Re: Confused about redshift and age of stars


Craig Markwardt wrote:
"Thomas Smid" <thomas.smid@xxxxxxxxx> writes:


Craig Markwardt wrote:

"Thomas Smid" <thomas.smid@xxxxxxxxx> writes:
Craig Markwardt wrote:

"Thomas Smid" <thomas.smid@xxxxxxxxx> writes:
...

I am suggesting that it is *only* the electric field that causes this.
Otherwise, it would hardly be able to cause a redshift in intergalactic
space as the distance between two particles is larger than the length
of a 'photon'.
With regard to the deflection, which I specifically treated on my page
http://www.plasmaphysics.org.uk/research/lensing.htm : as mentioned
there, the electric field around the sun should have a strength of
about 10^-6 V/m (due to the sun being positively charged at a potential
of about 1 kV) However, it extends over about 10^6 km , so you need
correspondingly higher field strengths for lab dimensions. If you
assume a quadratic dependence (as suggested on my webpage), then you
find that you would need lab field strengths of the order of the
inner-atomic field, which are obviously impossible to create (as it
would tear the whole lab apart at the same time) . The whole effect is
thus very much associated with astronomical distances and it is
therefore not surprising that it is unknown in classical mainstream
physics.

However, there are very significant problems with non-cosmological
redshifts. As I noted in sci.astro.research article
<mt2.0-2096-1113304780@xxxxxxxxxxxxxxxxxxxx> in reply to Robin Whittle,

: A non cosmological theory of redshifts would have a lot of serious
: problems to address, namely,
:
: * how cepheid variable stars, which have a known period-luminosity
: relationship in the local universe, would have a period-luminosity
: relationship in redshifted galaxies which is exactly tuned to the
: redshift of the galaxy? I.e. how would each cepheid know to tune
: its luminosity to the intrinsic redshift of the galaxy?

I assume you are referring here to an effect similar to the delay of
supernova light curves.

Actually, I'm not. You are welcome to investigate cepheids and the
related Hubble key project.

The redshift mechanism suggested by me would also result on average in
a linear redshift-distance relationship, so it doesn't make any
difference for the cepheid observations.


... I have covered this on my page
http://www.physicsmyths.org.uk/redshift.htm . Basically, in general, if
a 'stretching' of the light wave (by whatever mechanism) leads to a
redshift, this is also likely to be associated with a reduction of the
amplitude of the wave i.e. a reduction in its intensity (additionally
to the usual 1/r^2 decrease). This leads therefore to an
underestimation of the absolute luminosity of the object.

I note that there is no specific mechanism cited for either the
wavelength "stretching" or amplitude decrease.

No there is no mechanism cited, as I assume the effect to be a
fundamental one, or at least one that can't be derived from presently
accepted principles (unless you have a suggestion in this sense).


: * how could the Lyman alpha forest exist? I.e. how could absorption
: systems be seen at multiple intervening redshifts, but not at higher
: redshifts?
:
: http://www.astro.ucla.edu/~wright/Lyman-alpha-forest.html
:
: * if redshift is intrinsic to the host galaxy, how could the *same*
: Lyman alpha absorption system appear in two *different* galaxy
: spectra, which are on nearby lines of sight?
:
: Young, P. A., Impey, C. D., Foltz, C. B. 2001, ApJ, 549, 76
:
: * for Arp-like theories where the redshift is intrinsic to the
: galactic nucleus, how could maser systems exist distinct from the
: nucleus which have the same redshift as the nucleus?
:
: Kondratko, P. T., Greenhill, L. J., Moran, J. M. 2005, ApJ, 618, 618
: Herrnstein, J. R. et al. 1999, Nature, 400, 539
: Yates, J. A. et al 2000, MNRAS, 317, 28
:
: * for non Arp-like theories, where the redshift is created in the
: neighborhood of the galaxy by some gas or plasma, how could the
: redshift "process" -- whatever it is -- physically generate
: indentical redshifts at both microwave and optical wavelengths?
: I.e. all electromagnetic processes I am aware of are highly
: chromatic.

These points do not apply to my theory as it assume that the redshift
is distance related (i.e. produced progressively on its way from the
object to the observer due to the effect of the intergalactic plasma).

:
: * for that matter, how could any "plasma effect" shift the wavelength
: of emission, without doing other things like line broadening?
: I.e. why aren't high redshift lines also highly broadened?

This would only apply in case of a scattering, but not for a mechanism
that can be compared to refraction. As shown on my page
http://www.plasmaphysics.org.uk/redshift.htm , the 'blurring' of the
signal can be completely neglected here.

So what is this mechanism exactly? Your web page only suggests "if
this were possible" type scenarios, but no specific mechanism. I
suspect that there is no detailed theory behind the wishful scenario.

The exact 'mechanism' could be worked out if the effect is studied in
more detail. At the moment I am just suggesting, as you said, as a
possible scenario i.e. that the redshift and bending of light is
associated with electric fields.

However, since you claim it is a "fundamental" effect, there is no
reason to associate it with electric fields. Why not magnetic fields?
Or for that matter, why not magic pixie dust?

Well, if you could show that you can relate both the redshift and the
bending of light to magnetic fields or pixie dust, then this would also
be a theoretical possibility. In contrast to the electric field, I
can't see however how one could plausibly justify these.


[e.g. "fundamental" principle of linear superposition implies
that electric fields do not interact].

Light is an electromagnetic field, not just an electric field. It is
known to interact for instance with magnetic fields (e.g. Faraday
rotation), so why should it not also interact with electric fields?




:
: * why the cosmic microwave background in the high redshift universe
: was apparently hotter?
:
: Molaro, P., et al. 2002, A&A, 381, L64
: Silva, A. I. & Viegas, S. M. 2002 MNRAS, 329, 135
: Srianand, R. Petitjean, P. & Ledoux, C. 2000, Nature, 408, 931

I had a look at two of the papers and I think this should not really
count as hard evidence.

Interesting and ironic, given your own lack of hard evidence.

I am suggesting my theory merely as a proposal, but these papers
misleadingly suggest that their data would be evidence for an increase
of the CMB temperature. This is by no means the case as one can see for
instance from Fig.5 in Srianand et al. (see
http://www.plasmaphysics.org.uk/imgs/srianand.gif ). I have allowed
myself here to make this plot somewhat clearer by putting explicit
error bars to those measurements that merely were estimates of upper
limits (and I also corrected the figures on the temperature scale which
originally read 30-20-30). First of all, since the COBE measurement at
z=0 has nothing to do with the type of analysis at question here, it
should not serve as further constraint for the data, and without it
almost any curve could be a fit, for instance a constant temperature of
8 K (the long-dashed line that I put in additionally). The latter
possibility would then of course indicate that the observed fine
structure excitations are not related to the CMB at all.

Are you really suggesting that the present-day (z=0) cosmic microwave
background temperature is not 2.73 K?

Where did I say this? What I said is that the excitation of the
interstellar molecular fine structure levels has nothing to to with the
CMB temperature.


And are you aware that the same kinds of techniques used to measure the
CMB temperatures at high redshift were originally used to measure the
local CMB temperature? (see Thaddeus, Herzberg, McKellar references
below, also Roth, Meyer & Hawkins 1993, ApJL 413 L67).

You shouldn't take all claims made in scientific publications at face
value. It is quite obvious that the data analysis in these papers has
been massaged such as to get the desired result. It is for instance
quite revealing that after Penzias and Wilson's discovery of the (then)
3.5 K background radiation in 1965, the value derived from the
observations of the molecular fine structure excitation suddenly went
up from the 2.3 K (as derived by McKellar in 1940) to Penzias and
Wilson's value (e.g. Thaddeus and Clauser, 1966,
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19900066961_1990066961.pdf
). Now after the CMB temperature was revised to 2.7 K, suddenly the
lower values are in fashion again. I think everybody can see what is
going on here. The point is that there are so many estimates and
assumptions applied in these papers (most of them questionable in one
way or another) that you can basically derive almost any temperature
from the data if you want.

And are you
aware that the 2.73 (1+z) line shown on the plot you refer to is *not*
a fit?

Well, it does fit the data apparently, but it is hardly a 'best fit'.
Only in the latter case could you rightfully claim that you confirmed
the theoretically predicted increase of the CMB temperatute with z. But
evidently, this is not the case.




... There are a lot of assumptions and estimates
being made which are based on observations within our own galaxy and
thus may not be appropriate for QSO's. ...

Again, interesting in light of your own unsubstantiated assumptions
and estimates. The papers I cited have quite extensive citations
themselves. You could have checked this out, but apparently you did
not.


... The excitation of certain fine
structure transitions may well be due to local microwave sources for
instance. ...

True, but these papers also consider those possibilities and estimate
the contributions of local sources. Do you have a substantiated
correction to that?

... Also, they may have underestimated the excitation due to
collisions by electrons by assuming the latter to be in LTE with the
ions and neutrals. This assumption is far from correct for most space
plasmas as photoelectrons usually recombine before they thermalize
owing to their small mass (see for instance my own numerical
calculation for the ionospheric electron spectrum at
http://www.plasmaphysics.org.uk/research/elspec.htm ).

Some of these factors are discussed in the papers. Meanwhile, you
have provided no quantitative counterargument.

The physical assumptions made in these papers are very much
inappropriate and/or incorrect:

1) There is no way that photoelectrons of around 10 eV could lose
sufficient energy such as to end up with a kinetic temperature of
around 10^-2 eV (100K) (as assumed in these papers). Due to the mass
...

Huh? Since the cited papers deal with excited *fine structure*
states, photoelectrons really have nothing to do with the basic
process. The fine structure states are excited by the CMB.

No, you are getting this wrong. Photoelectrons of several eV can
excite the upper levels of the observed lines, from which the atom then
decays into the various fine structure levels of the ground state. With
electron energies corresponding to 100 K or so (as assumed in these
papers), this would obviously not be possible.

Anyway, it is in fact nowhere theoretically shown in these papers that
the CMB could lead to any significant population of the fine structure
levels. The method applied there is as follows: they observe a certain
population of the fine structure levels, then they try to estimate (by
means of a host of questionable assumptions) the contributions to the
level population from all other sources *apart* from the CMB, and then,
because they find these are insignificant, conclude that it must be
caused by the CMB (without even having a quantitative theoretical basis
for this suggested mechanism).


2.) It is assumed in these papers that the fine-structure levels are
populated according to a Boltzmann distribution. This would require
that elastic collision time scales are shorter than the life time of
the levels.
...

Huh^2? Molecular/ionic collisions are not required for the Boltzmann
equation to apply. Since the states in question are directly excited
by the CMB, your comment is irrelevant.

Presumably you mean the 'Boltzmann distribution' ('Boltzmann equation'
is something else (see http://www.plasmaphysics.org.uk/#boltzequa )).

The requirement for a Boltzmann distribution (including the ground
state) is a collisionally determined situation (both excitation and
de-excitation). It can in general not be produced by radiation (even a
Planck spectrum would only result in an exponential decrease of the
excited level population in the Wien region of the spectrum; however,
for instance for Carbon the lowest excited fine structure level is only
2*10^-3 eV above the ground state, which would require excitation by a
wavelength of about 0.6 mm i.e. close to the maximum of the 2.7 K
Planck curve (and thus the excitation probability compared to other
levels would not be a simple exponential factor).




3.) The figures used in the papers do in fact not add up at all: in
Ge,J., Bechtold,J. and Black,J.H. , ApJ. 474, 72 (1997) for instance,
the H-ionization photon flux appropriate for the observation is given
as about F= 10^8 ph/cm^2/sec .
...

Since photo-ionization is not the fundamental process in question,
your comment here is also irrelevant. [ However, in some of the
papers, photoionization is discussed as an indirect source of
electrons which make collisions. ]

Photoionization is dicussed, but obviously if invaild assumptions are
made, the discussion can only lead to incorrect conclusions.



I am also missing any observations that would correspondingly derive a
temperature of 2.7 K from objects within our own galaxy (where the
physical conditions are obviously much better known).

You mean like these?

Herzberg, G. 1950, *Molecular Spectra and Molecular Structure*,
v. 1, 2nd Ed., (van Nostrand: Princeton, NJ) -- p. 496
McKellar, A. 1940 PASP 52, 187
McKellar, A. 1941, Publ Dominion Astrophys. Obs., Victoria, BC, 7, 251
Thaddeus, P. 1972, Ann. Rev. Ast. Ap., 10, 305

No, actually I meant that the analysis of any of the methods used to
derive the CMB temperature in certain extragalactic objects is applied
identically to other objects including ones in our own galaxy. It is in
my opinion scientifically improper to apply any of these observational
methods basically only to one instance and then claim that these
provide mutual confirmation if they happen to yield the expected
result.

This is not really a relevant critique. For one thing, the "old"
methods of measuring the local CMB noted above are quite similar to
the measurement methods used for the high redshift universe. One of
the primary differences is the species and transition being measured.
However, since the CMB at high redshift is actually a cosmic optical
or UV background, different transitions sensitive to shorter
wavelengths would have needed to be chosen anyway.

I should also mention that the redshift dependence of the CMB
temperature has also been confirmed with galaxy clusters (Battistelli,
E. S., et al. 2002, ApJL, 580, L101).

This is based on the Sunyaev-Zeldovich effect, which I think is not yet
sufficiently observationally confirmed, because as far as I am a aware,
the predicted increase of the CMB intensity in the high frequency
region has not been observed yet at all. ...

It's pretty convenient for you to declare what is sufficiently
observationally confirmed. It's quite impressive that the SZ
measurements to date have confirmed the basic cosmological parameters.

As far as I am aware, the SZ effect has not been confirmed in the Wien
region of the spectrum as yet (where it should lead to an increase of
the CMB intensity rather than a decrease as for the lower frequencies).



... On the other hand, the
decrease for lower frequencies would also result from my own theory: as
mentioned already on my page
http://www.plasmaphysics.org.uk/research/redshift.htm , the plasma
should lead to electromagnetic waves gradually being 'scrambled' i.e.
their coherence and thus their apparent intensity being reduced (see
http://www.plasmaphysics.org.uk/photoionization.htm ). So any
microwave radiation passing through a cluster would be appear as weaker
than that not passing through the cluster.

But as noted above, and as you admit yourself, your "theory" is not a
theory at all. It has no independent basis in experiment; is not
borne out or connected to any other theory; it's just wishful
thinking. Meanwhile, the theoretical physics underlying the SZ effect
-- Comptonization -- is well tested and understood.

. . .

I also note that you conveniently deleted several sections of the
previous post.
Recapping those missed points:
* you don't provide any detailed mechanism of how electromagnetic
radiation could be redshifted *or* bent by "electric fields"
* no explanation of how significant static fields could exist
in intergalactic space to cause redshifts
* your "theory" has an implicit dependence on wavelength [*] and yet
cosmological redshift does not
[*] - "it is reasonable to assume that the redshift (as well as
the angular deflection) is not only proportional to the electric
field, but also to the wavelength as the potential difference
between two wave crests is proportional to it."
http://www.plasmaphysics.org.uk/research/lensing.htm

I have commented on these points already before.

Finally, it is worth noting that while there has long been known to be
a charge separation effect in the sun which produces an electric
potential (Eddington 1926, *The Internal Constitution of Stars*,
Cambridge Press), it is far smaller than you suppose (Neslusan 2001,
A&A, 372 913). Following the very simple derivations therein, the
effect is perhaps 10 Volts, not the 1 kV that you simplistically
derived by setting the gravitational potential energy equal to
electrostatic.

Where do you get the 10 Volts from? The paper (
http://www.edpsciences.org/articles/aa/pdf/2001/24/aah2649.pdf )
arrives at the result that the electric force corresponds to 50% of the
gravitational force for protons. Now the gravitational energy of a
proton near the sun's surface is 2 keV i.e. the electric potential is 1
kV according to this as well.


Thomas

.

Relevant Pages

  • Re: Confused about redshift and age of stars
    ... I am suggesting that it is *only* the electric field that causes this. ... it would hardly be able to cause a redshift in intergalactic ... structure excitations are not related to the CMB at all. ... electrons which make collisions. ...
    (sci.astro)
  • Re: Confused about redshift and age of stars
    ... I am suggesting that it is *only* the electric field that causes this. ... it would hardly be able to cause a redshift in intergalactic ... collisions by electrons by assuming the latter to be in LTE with the ...
    (sci.astro)
  • Re: Confused about redshift and age of stars
    ... I am suggesting that it is *only* the electric field that causes this. ... it would hardly be able to cause a redshift in intergalactic ... I had a look at two of the papers and I think this should not really ... collisions by electrons by assuming the latter to be in LTE with the ...
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  • Re: Confused about redshift and age of stars
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