Expanding Universe: Is everything really getting bigger?

[turbo]

Or, for that matter, any theory that predicts the time dilation of light curves of distant supernovae.

I have a question regarding time-dilation. As we search for supernovae at extreme distances (near the limits of detectability), aren't we selecting for the brightest (largest) events, and aren't they going to have broader luminosity curves, mimicing time-dilation?

If supernova light curves are broadened by time-dilation/cosmological expansion, then we should expect to see the effects of time dilation in the luminosity curves of quasars, and the effect should grow with redshift. M.R.S. Hawkins studied a selection of over 400 quasars that have been monitored regularly for 24 years and found no evidence of time-dilation in their light curves.

http://arxiv.org/PS_cache/astro-ph/pdf/0105/0105073.pdf

 

[turbo]

My model of ZPE/light interaction is probably not what most people think about when they talk about "tired light" theories, so I may not be accurately addressing your objections, but let me give it a shot...

My understanding is that a reduction of energy in this way should result in a change of momentum as well, which should in turn lead to a loss in resolution (increased blurring) of distant objects, which is not seen in practice?

If you send a beam of light through a glass window, the light may be refracted (bent), depending on the shape and orientation of the surfaces of the window, but it is not significantly diffused (blurred). This despite the fact that the light propagates through the glass at significantly slower than the theoretical speed of light in a vacuum. Why should light's interaction with the EM field of the vacuum cause blurring?

Also I believe it has been shown the tired light model cannot produce a blackbody spectrum for the Cosmic Microwave Background without some incredible coincidences.

Can you supply a citation? If the signature energy of the ZPE fields is 2.73 degrees K and the virtual pairs of the ZPE arise in a broad spectrum of energies, how can you exclude the possibility that its radiation signature is a perfect black-body spectrum?

In addition there is something called the Tolman surface brightness test that tired light also fails?

MF

The Tolman test is interesting, but given the observance of non-cosmological redshifts, it is difficult to see how it can be accurately performed, since you must be able to estimate radial distances to determine the extinction formulae. This is not a trivial problem.

For instance, did you know that the eleven companion galaxies of M81 are all redshifted with respect to their host? Every single one. Since they are circling M81, some should be approaching us (blueshifted) some should be moving roughly perpendicular to our line of sight (same redshift as M81) and some should be receding from us (redshift). This is not the case, though, so their excess redshifts must be due to something other than their proper motion. The chance of a single companion being redshifted due to proper motion is less than 1/2 due to orientation of orbital planes and the chance that their current motion might be perpendicular line of sight, but let's use 1:2 and be very generous to the Standard Model. The probablility that we will observe all 11 companions moving away from us AT THE SAME TIME is 1:2048. That is a very strong indication that these companions have an intrinsic redshift relative to their massive host. Due to orbital inclinations, etc, a closer approximation might be 1:3, but that puts the chances of that all 11 companions are moving away from us at a forbidding 1:177,147.

Again, galaxy morphology has an effect on redshift, and thus will contaminate luminosity relationships.

http://arxiv.org/ftp/astro-ph/papers/0310/0310284.pdf

Also, when you are observing distant galaxies to determine their luminosities, you are observing them as they existed billions of years ago, when they were much younger. The Standard Model demands heirarchical galaxy formation, and if that is true, nearby galaxies have had billions of years of additional galactic evolution than the very distant (young) ones. How do you correct for that? Again, not a trivial problem, so Lubin and Sandage may not be the final word on the Tolman effect.

I don't think we have all the answers yet. In many instances we're probably not even asking ourselves the right questions yet.

 

[misskitty]

Thank you Self Adjoint. How do you tolerate my insecent questioning? Thanks.

I think Turbo-1 raises an excellent point. Usually humans spend a long time asking the wrong questions, but how can we find the right questions to ask unless we ask the wrong ones and realize we were wrong. We can't. That's why its called learning.

What does the Tolman test do? What does it look for?

 

[turbo]

I think Turbo-1 raises an excellent point. Usually humans spend a long time asking the wrong questions, but how can we find the right questions to ask unless we ask the wrong ones and realize we were wrong. We can't. That's why its called learning.

What does the Tolman test do? What does it look for?

Hi Misskitty! I'm in New England too, although Maine is at the northern (coldest) extent of that association, and the eastern extent (days begin and end earlier!) as well. Man, it's dark here at quitting time!

We often are crippled by the inability to ask the right questions, and the pressures can be political, professional, or otherwise. Right now, there is a huge pressure against raising concerns about whether redshifts are entirely due to cosmological expansion (with small contributions from proper motion), or whether some redshifts might be intrinsic. If you pursue the concept that some objects (quasars, Seyfert galaxies, etc) might have an intrinsic excess redshift, you will be labelled a "crank" by the establishment and you will be ignored, marginalized, or attacked.

The Tolman test is the the examination of the extinction of luminosity relative to distance. The question is whether the drop in luminosity is the result of simple distance, or if it is the result of the metrics of an expanding universe.

Please keep asking questions, and please keep questioning the people who answer you if the answers dodge the REAL issues.

 

[Skomatth]

Can someone remind me what is causing the redshift? Commonly cited is the "expansion of space" but is this due to the big bang which inflationary cosmology says was caused by negative pressure of the inflaton field? Has this field reached a zero value now or is it still responsible for the expansion we see? I've also read dark energy which makes up about 70% of the universe's density is responsible. Can someone clear this up for me?
Please distinguish between how standard big bang theory and the inflationary version of it answer these questions.

 

[moving finger]

Can someone remind me what is causing the redshift? Commonly cited is the "expansion of space" but is this due to the big bang which inflationary cosmology says was caused by negative pressure of the inflaton field? Has this field reached a zero value now or is it still responsible for the expansion we see? I've also read dark energy which makes up about 70% of the universe's density is responsible. Can someone clear this up for me?
Please distinguish between how standard big bang theory and the inflationary version of it answer these questions.

wow - I can see fireworks coming now - we've already seen there are widely differing opinions on all this!

 

[chronon]

Remember Newton's 1st law. You don't need anything to keep the expansion of the universe going. If it was expanding in the past then it will keep on expanding. For a cosmological constant of zero if a system becomes bound together then it will stay bound together - there's nothing pushing it to take part in the expansion.

In the case of a positive cosmological constant, the expansion of the universe is accelerating, and there will be a small effect on bound systems, However, if it is a cosmological constant, then this won't cause bound systems to join in with the expansion, it will just mean that orbits are larger by a tiny amount than they otherwise would be.

 

[turbo]

Can someone remind me what is causing the redshift? Commonly cited is the "expansion of space" but is this due to the big bang which inflationary cosmology says was caused by negative pressure of the inflaton field? Has this field reached a zero value now or is it still responsible for the expansion we see? I've also read dark energy which makes up about 70% of the universe's density is responsible. Can someone clear this up for me?
Please distinguish between how standard big bang theory and the inflationary version of it answer these questions.

What causes redshift? There are a lot of ways to look at cosmological (distance-related) redshift. Simplistically, one could equate it to a speed of recession (Doppler-like) effect in an expanding universe. That's probably not going to work real well. You might also equate it to the time that light requires to pass through present units of space-time compared to the size of the units of space-time when the light was emitted, also assuming an expanding universe.

You may wish to model redshift as a gradual loss of energy of EM waves as they traverse the EM fields of the quantum vacuum that suffuse "empty space" in a non-expaning universe. This is my preference. Halton Arp, whom I respect for his work with intrinsic redshifts, has a personal distate for this model, but I believe that it is correct and that it will ultimately allow for the reconciliation of quantum field theory with GR.

Non-cosmological redshift can be caused by the interaction of EM with strong gravitational/EM fields. Decades ago, we measured the gravitational redshift of Sirius' companion. Some people seem to ignore this result today or perhaps have forgotten the importance of it back then. Today (although this interpretation is widely ignored) we are currently measuring the gravitational redshifts of the accretion zones of black holes. These are the measured redshifts of quasars. Quasars (in the Arp/Burbidges/et al model) are gravitationally-ejected black holes that evolve, and eventually permit the formation of stars, nebulae, etc, making a new galaxy. There is an apparent evolution of quasars to AGNs and to more mature galaxies. The younger the guasars are and the smaller their accretion zones, the fainter and the more red-shifted they will appear to us. Sound familiar?

Before you reject this concept out of hand, please realize that the most highly redshifted quasars yet discovered (z~6.5) exhibit super-solar metallicities, suggesting that they formed out of materials at least as old as our galactic neighborhood - although our Milky Way is over 13Gy removed from that era. I too believe that quasars are ejected black holes, but that the redshift of a quasar is not a function of its age (how can a quasar know how old it is?), but that the redshift is instead a function of the density of its accretion zone. The thinner the accretion zone, the closer to the event horizon, the dimmer the luminosity and the more redshifted the EM will be.

About the popular conception of quasars: Please consider that if we accept that redshift is equal to distance, these z~6.5 monsters have to have central black hole masses equal to at least several billion Sols and reside in galaxies of approximately a trillion Sols. If quasar redshifts are intrinsic (at least in part), quasars do not have to be such monsters, and their metallicities are no longer a problem. They do not have to be hyper-luminous, yet compact enough to fit within Earth's orbit. The really big problems go away.

Is it possible that our understanding of redshift is incomplete? What do you think? When the Webb telescope and the Large Binocular Telescope come on line, and some eager post-grad measures the spectrum of an even more highly redshifted quasar, will we passively accept the existence of a quasar powered by a trillion solar-mass black hole residing in a quadrillion solar-mass protogalaxy? I hope not. Will the last physicist leaving turn out the lights?

 

[Chronos]

"Tired light" is a theory that light, in its long journey from remote galaxies to us, loses energy from some unknown process, and since each photon, going to a lower energy, acquires a lower frequency, the light becomes systemattically red-shifted. This would explain the red-shifting without expansion. Tired light is beloved of creationists, who don't like expansion because you can't get it out of the Bible. But whatever Chronos wants, all the observations, the supernovae cores, the CMB, and all of it RULE OUT the tired light theory.

What? I can't believe you accused me of advocating 'tired light'! I am like so pacing around the room and cursing under my breath... I'm thinking about sending you a gallon jar of pickled squirrel heads.

 

[Chronos]

What causes redshift? There are a lot of ways to look at cosmological (distance-related) redshift. Simplistically, one could equate it to a speed of recession (Doppler-like) effect in an expanding universe. That's probably not going to work real well.

Why is that?

You might also equate it to the time that light requires to pass through present units of space-time compared to the size of the units of space-time when the light was emitted, also assuming an expanding universe.

You may wish to model redshift as a gradual loss of energy of EM waves as they traverse the EM fields of the quantum vacuum that suffuse "empty space" in a non-expaning universe. This is my preference. Halton Arp, whom I respect for his work with intrinsic redshifts, has a personal distate for this model, but I believe that it is correct and that it will ultimately allow for the reconciliation of quantum field theory with GR.

Where does the missing energy go?

Non-cosmological redshift can be caused by the interaction of EM with strong gravitational/EM fields.

How so?

Decades ago, we measured the gravitational redshift of Sirius' companion. Some people seem to ignore this result today or perhaps have forgotten the importance of it back then.

What result is that?

Today (although this interpretation is widely ignored) we are currently measuring the gravitational redshifts of the accretion zones of black holes. These are the measured redshifts of quasars.

What? Give examples.

Quasars (in the Arp/Burbidges/et al model) are gravitationally-ejected black holes that evolve, and eventually permit the formation of stars, nebulae, etc, making a new galaxy. There is an apparent evolution of quasars to AGNs and to more mature galaxies. The younger the guasars are and the smaller their accretion zones, the fainter and the more red-shifted they will appear to us. Sound familiar?

Yes, it sounds like a thoroghly discredited idea.

Before you reject this concept out of hand, please realize that the most highly redshifted quasars yet discovered (z~6.5) exhibit super-solar metallicities, suggesting that they formed out of materials at least as old as our galactic neighborhood - although our Milky Way is over 13Gy removed from that era. I too believe that quasars are ejected black holes, but that the redshift of a quasar is not a function of its age (how can a quasar know how old it is?), but that the redshift is instead a function of the density of its accretion zone. The thinner the accretion zone, the closer to the event horizon, the dimmer the luminosity and the more redshifted the EM will be.

Offer one example of a high redshifted object superimposed over a lower redshifted object.

About the popular conception of quasars: Please consider that if we accept that redshift is equal to distance, these z~6.5 monsters have to have central black hole masses equal to at least several billion Sols and reside in galaxies of approximately a trillion Sols. If quasar redshifts are intrinsic (at least in part), quasars do not have to be such monsters, and their metallicities are no longer a problem. They do not have to be hyper-luminous, yet compact enough to fit within Earth's orbit. The really big problems go away.

Is it possible that our understanding of redshift is incomplete? What do you think? When the Webb telescope and the Large Binocular Telescope come on line, and some eager post-grad measures the spectrum of an even more highly redshifted quasar, will we passively accept the existence of a quasar powered by a trillion solar-mass black hole residing in a quadrillion solar-mass protogalaxy? I hope not. Will the last physicist leaving turn out the lights?

I see no problem with 'our' understanding of redshift. Those conclusions were not reached by guess work, or naively clinging to unsupported, and discredited speculations.

 

[turbo]

Offer one example of a high redshifted object superimposed over a lower redshifted object.

Here you go.

http://citebase.eprints.org/cgi-bin/citations?id=oai:arXiv.org:astro-ph/0409215

By the way, I didn't know you were a fan of the "tired light" concept. I'm not surprised, though - only a real crackpot would have a spare gallon jar of pickled squirrel heads in the pantry. Don't you just hate running out of them when the family drops in?

 

[SpaceTiger]

http://citebase.eprints.org/cgi-bin/citations?id=oai:arXiv.org:astro-ph/0409215

I'm curious which part of that paper you think constitutes proof of the QSOs superposition in front of the galaxy. It looks to me like he just assumes it.

 

[turbo]

I'm curious which part of that paper you think constitutes proof of the QSOs superposition in front of the galaxy. It looks to me like he just assumes it.

Here is just one passage:

Despite the fact that the ULX-QSO has a much smaller X-ray count rate than the central nucleus it seems very likely that this enormously strong [OII] emission near the projected position of the QSO is due to the close proximity of this secondary source of UV/X-ray flux, i.e. the QSO is interacting strongly with the interstellar gas in the disk of the galaxy.
One possibility is that the QSO emerges from the nucleus of NGC 7319 with a component of velocity toward the observer perhaps coming slightly out of the plane on the observer’s side. The QSO then excites the lower density gas in this region (or has entrained some gas from the regions it has recently passed through).

 

[SpaceTiger]

That's ridiculous. Even he doesn't claim that it's proof. The emission can easily be a consequence of nearby star formation.

 

[turbo]

That's ridiculous. Even he doesn't claim that it's proof. The emission can easily be a consequence of nearby star formation.

A previous study of the galaxy found insufficient ionization sources - not enough star formation to do the job.

In a detailed study of the extended emission line region(EELR) in NGC 7319 Aoki et al. (1996) showed that the ionizing photon flux from the line-of-sight UV/X-ray flux is insufficient to explain the H emission line luminosity.

Is the evidence of outflow (independently discovered in 1996) coincident with the radio emission, and pointed at the QSO not confirmatory of interaction in your view?

4.3. Evidence For Outflow In The Direction Of The QSO
Our one long slit placement across the ULX/QSO with the Keck LRIS instrument confirms several of the main results of Aoki et al. (1996) as far as outflow is concerned. For example they concluded that there is a gaseous “high velocity and large scale outflow into the extended emission line region (EELR) toward the south-west direction” “coincident with the direction of the radio emission” “The velocity of the outflow comes up to 500km/sec.” In our spectrum the slit passed over the EELR to the south of the Seyfert nucleus.
Assuming that the systemic redshift of the galaxy is z = 0.0225, Table 1 shows [OII] at -210 km/sec, [OIII] at -300 km/sec and the weaker [OIII] line at -390 km/sec. Thus the outflow of the gas is very high.

How about this? Still no evidence of interaction?

4.4. The Wavelength Coincidence of the [OII] emission line in NGC 7319 with Ly in the QS O. It is remarkable that the [OII] line in the 2d spectrum of Fig. 5 closely intersects the Ly line in the QSO. Figure 6 is introduced here in order to show the exactness of this relation. The [OII] line is about 7°A (FWHM) and reaches a peak of about 3 x 10−16 erg cm−1 sec−2°A−1. The Ly line width is about 150°A (FWHM) and peaks at about 3 x 10−17 in the same flux units. It is clear that the major QSO line as well as its continuum is well placed to pump the excited state of [OII] emission.
It is also true that the 7°A (FWHM) of the [OII] line gives a velocity width of 550 km/sec. (The [OIII] 5007 line width gives 540 km/sec). This would imply that the passage of the QSO through the material of the galaxy has produced a dynamical disturbance as well as a radiative excitation.
The color picture Fig. 4 gives pictorial evidence in support of a model where the QSO has been ejected from the nucleus of the Seyfert NGC 7319. It is seen that there is a luminous connection reaching from the nucleus (just at the top of the picture frame) down in the direction of the ULX/quasar, stopping about 3′′ from it. It is also apparent that this connection or wake is bluer than the body of the galaxy.

Then read their arguments relating to relative position of the QSO and the galaxy. I find them well thought-out and worthy of more than a simple nay-saying rejection.

 

[SpaceTiger]

A previous study of the galaxy found insufficient ionization sources - not enough star formation to do the job.

I read parts of the Aoki paper it actually is extremely interesting, but not for the reasons you'd like to think. The insufficient ionizing radiation seems to imply the presence of an anisotropic radiation source from the central engine of the Seyfert. This would be consistent with the dust torus model people have been exploring in the context of AGN.

Is the evidence of outflow (independently discovered in 1996) coincident with the radio emission, and pointed at the QSO not confirmatory of interaction in your view?

Not if it was selected based on that, something which Burbidge always does for his papers. The statistics of this were hashed out long ago and there is no excess of quasars near galaxies (in angle on the sky).

Then read their arguments relating to relative position of the QSO and the galaxy. I find them well thought-out and worthy of more than a simple nay-saying rejection.

I'm sure they know better than to try to claim such a proof based on a single case.

 

[Skomatth]

Chronos, while I agree that turbo's explanation doesn't look like anything I've read from what I believe to be credible sources, you aren't helping my understanding at all-the guy turbo was responding to.

 

[Chronos]

Here you go.

http://citebase.eprints.org/cgi-bin/citations?id=oai:arXiv.org:astro-ph/0409215

By the way, I didn't know you were a fan of the "tired light" concept. I'm not surprised, though - only a real crackpot would have a spare gallon jar of pickled squirrel heads in the pantry. Don't you just hate running out of them when the family drops in?

Hehe, you never have a jar of pickled delicacies on hand when you really need one.

I remain, however, curious. Surely there must be at least one high redshift quasar ejected directly at us from the core of a low redshift mother galaxy.

 

[turbo]

Hehe, you never have a jar of pickled delicacies on hand when you really need one.

I remain, however, curious. Surely there must be at least one high redshift quasar ejected directly at us from the core of a low redshift mother galaxy.

Why "directly at us"? The example above is sufficiently compelling to cause us to investigate the "interaction" and prove or disprove it (or at least make observations enough to establish a preponderance of evidence one way or the other).

The simple nay-saying that accompanies the release of any paper by this group of gifted observational astronomers is unseemly. If the observation (the only kind of experimentation that astronomers can do) cannot be replicated, so be it. If the observation is replicated and improved upon, and we are uncomfortable with the implications of the observation, too bad. Science is not and cannot be a democratic process, where the majority rules. Sometimes people lose sight of that.

 

[matt.o]

intrinsic redshift of QSOs does not fit well with observations of clustering of galaxies around the QSO at the same redshift as the galaxies. Nor does it fit in with the observed gravitationally lensed images of high redshift QSO's by lower redshift galaxies, where the galaxy must be well in front of the QSO.

 

[turbo]

intrinsic redshift of QSOs does not fit well with observations of clustering of galaxies around the QSO at the same redshift as the galaxies. Nor does it fit in with the observed gravitationally lensed images of high redshift QSO's by lower redshift galaxies, where the galaxy must be well in front of the QSO.

Hi, Matt. Do you haved citations illustrating how galaxies cluster around the redshifts of local quasars? That would be a really interesting concept.

 

[matt.o]

it is more that the QSOs are observed in galaxy groups/clusters, not that the galaxies cluster around QSOs.

I can't remember the exact paper, I will have to get back to you.

 

[Chronos]

Why "directly at us"? The example above is sufficiently compelling to cause us to investigate the "interaction" and prove or disprove it (or at least make observations enough to establish a preponderance of evidence one way or the other).

The simple nay-saying that accompanies the release of any paper by this group of gifted observational astronomers is unseemly. If the observation (the only kind of experimentation that astronomers can do) cannot be replicated, so be it. If the observation is replicated and improved upon, and we are uncomfortable with the implications of the observation, too bad. Science is not and cannot be a democratic process, where the majority rules. Sometimes people lose sight of that.

Why not directly at us? Of the many thousands of high redshift QSO's discovered to date, why is not a single one superimposed smack in front of a low redshift 'ordinary' galaxy? Perhaps the answer is - they really are as distant as suggested by their redshift. This is not simple nay-saying, it's simple logic supported by sound statistics.

 

[SpaceTiger]

Why "directly at us"? The example above is sufficiently compelling to cause us to investigate the "interaction" and prove or disprove it (or at least make observations enough to establish a preponderance of evidence one way or the other).

When a theory's predictions have been shown to be wrong enough times, people generally disregard subsequent papers which run under the assumption of its truth. The paper you referenced picked out an observation that was indeed a bit unusual, but was a far cry from really presenting evidence for the truth of Burbidge's theory. It will be very difficult to say for sure whether this system can be described by conventional theory and it's not a good use of observing time to keep studying it. Rather, Burbidge should be looking for consistent effects or statistical deviations from the standard theory and then put together a testable prediction for other observations. Analyzing special cases like this is of little more value than waving around a picture that looks like bigfoot and claiming that it provides proof for its existence.

To be fair, he has tried to provide more general predictions in the past, but they've turned out to be wrong. One gets the impression that he's now just running off the steam of a philosophical preference.