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Redshift Mechanisms and Supernova Lightcurves

  1. Mar 3, 2004 #1
    I came across Ned Wright's webpage
    http://www.astro.ucla.edu/~wright/tiredlit.htm which states that
    alternative explanations for the redshift of galaxies would not be
    consistent with the z-dependence of supernova lightcurves. However,
    this assertion is not further substantiated and as far as I can see
    any wavelength independent redshift mechanism should indeed result in
    the change of the supernova lightcurves:

    Consider a sinusoidal lightwave modulated by a lightcurve L(t), i.e.
    E(f,t)=E0*sin(f*t)*L(t) .
    By expanding L(t) into a Fourier Integral i.e.
    L(t)= Int[dF*cos(F*t)*a(F)]
    and drawing the sine function under the integral one gets
    E(f,t)=E0* Int[dF*sin(f*t)*cos(F*t)*a(F)].
    Using the addition theorems for trigonometric functions, this is
    equivalent to (apart from a constant factor)
    E(f,t)=E0* Int[dF*(sin((f+F)*t) + sin((f-F)*t)*a(F)].
    Applying now a redshift factor (1+z) changes the frequencies to
    (f+F)/(1+z) and (f-F)/(1+z), i.e. the signal becomes
    E(f,t,z)=E0* Int[dF*(sin((f+F)/(1+z)*t) + sin((f-F)/(1+z)*t) *a(F)],
    and by reversing the addition theorem and taking the sine- function
    out of the integral again
    E(f,t,z)=E0* Int[dF*sin(f/(1+z)*t)*cos(F/(1+z)*t)*a(F)] =
    = E0*sin(f/(1+z)*t)* Int[dF*cos(F/(1+z)*t)*a(F)] =
    = E0*sin(f/(1+z)*t)*L(t/(1+z)).
    This means that not only is the wave frequency redshifted but also the
    light curve broadened.

    For anyone intererested, I have myself suggested that the redshift of
    galaxies is in fact caused by the small scale electric field due to
    the intergalactic plasma (a kind of counter-part to the Faraday
    -rotation in a magnetic field) (for more details see
  2. jcsd
  3. Mar 4, 2004 #2
    very good read
  4. Mar 5, 2004 #3


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    Since there are well over 100k reliable galactic redshifts (2dF alone has >200k), I can only assume Thomas2 is referring to independent distance determinations. The best data are from the http://arxiv.org/PS_cache/astro-ph/pdf/0012/0012376.pdf [Broken], which used Cepheids to determine distances to 23 galaxies. Other data are from the Tully-Fisher relation, the fundamental plane of elliptical galaxies, Type Ia supernovae, and gravitational lenses (all but the last are discussed in the Freedman et al paper, linked above).

    While alternative explanations are always welcome, Thomas2's idea would leave a very great deal of 'unexplaining' to do.

    [Note to Phobos: this is, IMHO, a quintessential Theory Development thread]
    Last edited by a moderator: May 1, 2017
  5. Mar 7, 2004 #4

    You should doubt everything that allows a singularity in its beginning. And that is where the standard interpretation of redshift leads us. What if light ages and expands on its way from the distant galaxies, as shown in Savov's theory of interaction.
  6. Mar 7, 2004 #5
    The expansion interpretation of redshifts does not necessarily lead to a singularity or does it necessarily lead to a temporal beginning
  7. Mar 9, 2004 #6
    The expansion of the ageing light photon creates redshift. This expansion is similar to that of the much larger sources of interaction, which depending on their size create what we observe as space, time, cosmic bodies, etc. and then describe in the models of the universe [1].

    There is no such thing as tempral beginning. Simply the all-building souces of interaction appear in different sizes to create what we see as space, time and everything else [1].

    Savov, E., Theory of Interaction, Geones Books, 2002.
    Last edited: Mar 9, 2004
  8. Mar 10, 2004 #7


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    Moving this topic to the Theory Development forum.
  9. Mar 10, 2004 #8


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    Can you give a link to a peer-reviewed paper?

    If not, how about some equations which link 'the ageing light photon' with redshift?

    In Savov's idea, what is the CMB? How to account for its angular power spectrum?

    Can Savov predict the (rest) mass(es) of the neutrino(s)? How about the Higgs? the lightest supersymmetric particle?
  10. Mar 10, 2004 #9


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    Data which supports your prediction? You may wish to use that published in one or more of the large redshift surveys, and the high-z supernova searches.

    BTW, how do you account for the CMB?
  11. Mar 29, 2004 #10
    This is not my prediction but what is claimed to be observed by cosmologists (see http://www.astro.ucla.edu/~wright/tiredlit.htm ). They claim that the observations could only be reproduced by the Big Bang model, which is clearly incorrect as the purely mathematical argument in my opening post shows. For a further discussion on this issue see the Google's sci.astro.research newsgroup in which Ned Wright's further arguments are clearly invalidated.
    Last edited by a moderator: Apr 20, 2017
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