tag:blogger.com,1999:blog-2361412992308994774.post2350735553584871850..comments2023-11-19T19:19:12.773-05:00Comments on Dealing with Creationism in Astronomy: Quantized Redshifts. IX. Testing the Null HypothesisW.T."Tom" Bridgmanhttp://www.blogger.com/profile/10889134728080314165noreply@blogger.comBlogger2125tag:blogger.com,1999:blog-2361412992308994774.post-63110543193436978152011-03-21T19:06:26.255-04:002011-03-21T19:06:26.255-04:00There's loads of other things I could do to ma...There's loads of other things I could do to make this <i>more</i> realistic. <br /><br />At some point I'd like to do an experiment of what a real quantized dataset would look like with proper power-spectra methods, but that is beginning to look like a fairly major effort and will probably be delayed to a later time.<br /><br />As you'll see in the next post, even this simple simulation exhibits characteristics surprisingly similar to the N-z distributions used in many quantized-redshift analyses.W.T."Tom" Bridgmanhttps://www.blogger.com/profile/10889134728080314165noreply@blogger.comtag:blogger.com,1999:blog-2361412992308994774.post-56747493640631110102011-03-21T03:14:05.260-04:002011-03-21T03:14:05.260-04:00Somewhat off-topic, but it turns out that simulati...Somewhat off-topic, but it turns out that simulating observations of galaxies isn't quite as straight-forward as it might seem!<br /><br />Here are some aspects of the real observations which can - and undoubtedly have - caused problems for those searching for galaxy-redshift patterns (no way intended to be a comprehensive list):<br /><br />* sky distribution is distinctly anisotropic; e.g. there is a Zone of Avoidance (i.e. the plane of the Milky Way)<br /><br />* as galaxies are not, usually, point sources, there will inevitably be overlaps; robustly addressing the biases that overlaps introduce is anything but trivial (SDSS' DR8 reports a particularly challenging consequence: subtle photometric offsets quite some distance (on the sky) from bright galaxies; this affects galaxy-redshift research because it introduces a non-uniform magnitude limit, of a kind guarranteed to produce spurious associations!)<br /><br />* 'galaxy evolution'; if, on average, galaxies change as they age (or, somewhat equivalently, with distance from us, or redshift, or ...), then there will almost certainly be some sort of galaxy-redshift trend (beyond a Hubble relationship one). Depending on the details of how galaxies 'evolve', this may show up, in the observational data, as something resembling redshift quantisation.<br /><br />NereidAnonymousnoreply@blogger.com