Fine structure constant probably doesn't vary with direction in space!

TrickyDicky

Fascinating stuff, thanks.

twofish-quant

But you could have a situation where there are lots of small electric fields. Say caused by black holes.

That's the overall field. If the objects are 10 pc to 100 pc and an area of active star formation, it's very easy to imagine large numbers of black holes generating very strong magnetic fields.

twofish-quant

MECO is just a name for black holes by people that don't understand general relativity and don't understand that black holes can have strong magnetic fields. Quasars *are* huge star-like objects with an extremely intense magnetic field, rapid spin and an intrinsically redshifted luminous surface.

The fact that the objects are uniformly distributed suggests otherwise. Also you can tell the temperature from the clouds and if they are rapidly moving with respect to a magnetic field, you should seem massive synchrontron radiation.

twofish-quant

It's not that unexpected. Given that we have no idea how supernovas actually explode, the fact that you can have a 40 solar mass star turn into a neutron star is not *that* unexpected. Also the MECO paper is pretty much non-sense. The people writing it don't understand GR.

Also a varying alpha isn't that weird.

turbo

Don't say that too loudly. Intrinsic redshifts in quasars are the third rail of astronomy/cosmology. Any hint that two physically-associated astronomical bodies might have widely discordant redshifts will get you marginalized in short order.

twofish-quant

Right, and alpha happens to be the value of coupling constant when the energy scale is zero. The thing is that the fact that the energy scale is zero is quite arbitrary. Zero is the energy that you have when you are in a vacuum, and there is no particular reason that the vacuum ended up at this energy level rather than at some other one.

One thing that you could argue in 1995, is that the energy level would settle at some value that would level space time "flat" but the discovery of the accelerating universe calls that into question.

It would. If alpha happens to be the result of the vacuum energy level being what it is, then you don't expect causally different parts of space time to settle necessarily to the same energy level.

VelocideX

How do you explain the fact that the host galaxies of the quasar absorbers can be identified in many cases?
e.g. http://adsabs.harvard.edu/abs/2008A%26A...487..583B

Also, this does also does nothing to explain the Lyman-alpha forest -- the dense series of Lyman alpha transitions along the line of sight to the quasar which all occur below the Lyman alpha emission peak. High column density Lyman alpha absorbers have been identified with host galaxies at cosmological redshifts. Hydrodynamic Lambda-CDM simulations reproduce the observed statistical properties of the forest as far as I know. No-one takes the gravitational redshift explaination for quasar sources seriously anymore.

twofish-quant

That's funny because I don't recall anyone asking me to turn in my astrophysics card when we talk about this sort of stuff at lunch.

Suggesting that associated astronomical bodies *might* have discordant redshifts won't get you looked at funny. It's when you telling that the person you are talking to that they are an idiot and part of an evil conspiracy that will get you problems.

twofish-quant

Yup.

And one point that I'm trying to make here is that while "quasars are caused by gravitational redshift" is considered a nutty idea by people in the field, the idea that "the fine structure constant may be varying in space and time" isn't, and there are theoretical reasons why you are getting telescope time to look at this whereas as the gravitational redshift people aren't.

turbo

What do you think of NGC 7603? Cosmic coincidence, chance projection, or a real viable example of 4 interacting astronomical bodies (excluding the bridge as an entity) having a wide range of redshifts.

My co-conspirators and I are taking baby-steps, studying redshift differentials in M-51 type galaxy associations. Getting published is easy. Getting people to think about the implications is a bit more problematic.

twofish-quant

One other question. Have you tested your code to see what happens if you do have stray electric and magnetic fields? The general electric and magnetic field in the IGM might be microGauss, but if you have a large number of black holes and neutron stars in the cloud, you can easily get tesla level magnetic fields within the cloud.

Not to say this is a bad thing. Discovering that clouds are highly magnetized is as interesting as finding a varying alpha.

VelocideX

What would be the origin of large numbers of neutron stars and black holes in the IGM?

Old Smuggler

It seems that I did not express myself clearly enough. What I had in mind, was a theory of varying
alpha in flat space-time. How do you construct such a theory compatible with SR? Even if you
could declare a preferred inertial frame in flat space-time, it would be arbitrary.
That is not a preferred frame in the sense we are discussing here.

A preferred frame could be part of the gravitational physics of some metric theory of gravity without
violating the EEP (but the SEP would be violated). In that case, the preferred frame cannot be
detected by doing local non-gravitational experiments. If it can, the the preferred frame must be part
of some flat space-time theory to fulfil the EEP.

Of course, according to GR, the frame of the CMB is preferred in neither way, it is just a frame where
a lot of stuff is at rest, on average.
That's part of the gravitational physics, and is consistent with GR with an exotic energy field as
source. A time-shifting alpha raises more fundamental problems.
A preferred frame that can be detected locally, by gravitational or non-gravitational experiments,
does indeed break GR.
This seems too speculative for my taste. Anyway, the problem is also how alpha varies in vacuum.

Old Smuggler

But what does the variation of the X-field depend on? Is there a theory of the X-field in flat
space-time? It seems that all you have done, is to transfer the problems of varying alpha to the
X-field.
I am inclined to believe that the universe has some fundamental properties. The reason why alpha
does/does not vary might well be one of them. And I cannot really see that you have answered my
specific concerns regarding varying alpha. Note that I do not say that the idea of varying alpha is
"nutty" or something like that, I just claim that it is radical, and with no particular theoretical motivation
how to change the mainstream framework to implement it. To me, this seems to signify another dead end.
We seem to have very different philosophies how to do science. I prefer parsimonity combined
with a careful assessment of observational results. That is, any extra assumptions specifically made
to make observational results fit theory, is regarded with strong suspicion. Besides, I am well aware
that what is presented as observational "facts" may well depend crucially on theoretical assumptions
made when analyzing the data. Therefore it is important to analyze data within different frameworks.

Since our views do not seem to converge, I think it's just as well to stop here, and just agree to
disagree.

twofish-quant

You said yourself that the clouds were likely to be in the halo of galaxies. You have a self-gravitating cloud of hydrogen. It's likely that you will have massive star formation. In any case you know that there has had to have been some star formation in the clouds. Otherwise how did the Mg and Fe get there?

So what I'm proposing is that you have these clouds of Mg and Fe because they were undergoing massive star formation, and if that's the situation then you should have large numbers of black holes and neutron stars in the clouds.

I think it's going to be rather difficult for you to come up with a scenario in which you have strong Mg and Fe lines in which you don't have some neutron stars or black holes floating around somewhere from the supernova that produced those elements.

Also should I infer from the line of questioning that you haven't done an experiment to see if stray magnetic or electric fields will cause some effects mimicking a change in the fine structure constant? If you haven't or if you have and it turns out it does, then I think you should mention in the paper that you are assuming that the clouds don't have strong magnetic or electric fields in them.

twofish-quant

At that point we are in the world of string theory, and supersymmetry in which you can make up a dozen fields, and no one will mind.

Maybe it's because we are in different fields. The problem is that in my field (supernova research) parsimonity just doesn't work. There are about twenty different things happening and they all interact with each other.

When you are in the world of GR, you can get away with parsimonity, but that comes at the cost of ignoring much of the rest of the universe. Once you get out of the nice clean world of GR into the messy real work, then parsimonity just doesn't work.

VelocideX

Large scale electric fields have never been observed in astrophysics AFAIK. The issue of magnetic fields was dealt with in a 2001 paper on systematic effects and the statements made were uncontroversial then. The magnetic field strength in the strong absorbers has been inferred from Faraday rotation and is just too small.

As I noted earlier, our paper only has 4 pages. Even the long forthcoming paper doesn't describe everything in detail. All our current papers refer to the 2003 paper on systematics, which itself refers to the 2001 paper on systematics.