Just one quick set of questions.
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Originally Posted by rtomes
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Originally Posted by Nereid
Paper 5 can be ignored; paper 8 is by the same authors, more recent, and explicitly includes the findings in 5. Pace rtomes, paper 8 does report null findings; for example (p458) "No significant periodicity was found for the sample of 77 irregular galaxies."
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Are these smaller galaxies? If so, then I would expect the periodicity to be a smaller cycle (like 12 km/s or 6 km/s) and the data may not be accurate enough to detect this. Tifft is clear about the need to work with different classes of objects separately. I would concur with this from a theoretical point of view in HT. If the data had unlimited accuracy this would not be a problem. Smaller irregular galaxies in the local group do seem to show a spacing of ~180,000 LY or 50-60 kpc (or multiples) from larger galaxies and each other. I have not seen an analysis of this published, but have observed this of the data. This observation is partly derived from a variety of sources. There will not be time to find all the references but want to raise this as something to watch for because such a common spacing is useful in the cosmic distance ladder.
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What is the size of the dataset (number of independent galaxy redshifts) used in paper 1? How many of the galaxies in the dataset used in paper 1 are dwarf galaxies?
Ditto, paper 2?
Ditto, paper 3?
Ditto, paper 4?
Ditto, paper 6?
Ditto, paper 7?
More generally, what is the composition of the datasets, in each paper, by type of galaxy?
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[F]rom a theoretical point of view in HT", how many classes of galaxy are there? What are they? How are they distinguished from one another?