Time Dilation and Quasars

[snowflakeuniverse]

Time Dilation and Quasars

In May of 2001 Hawkins published a paper called “Time Dilation and Quasar Variability”. Part of the Abstract reads as follows.

Hawkins
“We find that the timescale of quasar variation does not increase with redshift as required by time dilation. Possible explanations of this result all conflict with widely held consensus in the scientific community.” http://xxx.lanl.gov/abs/astro-ph/0105073

The conflict arises since this indicates that space-time is not expanding. This is contrary to the evidence of type 1a super novas that confirms the time dilation effect due to the expansion of space.

Initially this topic was posted by Dunash on this BB on January 10, 2002, but there was no follow up discussion of his posting. http://www.badastronomy.com/phpBB/viewtopic.php? I am appreciative for dgruss23 bringing up the paper in the course of a poll discussion called “Is the expansion of space-time accelerating or decelerating?”. http://www.badastronomy.com/phpBB/vi...2&start=50 (Page 3) I believe reference to this paper may also have been found in a discussion about the Red Shift but I could not find it but I think I remember reading it there. Hopefully someone will provide additional links to preserve the reference value of this BB.

I thought that a more through discussion of this topic is in order on its own since it provides evidence that something is wrong with current cosmological models.

I will attempt a “layman’s” description of the report. Hopefully someone with more expertise will provide a more explicit description.

Time dilation.
Time dilation generally refers to an increase in the observed time a physical process occurs. There are at least two possible physical interpretations or descriptions for time dilation. The most common is the application of special relativity. Time progresses comparatively slower for a moving object, so an object observed in the past with a high velocity (indicated by red shift) will have physical processes occur at a slower rate. The decay of a muon entering the earth’s atmosphere is a classic example of how a physical process is slowed when an object is moving at near light speed velocities. The time scale of rapidly moving objects can be described by how long a physical process takes to occur, as predicted by special relativity. Specifically the time scale, Ts, can be described by the red shift proportion z as follows. Ts =Tm/Tl =1+z. Tm = interval of time moving, Tl = time interval of time local or “at rest”, z = ratio of wavelength.

The other physical interpretation is that the expansion of space-time itself results in a time dilation. Lets say that we are at a bowling alley and we roll two balls down the ally separated by 1 second of time. The distance between the two balls remains essentially constant while traveling down the alley. (Ignoring friction effects). The two balls will arrive at the end of the ally one second apart. Now lets throw the two balls again with a 1 second separation, but this time the bowling ally is “stretched” while the balls roll down the alley. This will physically increase the distance between the two balls. For example, Instead of the balls being 2 meters apart, they can end up being 4 meters apart. When the balls reach the end of the alley, in this example, the separation in time for when they reach the end will now be 2 seconds. (Ignoring the effect of the expansion on the velocity and energy of the balls, at least for this posting since the possible variance in the speed of light and the loss of energy of a photon (instead of a bowling ball), with the expansion of space-time is a whole other issue). I prefer this explanation of the cosmological red shift since it keeps galaxies “at rest” locally, allowing them to be carried by the expansion of space-time.

Regardless of the model, the basic general effect of time dilation will be the same. The time dilation will be Td = 1+z. A process that took 1 second to occur in a “rest” frame, will take 2 seconds to occur as measured by an observer if the red shift of the observed object producing the effect has a cosmological red shift of 1.
I am sure some will provide a better explanation of time dilation, and different interpretations, but I hope it gives the reader a general idea.

(In the application of my uniform expansion hypothesis (www.uniformexpansion.com) both special relativity and expansion result in time dilation, but one of the effects is unobservable due to the specific geometric rate the expansion occurs. This would alter the assumed distance of 1asn’s and the assumed “acceleration” (really deceleration) indicated by such. It also addresses the issue involved with no observed time dilation effects noticed in the variation of energy output of quasars. This is merely an aside for now. It is hoped that the postings of others will provide additional explanations and perspectives. )

The time variance of Quasars

The time variance of quasars, while not described in the Hawkins paper, is based upon observed variation in the energy output from quasars. It is the extreme variance of energy output of quasars in short periods of time that has helped determine the size of quasars. Quasars put out about 1,000 times the amount of energy of an entire galaxy, in a region of space 100,000 times smaller. Of course this is based upon the assumption that the cosmological red shift correlates not only to a velocity measure describing the expansion of space but to a distance measure. (v = Ho x D and v causes the red shift). (Some will take issue with this assumption arguing that quasars are much closer, “tired light proponents”).

I regret not being able to find a link with a graph illustrating the time variance of the energy output of quasars. I will try to explain verbally a graph of quasar 3c 279, which is in one of my texts. One of the most dramatic peak cycles of energy output shows that the increase in luminosity varies by a magnitude of 7 over a period of about 1200 days (rise, peak to fall) . There are a number of smaller cycles (rise peak and fall), with a variation of magnitude 2 over about 800 days. Amongst this variation there are additional variations in magnitude of about 1 or perhaps a bit more times over the passage of a just a 50 or so days. There is also some variation with a magnitude of 1 over periods of only a few days. A very “noisy” graph.

While there is great variation in the cycles of energy output from quasars, there is a discernable pattern. Large energy peaks last longer than short energy peaks. Large peaks tend to last a thousand days, etc.

Mathematically, it is possible to extract frequency relationships utilizing a Fourier based transformation with what is called a power spectrum analysis. It allows a statistical manipulation of cyclic processes with a “noise” component. It works best if even numbers of cycles are in the mix, but if there are sufficient numbers of cycles within the analysis, this restraint is not that critical. Categorizing cycle events helps in the statistical evaluation, “large” energy output events last over 1000 days, etc.

The anticipated result

It was anticipated that the further away a quasar was observed, as indicated by the red shift, the greater the time dilation of the cycles observed in the energy output of quasars. The increase in the period of the cycles should correspond to an increasing red shift. Specifically it was anticipated that the cycle length should vary by 1+z. For example, the period of “averaged” cycles should be two times greater than another quasar if the red shift for one quasar has a z of 1 while the other quasar had a z of 3.

No such effect was observed.

This is opposite to the results found with type 1a supernovas. It is assumed that Type 1a supernovas are always the result of a supernova explosion with a white dwarf star with a mass of about 1.44 masses involved. (Baring the variation induced by rotational effects of the two stars involved and the mass of the sister star losing mass to the white dwarf star). (This also assumes that high red shift 1asn’s are the same as “local”, which is an assumption I have issues with). Since the mass involved in the supernova is assumed to be the same, the duration of the event should be generally the same. Time dilation should increase the observed duration of the 1asn by a factor of (1 +z). This time dilation is observed in that the light curves of high red shift supernovas; the “explosion” takes longer to occur the greater the red shift. (Generally).

How can one process associated with Supernovas indicate time dilation associated with red shift, while another process associated with quasars indicate no time dilation associated with red shift?

Snowflake.

[Sam5]

Time dilation should increase the observed duration of the 1asn by a factor of (1 +z). This time dilation is observed in that the light curves of high red shift supernovas; the “explosion” takes longer to occur the greater the red shift. (Generally).

This is caused by a classical Doppler shift that has nothing to do with “relativity”, and it is not “time dilation”. It is caused by an increasing delay in the signals arriving at an observer.

Even the famous moving train whistle will appear to “time dilate” due to the Doppler shift. If the tone of the train whistle lasts for one second at the whistle, then to a stationary observer behind the moving train, it will appear to last slightly longer than 1 second, although it only actually lasts for one second.

The explosion doesn’t “take longer to occur”, it takes longer to observe. The same as with the sound from the moving train whistle.

[dgruss23]

snowflake:
How can one process associated with Supernovas indicate time dilation associated with
red shift, while another process associated with quasars indicate no time dilation
associated with red shift?

One explanation is that the supernova are at cosmological distances and the quasars are local. In fact the observation is what is expected if quasars are local.

Jerry has argued that time dilation has been incorrectly interpreted and has not actually been observed in supernova. If so, then the supernova could also be local or the universe is not expanding.

[Sam5]

Now lets throw the two balls again with a 1 second separation, but this time the bowling ally is “stretched” while the balls roll down the alley. This will physically increase the distance between the two balls. For example, Instead of the balls being 2 meters apart, they can end up being 4 meters apart.

There is another way to do this. Start the balls rolling by means of an explosion behind ball #2. Ball #2 will hit ball #1 and transfer much of its kinetic energy so that ball #1 rolls down the alley at a faster speed than ball #2. Their distance apart increases as both roll down the alley.

In order to “stretch” a bowling alley, you are going to need some form of energy at both ends of the alley. One form has to “hold on” to one end of the alley while the other has to pull on the other end of the alley to make it stretch. Bowling alleys and universes just don’t “stretch” for no reason.

Muons are both accelerating and moving rapidly through the earth’s fields. Their “relative motion” with the earth has nothing to do with their extended lifespan.

[Lunatik]

Snowflake, and all,

Very interesting question, as to why quasar do not seem to register the same time dilation witnessed in gamma ray bursters. If distance is being dilated due to universal expansion, then why not time?

One possible way to approach this is to consider the inverse, conceptually, where the incoming distant cosmic light is now instead outgoing to the highly redshifted regions of deep space. If redshift is due to an expanding universe (and not the result of some still unknown deep space gravity effect, for example), then light outgoing would have to race 'faster' to catch up with the redshifted spatial dimensions at great distances. This, of course, would force us to violate the light constant v = c, since it would now travel at v' = c+z, at least from our point of observation, which is impossible. The way to overcome this impossible situation is to slow down 'time', in effect dilate it, so the light constant is preserved. Of course, if there is no expansion, then the point is moot. But assuming there is, as most astrophysics concludes, then all observations of distant redshifted phenomena should agree, which they do not.

One possibility as to why they do not agree, as pointed out by Hawkins, is that the universe is not expanding. The other possibility is that time is measured differently for different electromagnetic wavelengths. He writes in the above referenced report, http://xxx.lanl.gov/PS_cache/astro-p...05/0105073.pdf 3. Discussions:

"If the timescale of quasar variation were a function of wavelength in the sense that timescales were shorter in the bluer passbands then this might possibly exactly offset the effect of time dilation.

However, he finds this unsatisfactory. Thus, he tends to conclude instead that there is still some unknown physical process to account for why the timescale for quasars gets offset exactly, so time dilation is canceled. The idea that 'time dilation' does not exist, or is modified by red-blue wavelengths begins to undermine Einstein's Special Relativity, since it assumes all light no matter the wavelength to be the same. Also, this last would severely further damage all the great efforts that had gone into understanding the Big Bang theory, and likely kill it.

If the universe were to exhibit distant cosmic redshifting (not from 'tired light', which is disproven) from physical causes we still do not understand, then expansion along with time dilation might have to be revised. Such a possibility would be more realistic if we can find evidence that gravity lensing at cosmic distances is also due to variable-gravity forces, where they are greater in the deep cold of space, for example. Such finding would indeed better explain redshifting cosmic light as it passes through these greater gravity regions. One way to test for this would be to see if there is a gravity lensing effect around (non-luminous) massive bodies in the cold of deep space, such as dust clouds at known distances, though this may be difficult with our existing astronomical instruments. Such measurement, if possible, would reveal whether or not cosmic dust clouds (in cold regions far from star energy) exhibit expected gravity, or greater, than Earth region's Newton's G, and thus if greater coalesce into more mass than the spectral analysis composition of these clouds would predict. If this happened, though it may be difficult to show, then the question as to why time dilation is not equal for all distant phenomena would instead lead to a new interpretation, a new way of seeing why distant light redshifts, and perhaps ultimately lead to a newer understanding of deep space-variable-gravity as well.

So to put a positive spin on this conundrum, instead of time dilation inconsistencies, maybe we are observing a strange gravity effect at cosmic distances instead? Well, I should think deep space greater gravity should be added to the list of possibilities, something to look for.

Ivan

[Russ]

I got five bucks says it's observational error. Since the beginning of astronomy there have been all kinds of "facts" that turned out to be wrong due to observational error. eg: Earth is the center of the universe, the Sun is the center of the universe, there are canals on Mars, Mars/Jupiter/Saturn stop in their paths and go backwards, the universe is static, M31 is a dust cloud, etc., et.al., ad infinitum.

Sooner or later somebody is going to get the right picture and figure it out. =D>

[Cougar]

The problem with this analysis is that, while Ia supernovas are all very similar events and all have roughly the same intrinsic luminosity, quasars are not at all uniform, and particularly pertinent to this discussion, the variations in quasar brightness might be on timescales anywhere from days on up to thousands of days, as in snowflake's example. Since there's no uniformity, it's impossible to tell how much of the variation is due to time dilation and how much is due to the actual variation itself. So how can Hawkins conclude that quasar variations do not exhibit time dilation?

Answer: He uses that old standby that we all know and love, the statistical analysis. He still can't determine how much of any variation is due to time dilation, but he reasons that because of time dilation, the variations of more distant quasars should be longer on average than quasars that are not so distant. But his analysis didn't turn up this expectation.

Well, contrary to Hawkins' claim that "Possible explanations of this result all conflict with widely held consensus in the scientific community," I would contend that there are numerous possible explanations of this result that would not surprise the scientific community in the slightest.

• To start with, statistical analyses typically assume a random sample. Is Hawkins' quasar sample completely random? Perhaps some selection bias crept into this analysis?
  
• As noted above, there are huge differences in quasar variations. If I remember my statistics correctly, if you've got a huge standard deviation, you've got to have a correspondingly large sample size to constrain the size of your sampling error. I've got to figure that Hawkins is up on his statistical methods, but....
  
• What causes quasar variability? I don't think this is very well understood. So who knows, there could actually be some reason that younger (more distant) quasars have shorter variations on average, thus counteracting the lengthening effect of time dilation.

I'm sure there are plenty of other possible explanations. All in all, Hawkins' paper is notable, but the conclusion is fairly weak. Additional confirming evidence is needed.

[Cougar]

If anyone wants a good-sized sample of quasar variabilities, you might want to get ahold of B. C. Wilhite (Chicago), D. E. Vanden Berk (Fermilab), or R. G. Kron (Chicago) who presented The Photometric Variability of 10,000 Quasars in the Sloan Digital Sky Survey at the 199th AAS meeting in Washington, DC, January 2002. As they say, that's almost two orders of magnitude more than any previous quasar variability survey. I'm unsure of the terminology, but if "rest frame time lag" is the same as time dilation, it appears they simply indicated this factor according to the quasar redshift. (?) I tend to think they would have been aware of Hawkins paper written two years earlier, and I find it interesting that they do not mention that the average timescale of quasar variation fails to increase with redshift as required by time dilation.

[dgruss23]

Here is a more recent paper by the same authors that analyzes 25000 quasars.

Cougar:So how can Hawkins conclude that quasar variations do not exhibit time dilation?

Nobody has shown time dilation in quasars.

Cougar: What causes quasar variability? I don't think this is very well understood. So who knows, there could actually be some reason that younger (more distant) quasars have shorter variations on average, thus counteracting the lengthening effect of time dilation.

Hawkins addresses this: It would "require a considerable degree of fiine tuning. In fact the shape of the plots in Fig. 1 would appear to make such fine tuning an unrealistic possibility."

No fine tuning is necessary if the quasars are local. We would not expect to see time dilation in that case.

[d 2022]

No fine tuning is necessary if the quasars are local. We would not expect to see time dilation in that case.

What do you mean by local?Local to the Milky Way?

[dgruss23]

No fine tuning is necessary if the quasars are local. We would not expect to see time dilation in that case.

What do you mean by local?Local to the Milky Way?

No - local meaning within the local supercluster (~20Mpc) but perhaps even out to 100 Mpc which would be local compared to cosmological distances they are normally thought to be at.

[Cougar]

Here is a more recent paper by the same authors that analyzes 25000 quasars.

Which says....

Using a sample of over 25000 spectroscopically confirmed quasars from the Sloan Digital Sky Survey, we show how quasar variability in the rest frame optical/UV regime depends upon rest frame time lag, luminosity, rest wavelength, redshift, the presence of radio and X-ray emission, and the presence of broad absorption line systems. The time dependence of variability (the structure function) is well-fit by a single power law on timescales from days to years. There is an anti-correlation of variability amplitude with rest wavelength, and quasars are systematically bluer when brighter at all redshifts. There is a strong anti-correlation of variability with quasar luminosity. There is also a significant positive correlation of variability amplitude with redshift, indicating evolution of the quasar population or the variability mechanism. We parameterize all of these relationships. Quasars with RASS X-ray detections are significantly more variable (at optical/UV wavelengths) than those without, and radio loud quasars are marginally more variable than their radio weak counterparts. We find no significant difference in the variability of quasars with and without broad absorption line troughs. Models involving multiple discrete events or gravitational microlensing are unlikely by themselves to account for the data. So-called accretion disk instability models are promising, but more quantitative predictions are needed.

So.... ?

Cougar:So how can Hawkins conclude that quasar variations do not exhibit time dilation?

Nobody has shown time dilation in quasars.

There are quite a few correlations in the above abstract. Don't these lead to any conclusions? And by "anti-correlation", do they mean no correlation or inverse correlation?

Cougar: What causes quasar variability? I don't think this is very well understood.

Hawkins addresses this: It would "require a considerable degree of fiine tuning. In fact the shape of the plots in Fig. 1 would appear to make such fine tuning an unrealistic possibility."

Fine tuning. I'm afraid this doesn't say much to me.

[dgruss23]

Cougar: There are quite a few correlations in the above abstract. Don't these lead to any conclusions? And by "anti-correlation", do they mean no correlation or inverse correlation?

They don't lead to any conclusions relevant to Time dilation because that was not studied. But the burden of proof here is on the mainstream to show that these factors can explain why there is no time dilation in quasars.

Time dilation is predicted in the mainstream view and not predicted in the view that quasars are local. So the result supports the local view.

Yes - "anti-correlation" is inverse.

Cougar: Fine tuning. I'm afraid this doesn't say much to me.

Here is the problem. The quasars studied covered a large range of redshift and therefore distance if they are cosmological. Yet the time dilation is not observed. In order to explain the lack of time dilation in quasars, the mechanism responsible must be something that precisely evolves with the quasar population in such a way as to offset the time dilation and exactly cancel it out (observationally). That is fine tuning and is never looked upon favorably. If a scenario was proposed that required fine tuning for an ATM theory, the fine tuning would be taken as a strike against the ATM theory.

In fact fine tuning as an explanation is made extremely improbable from the Hawkins study.

[Jerry]

This is caused by a classical Doppler shift that has nothing to do with “relativity”, and it is not “time dilation”. It is caused by an increasing delay in the signals arriving at an observer.

Cougar has argued the exact opposite (I think it was you, Cougar, sorry if it was someone else), and you are both wrong. It is Doppler, and a very high recessional speeds, it is relativistic Doppler and it does involve relativistic time dilation - how else could you have redshifts greater than one? Without relativity, this would mean exceeding the speed of light.

But the argument is academic, because redshifting is neither Doppler nor relativistic Doppler.

I got five bucks says it's observational error. Since the beginning of astronomy there have been all kinds of "facts" that turned out to be wrong due to observational error. eg: Earth is the center of the universe, the Sun is the center of the universe, there are canals on Mars, Mars/Jupiter/Saturn stop in their paths and go backwards, the universe is static, M31 is a dust cloud, etc., et.al., ad infinitum.

Sooner or later somebody is going to get the right picture and figure it out. =D>

HOW CAN I SPELL NO EVIDENCE OF TIME DILATION :x ?

Let me count to the ways: 1) Rise time of supernova (Wang) 2) Cepheid periods 3) power function of quasars (Hawkins) 4) power function of gamma rays 5) If time dilation is included in the calculation, the magnitudes of SN Ia appear to decrease with distance (Jensen) 6) If the highest magnitude supernova events both locally and at high redshift are Hypernova, the light curves are the same length without correction for time dilation. If this is not correct, then WHERE ARE the high redshift HYPERNOVA? Can anyone show me ANY evidence that time dilation occurs without using a circular argument (that includes time dilation in the data reduction?)

[Cougar]

Time dilation should increase the observed duration of the 1asn by a factor of (1 +z). This time dilation is observed in that the light curves of high red shift supernovas; the “explosion” takes longer to occur the greater the red shift. (Generally).

This is caused by a classical Doppler shift that has nothing to do with “relativity”, and it is not “time dilation”. It is caused by an increasing delay in the signals arriving at an observer.

Cougar has argued the exact opposite (I think it was you, Cougar, sorry if it was someone else), and you are both wrong. It is Doppler, and a very high recessional speeds, it is relativistic Doppler and it does involve relativistic time dilation - how else could you have redshifts greater than one? Without relativity, this would mean exceeding the speed of light.

Doppler? You guys certainly love to take positions that 99% of the astrophysical community have rejected! Doppler effects are caused by motion through space. The distance is increasing between us and these distant bodies, but not because they're moving through space - it's because the space between us and them is expanding. Therefore this is not termed a doppler effect.

[Sam5]

Doppler? You guys certainly love to take positions that 99% of the astrophysical community have rejected! Doppler effects are caused by motion through space. The distance is increasing between us and these distant bodies, but not because they're moving through space - it's because the space between us and them is expanding. Therefore this is not termed a doppler effect.

Distance expands when things move apart through space, thus producing a Doppler effect. Distance contracts when things move toward us, thus producing a blueshift as in the light from M31.

Moving away = Doppler redshift

Moving toward = Doppler blueshift

[Sam5]

how else could you have redshifts greater than one? Without relativity, this would mean exceeding the speed of light.

Right.

[Sam5]

Doppler? You guys certainly love to take positions that 99% of the astrophysical community have rejected!

The astrophysical community told me in books in the 1950s that there were a lot of “green plants” growing all over the surface of Mars.

[Taibak]

Doppler? You guys certainly love to take positions that 99% of the astrophysical community have rejected!

The astrophysical community told me in books in the 1950s that there were a lot of “green plants” growing all over the surface of Mars.

Yes. And heaven forbid astrophysics advancing since then. :roll:

[MrObvious]

Yes. And heaven forbid astrophysics advancing since then.

Had we no probes to go to mars or instruments to probe deeply from earth, we probably still would think there are "green plants" on mars. We know far more about mars now than 50years ago, we know very little more about further galaxies now than we did when we first discovered them by comparision.


Just my opinion but, it seems to me that the whole feild of astrophysics/cosmology is still young. My definition of young is that it's opinion is changing regularly as opposed to how long they have been in service. The other indicator is that many peers do not agree with the conclusions from the same data.

Putting it all together leaves me with the impression that the currently accepted view is just that, not the correct view. I don't have faith in an establishment that maintains it's view is correct until it changes it's view further down the track due to new data. How can anyone????

A better approach would be to NOT claim or imply correctness and not discount theories because they conflict with the currently accepted one....

Other theories should be encouraged, not suppressed. As for arguing that because the general consensus is in favor of one view over another doesn't make it any more likely that it's the correct view. Bias for one theory over another only retards progress in the long run.

Just my 2cents worth.

Regards,

[Cougar]

Distance expands when things move apart through space, thus producing a Doppler effect. Distance contracts when things move toward us, thus producing a blueshift as in the light from M31.

Moving away = Doppler redshift

Moving toward = Doppler blueshift

It's misnamed. It should be cosmological redshift, mainly because when objects DO move through space due to local gravitation (termed peculiar velocity), THAT causes doppler red or blueshifting

[Jerry]

Distance expands when things move apart through space, thus producing a Doppler effect. Distance contracts when things move toward us, thus producing a blueshift as in the light from M31.

Moving away = Doppler redshift

Moving toward = Doppler blueshift

It's misnamed. It should be cosmological redshift, mainly because when objects DO move through space due to local gravitation (termed peculiar velocity), THAT causes doppler red or blueshifting

No its not.
Cougar, you are talking about a conceptual definition of cosmic Doppler shifting: Mathematically it is the same: Hubble certainly observed a doppler shift, the equations used to estimate cosmic light dilution and time dilation are based upon relativistic Doppler motion. Whether you conceptualize this as "expanding space" or differential galactic velocity, the number crunching is the same.

[Sam5]

It's misnamed. It should be cosmological redshift

Doppler did not specify why something moved. He didn’t care if it was because of a steam engine, an explosive force, a pulling force, or whatever. If there is a frequency shift at the observer due to motion, then it is a “Doppler” shift that the observer sees, no matter what the cause of the motion. If you want to call it a “cosmological Doppler shift”, that would be ok.

And it doesn’t matter why things “move”. They can be “carried along” by a conveyor belt, by an SUV, by “expanding space”. It doesn’t matter.

[Cougar]

Actually, you're both wrong. To call a cosmological redshift a "doppler" effect is misleading and wrong. Old astronomy books will certainly talk about "recession velocity," implying that the redshift is a doppler effect, but guys, that paradigm was replaced some time ago.

Also, Special Relativity is not applicable when you're dealing with cosmological distances. General Relativity is. If it's OK to mention the competition's name around here , here's what Sten Odenwald says about it. (His numbers are a little dated, but the framework is still wholly valid.)

None of these factors have anything to do with special relativity, because the reason we have redshifts in the cosmological setting has nothing to do with the speed of the quasar as you might expect if the redshifts were caused by the 'Doppler mechanism'. Cosmological redshifts are not caused by the relative motion between observer and source, but by the difference in the curvature of space between the time the light was emitted by the quasar and observed here some 10 - 20 billion years later.

Using the special relativistic equation for Doppler shifts to convert quasar redshifts into speeds is logically incorrect because the circumstances which make special relativity valid are not obeyed cosmologically. That's why we need Einstein's general relativity theory to guide us.

[Sam5]

Actually, you're both wrong.

That’s impossible. I got my cosmological degree from the College of the Ozarks, and I’m telling you, that was a hard 5-week course.

Doppler wrote about this stuff many years ago, back in the 1840s. He specifically said, “Ven der spacen betwenen der Observern und der Lokomotive Whistlern expandert, dis is der Doppler Effecten.” C. Doppler, “Der Doppler Effecten en Der Expandert Spacen”, Annalen der Physik, 27 Januar, 1842

[snowflakeuniverse]

Hi Cougar

Just a possible model that allows the cosmological red shift to fall under a special relativistic description, submitted for your disapproval.

First imagine a flat land universe that is moving in the “unobserved dimension”.

An observer in flat land can look across his universe and see an object in his universe as it was in the past, since it takes time for the light to be observed

The motion along the unobserved dimension causes a doppler shift, even though the motion is along the unobserved dimension. Light has it’s “foot” in both flatland and the unobserved dimension.

Flatland moves in the unobserved dimension faster in the past than the present,
The faster the flatland universe moves, the greater the Doppler shift. Distant objects are therefore observed with a “Doppler” red shift.

Now imagine instead of a 2 dimensional space moving in an unobserved dimension, imagine 3 dimensional space moving in an unobserved dimension. Imagine three dimensional space moved faster in the past than the present, then the Doppler shift would be greater for objects observed in the past. Just like what we see.

The trick is to have the motion in the unobserved dimension fall within a geometric model that is consistent with our three dimensions of space with two dimensions of time.

Snowflake

[George]

That's pretty interesting, snowflake.

I'm a little green at this so please be tolerant with a couple of questions.

If Flatland's accelerated movement is perpendicular, will there be a redshift?

If the movement is not perpendicular, won't redshifting amounts vary depending on the observation direction?