 90 years of evidence supporting the big bang model (based on GR).

 

You seem to be contradicting this on the basis that "you think that is how it is" with no evidence or theory to support you.

[Mordred]

That was not what I meant by relative.

I meant relative to the observer in the sense that every observer would measure the same temperatures (the same radiations) no matter his position in the universe and no matter his time frame.

Your explanation is that of an absolute universe where each time frame is linked to a specific temperature. My concept is that of a relative universe where each observer will measure the same thing.

This isn't what would happen. At least not without having the same reference frame.

 

Take a moving observer he wouldn't see a uniform homogeneous and isotropic universe. Not unless he accounts for his own motion.

 

One key aspect you should familiarize yourself with is the term "fundamental observer" which is the proper time measured by an observer at rest with respect to the local matter distribution.

 

Measurement of temperature, energy, mass etc are all relative to the observer. Unless corrections for the relativistic effects are accounted for different observers will not come to the same conclusions.

 

The first conclusion that is needed is a homogeneous and isotropic mass distribution. Luckily for us we have this wonderful CMB as confirmation.

 

Makes a great reference point. Once we know the universe is homogeneous and isotropic we can conclude that the thermodynamic properties must also be homogeneous and isotropic.

 

With temperature varying by way of volume.. we can now use temperature as a time clock reference. ( of course studying each particle to learn it's equations of state goes a long way into determining what the temperature should be)

Edited February 13, 2016 by Mordred

[michel123456]

This isn't what would happen. At least not without having the same reference frame.

 

Take a moving observer he wouldn't see a uniform homogeneous and isotropic universe. Not unless he accounts for his own motion.

 

One key aspect you should familiarize yourself with is the term "fundamental observer" which is the proper time measured by an observer at rest with respect to the local matter distribution.

 

Measurement of temperature, energy, mass etc are all relative to the observer. Unless corrections for the relativistic effects are accounted for different observers will not come to the same conclusions.

 

The first conclusion that is needed is a homogeneous and isotropic mass distribution. Luckily for us we have this wonderful CMB as confirmation.

 

Makes a great reference point. Once we know the universe is homogeneous and isotropic we can conclude that the thermodynamic properties must also be homogeneous and isotropic.

 

With temperature varying by way of volume.. we can now use temperature as a time clock reference. ( of course studying each particle to learn it's equations of state goes a long way into determining what the temperature should be)

Talking about the "varying temperature by way of volume", how do we know for sure that the measurement would be different for another observer in the universe? I mean, this other random observer would also observe the constancy of C and use a same theory of relativity. What thing would he measure differently from us?

---------------

For example, this other random observer would measure another value for the CMB that does not relate exactly to a black body radiation?

[Mordred]

Well if the observer understands relativity and he's in a gravity well. Then most likely he will adjust the redshift data correction to his environment. Now assuming he's using the same metrics as us he will establish a Cosmic time.

 

https://en.m.wikipedia.org/wiki/Cosmic_time

 

Redshift is also temperature related via Wein's displacement law.

 

https://en.m.wikipedia.org/wiki/Wien%27s_displacement_law

 

As far as a moving observer let's look at our own planet and data. Earth moves, so does our solar system and galaxy. This causes an anisotropy dipole in temperature measurements.

 

"CMBR dipole anisotropy Edit

From the CMB data it is seen that the Local Group (the galaxy group that includes the Milky Way galaxy) appears to be moving at 627±22 km/s relative to the reference frame of the CMB (also called the CMB rest frame, or the frame of reference in which there is no motion through the CMB) in the direction of galactic longitude l = 276°±3°, b = 30°±3°."

 

Note we established the CMB as a reference frame...Rather convenient as it's as close to a perfect blackbody as your likely to get.

 

https://en.m.wikipedia.org/wiki/Cosmic_microwave_background.

 

you can see that we must always account for observer influence. This is an integral aspect in any cosmological measurement.

 

 

Now let's step back to the observer in the gravity well. First off in research lets assume he's studied spectography of various elements in particular hydrogen.

 

https://en.m.wikipedia.org/wiki/Emission_spectrum

 

Which he lab tests. When he looks out and measures hydrogen in the universe he will notice that redshift is altering his data. So he can then apply the correction and determine the gravitational redshift influence

Edited February 13, 2016 by Mordred

[Strange]

Talking about the "varying temperature by way of volume", how do we know for sure that the measurement would be different for another observer in the universe?

 

We have a very well tested theory supported by masses of evidence.

 

What evidence do you have that they would not measure what we expect?

[michel123456]

 

We have a very well tested theory supported by masses of evidence.

 

What evidence do you have that they would not measure what we expect?

I know a scientist somewhere on BX442 galaxy but my question to him is still on the road.

Who do you know? Do you have (a single) evidence that any other random observer will observe something different than what we observe?

Well if the observer understands relativity and he's in a gravity well. Then most likely he will adjust the redshift data correction to his environment. Now assuming he's using the same metrics as us he will establish a Cosmic time.

 

https://en.m.wikipedia.org/wiki/Cosmic_time

 

Redshift is also temperature related via Wein's displacement law.

 

https://en.m.wikipedia.org/wiki/Wien%27s_displacement_law

 

As far as a moving observer let's look at our own planet and data. Earth moves, so does our solar system and galaxy. This causes an anisotropy dipole in temperature measurements.

 

"CMBR dipole anisotropy Edit

From the CMB data it is seen that the Local Group (the galaxy group that includes the Milky Way galaxy) appears to be moving at 627±22 km/s relative to the reference frame of the CMB (also called the CMB rest frame, or the frame of reference in which there is no motion through the CMB) in the direction of galactic longitude l = 276°±3°, b = 30°±3°."

 

Note we established the CMB as a reference frame...Rather convenient as it's as close to a perfect blackbody as your likely to get.

 

https://en.m.wikipedia.org/wiki/Cosmic_microwave_background.

 

you can see that we must always account for observer influence. This is an integral aspect in any cosmological measurement.

 

 

Now let's step back to the observer in the gravity well. First off in research lets assume he's studied spectography of various elements in particular hydrogen.

 

https://en.m.wikipedia.org/wiki/Emission_spectrum

 

Which he lab tests. When he looks out and measures hydrogen in the universe he will notice that redshift is altering his data. So he can then apply the correction and determine the gravitational redshift influence

So you say another observer would collect a different data than what we do?

A different redshift for example?

[Strange]

I know a scientist somewhere on BX442 galaxy but my question to him is still on the road.

 

That's a no, then.

 

 

Who do you know? Do you have (a single) evidence that any other random observer will observe something different than what we observe?

 

We have a very well supported theory. You have nothing. I'll stick with the science, thanks.

 

So far you have given no reason for your view other than you think it should be that way. All the evidence is that the universe is expanding and cooling. You have shown nothing to contradict this.

[Mordred]

So you say another observer would collect a different data than what we do?

A different redshift for example?

Definetely you have several types of redshift. Gravitational, Doppler and Cosmological. However these can be corrected

[michel123456]

 

That's a no, then.

 

 

We have a very well supported theory. You have nothing. I'll stick with the science, thanks.

 

So far you have given no reason for your view other than you think it should be that way. All the evidence is that the universe is expanding and cooling. You have shown nothing to contradict this.

The idea comes from this:

You are observer A here on Earth observing B getting away at near C velocity. Following Relativity: you are observing B being time dilated and length contracted and you observe B getting more and more massive.

However B observes nothing unusual in his own situation. Reversely he observes A getting time dilated length contracted and A getting more and more massive. And A observes nothing unusual in his own situation.

That is what relativity says. Observer A observes the same thing with observer B.

 

However, that is not what one should expect: simple logic would be to say that indeed observer gets more massive and thus looking back B observes A getting less and less massive. This last is wrong. The correct is that A and B observe the same effects.

 

In our case, the result of data combined with relativity is the BB theory. That is what A observes.

But does that mean that an object B that is 13 billion years from us must obligatory observes a universe denser and hotter?

Because the hotter and denser universe is what WE observe.

Doesn't the logic of relativity say that both observers A and B are observing the same thing?

[Strange]

The idea comes from this:

You are observer A here on Earth observing B getting away at near C velocity. Following Relativity: you are observing B being time dilated and length contracted and you observe B getting more and more massive.

However B observes nothing unusual in his own situation. Reversely he observes A getting time dilated length contracted and A getting more and more massive. And A observes nothing unusual in his own situation.

That is what relativity says. Observer A observes the same thing with observer B.

 

However, that is not what one should expect: simple logic would be to say that indeed observer gets more massive and thus looking back B observes A getting less and less massive. This last is wrong. The correct is that A and B observe the same effects.

 

In our case, the result of data combined with relativity is the BB theory. That is what A observes.

But does that mean that an object B that is 13 billion years from us must obligatory observes a universe denser and hotter?

Because the hotter and denser universe is what WE observe.

Doesn't the logic of relativity say that both observers A and B are observing the same thing?

 

OK. But this is completely different from what (I thought) you were saying. Yes, two observers at the current time will observe the same thing (taking into account any differences in motion relative to the CMB).

 

But that is not the same thing as an observer today and an observer sometime in the future. They will not observe the same thing. Someone in a billion years will see a universe that is a billion years older and cooler.

[TakenItSeriously]

I think the OP is referring to what the conclusions about that rate of expansion of the universe is increasing and therefore requires dark energy is based upon which isn't GR, though it claims to follow GR.

 

The way that the rate of expansion of the universe has been defined seems to rely on the notion that change can only be measured across states of fixed time which GR denies.

 

Therefore the "states" of the universe were redefined to fit this notion. They use hypothetical states of the universe which are defined to follow a fixed timeframe in an attempt to get around GR. For example, GR requires states of existence that involve a time regression of 1year/light year of distance from the observer.

 

I would agree that this doesn't follow GR and the notion that fixed time is a requirement for measuring change is a false axiom that was created based upon how we typically think of change occurring.

Edited February 15, 2016 by TakenItSeriously

[Strange]

I think the OP is referring to what the conclusions about that rate of expansion of the universe is increasing and therefore requires dark energy is based upon which isn't GR, though it claims to follow GR.

 

As the OP hasn't mentioned dark energy or accelerating expansion, this seems to be your own problem, not his. You probably should have started your own thread, rather than hijacking this one. Dark energy is part of GR (it can be represented by the "cosmological constant" which was initially introduced by Einstein).

 

The way that the rate of expansion of the universe has been defined seems to rely on the notion that change can only be measured across states of fixed time which GR denies.

 

The rate of expansion is a scale factor derived from the Einstein Field Equations.

https://en.wikipedia.org/wiki/Friedmann%E2%80%93Lema%C3%AEtre%E2%80%93Robertson%E2%80%93Walker_metric

 

For example, GR requires states of existence that involve a time regression of 1year/light year of distance from the observer.

 

The fact that light takes 1 year to travel a light year comes from the definition of "light year", so I'm really not sure what your point is.

[TakenItSeriously]

As the OP hasn't mentioned dark energy or accelerating expansion, this seems to be your own problem, not his. You probably should have started your own thread, rather than hijacking this one. Dark energy is part of GR (it can be represented by the "cosmological constant" which was initially introduced by Einstein).

He referred to expansion which is the same model that accelerated expansion and therefore dark energy was extrapolated from later.

 

This model defines its own hypothetical states of measuring time and distance which may be extrapolated from GRs field equations but do not follow the laws of GR. For example, using these definitions of time and distance, the speed of light is not a constant and you can have relative motion that exceed the speed of light due to expansion.

 

In this model measuring distance is done following a line where time is held constant or its equivalent in a homogeneous isotropic universe where density is a constant.

 

To clarify my point about time regression, this model uses measurements that take time regression out of the equation.

 

Your right in that this may not be the point he was trying to make which is why I worded my post the way I did. Your also right in that I do have a problem with how expansion handles its model which I think I made clear. However, I can assure you it wasn't done as an attempt to hijack this thread.