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- Xref: sparky sci.physics:22652 sci.astro:13901
- Path: sparky!uunet!mcsun!uknet!comlab.ox.ac.uk!oxuniv!clements
- From: clements@vax.oxford.ac.uk
- Newsgroups: sci.physics,sci.astro
- Subject: Re: The Big Bang Never Happened
- Message-ID: <1993Jan12.112110.11223@vax.oxford.ac.uk>
- Date: 12 Jan 93 11:21:10 GMT
- References: <wwadge.726349985@csr> <1ifqfrINNd6l@terminator.rs.itd.umich.edu> <C0JL5B.6s4@well.sf.ca.us> <1993Jan11.162143.3232@s1.gov>
- Organization: Oxford University VAX 6620
- Lines: 121
-
- In article <1993Jan11.162143.3232@s1.gov>, lip@s1.gov (Loren I. Petrich) writes:
- > In article <C0JL5B.6s4@well.sf.ca.us> metares@well.sf.ca.us (Tom Van Flandern) writes:
- >>
- >>wwadge@csr.UVic.CA (Bill Wadge) writes:
- >>
- > : [Lerner's] book is very persuasive, but I'm not a physicist - any opinions?
- >
- >>and rhine@bigbird.csd.scarolina.edu (Andrew P. Rhine) writes:
- >
- > : it would seem that opposition to the big bang would have been dealt a major
- > : blow by this year's results from COBE and recent observations (by the
- > : balloon-based instruments) supporting it.
- >
- >> Not at all, Andrew. Finding marginal but significant fluctuations in
- >>the microwave background radiation saved the big bang for the moment, but did
- >>no damage to alternatives. Especially, it does not bear on Lerner's "proof"
- >>that the microwave radiation must be coming from relatively local sources,
- >>and can have nothing to do with a big bang fireball. The essence of his
- >>argument is that galaxy luminosity differences between infrared and radio
- >>wavelengths show intergalactic absorption at such a level that the microwave
- >>radiation could not penetrate through more than about z = 1 or so, let alone
- >>the z = 10,000 or so required by the big bang. [E.J. Lerner, Astrophys. J.
- >>361, 63-68 (1990).]
- >
-
- [Interesting discussion of intergal;actic extinction in a real universe with GR
- deleted, but I think it makes some good points that Lerner has not addressed]
-
- Its nice to see this discussion again, but I'm interested that it seems to have
- gone to sci.physics from sci.astro. Was there too much heat in sci.astro for
- the anti-BB camp? I'd appreciate followups sent to sci.astro as I don't get
- sci.physics anymore.
-
- Anyway, this has woken me up again, and at last I will get around to posting my
- objections to Lerner's paper whic, I have to admit, I promised Tom about 6
- months ago...
-
- Lerner's paper is based on IRAS and radio data for a range of galaxies at
- various distances. He uses the well known far-infrared (FIR)- radio flux
- correlation relation (Helou Soifer & Rowan-Robinson ApJ. 298 L7) to predict a
- galaxy's FIR flux based on its radio flux. He then calculates the difference
- between observed and predicted FIR flux and finds a correlation between this
- difference and galaxy redshoft. This is used ti infer that the FIR emission is
- beign reduced in the more distant galaxies by absorption in the intervening
- intergalactic medium.
-
- There are a number of problems with this result which I will now describe. They
- are not inescapable difficulties, and further work may be able to get round
- them, but at this stage they are grounds for serious doubts on the paper's
- conclusions, especially since these conclusions have wide reaching implications
- for the CBR and the Big Bang. My doubts are as follows:
-
- (1) The correlation coefficient for the decrease in FIR flux with redshift is
- only 0.35 (it would be 1 for a perfect relationship), and there is visually a
- great deal of scatter in the diagram. While such scatter might be expected
- given the usual uncertainties with observational data, the scatter here is not
- random. The bulk of the scatter is at the higher redshifts where the bulk of
- the data lies. Worse than this, the marority of the correlation comes from a
- small number of points at low redshift (very close to our own galaxy). Indeed,
- if you remove the nearest 10 objects from the plot, visually the correlation
- seems to go away. I have not done the statistics on this, but the change is
- clear to the eye. This suggests to me that the 'correlation' is actually some
- artifact introduced by some problem with the nearby objects, which makes them
- seem to have either too much FIR flux, or too little radio emission.
-
- (2) Two separate methods are used to extract the FIR data from the IRAS
- satellite; ADDSCAN and COADD. The exact differences are not important, but the
- applications of these methods is. ADDSCAN is used for more distant, smaller
- galaxies, while COADD is used for nearer objects extended beyond 8'. There are
- known to be systematic differences between the fluxes produced by these two
- methods (I don't have a reference for theis I'm afraid. It was brought up at
- the NATO ASI on Clusters and Superclusters in summer 1991). This could easily
- account for the shift of the nearer objects relative to the more distant ones.
-
- (3) There is a significant contaminating foreground componant in our galaxy,
- the IRAS Cirrus, which can contaminate the integrated fluxes of large objects,
- and so make them seem brighter in the FIR than they actually appear. This will
- be especially problematic if the nearby objects are selected close to the
- galactic plane, which they seem to be from Lerner's object lists.
-
- (4) Of the closest 10 or so galaxies which I checked in catal;ogues, there are
- problems with at least 4 of them. It should be noted that the radio-FIR
- relationship seems only to work for spiral galaxies and those exhibiting a
- significant star formation rate. Other objects might not fall on the relation,
- ruining any results that assume they do. The problems are:
-
- NGC55 This has a multiple nucleaus and so is probably not a spiral. Quite what
- it is is unclear.
-
- NGC110 is not a galaxy but a star cluster and so should not be included.
-
- NGC 1569 is an Arp peculiar galaxy, and so should not e included.
-
- NGC 3077 is an elliptical, a class of galaxy Lerner specifically excludes from
- the sample.
-
- These classifications are all based on NGC, and remove 4 of the closest 10
- objects, already reducing the significance of the total correlation. I have not
- investigated further due to lack of time, but I suggest that these problems all
- suggest that the Lerner result is not as cast iron as TVF and others seem to
- think it is.
-
- It would be interesting to have Eric Lerner's comments on these issues.
-
- Best wishes,
- Dave
-
- >>Tom Van Flandern / Washington, DC / metares@well.sf.ca.us
- >>Meta Research was founded to foster research into ideas not otherwise
- >>supported because they conflict with mainstream theories in Astronomy.
- >
- > --
- > /Loren Petrich, the Master Blaster
- > /lip@s1.gov
- --
- ================================================================================
- Dave Clements, Oxford University Astrophysics Department
- ================================================================================
- clements @ uk.ac.ox.vax | Umberto Eco is the *real* Comte de
- dlc @ uk.ac.ox.astro | Saint Germain...
- ================================================================================
-