Clarissa's Blog

2 responses to “Big Bang in Question”

1. 

   mitchellporter

   August 20, 2022

   There is a serious criticism that can be made of modern cosmology, but Lerner’s is not it. The big bang theory is ultimately based on two things, that all distant galaxies show light shifted into the red, and that Einstein’s theory of gravity predicts expansion of the universe, which has galactic redshifts as a side effect. For the universe to not be expanding, you need something to cancel the expansion effect, and you need some other explanation of the red shift. I don’t doubt that such models can be contrived, by postulating new fields with the necessary properties, but I see no empirical incentive to do so.

   On the other hand, there is a modified theory of gravity called MOND which does cleanly predict some things, which emerge as a kind of coincidence in ordinary dark matter models. It doesn’t mean that dark matter is definitively wrong, but it does imply that if dark matter is there, it’s coupled to the ordinary matter in a far more profound way than the usual models imply.

   I mention this because there really is a systematic barrier to MOND getting appropriate consideration, which is that it’s too easy to keep modifying the dark matter models. You can just keep modifying various phenomenological parameters to do with galactic gas flows and so on, and thereby avoid facing the paradigm shift implied by MOND’s predictive successes. The astronomer Stacy McGaugh has some of the best material on this topic.

   So I’m saying that MOND is the real sign of a structural problem in cosmological theory, and a future paradigm shift, but Lerner’s big-bang skepticism is not compelling at all. The astrophysicist he quotes (Allison Kirkpatrick. @AkAstronomy on Twitter) is not even talking about the big bang, but about theories of galactic formation. Hopefully someone will write a technical rebuttal to the specific issues he brings up.

   (My own attempt in that direction: About galaxies not looking bigger at distances beyond the “angular diameter turnover point”, it’s just his opinion that GHZ2 aka GLASS-z13 couldn’t possibly be that small; and meanwhile another galaxy seen before JWST, GN-z11, is considered to be evidence that the effect is real. As for the lack of half-merged galaxies, this may be something that the MOND people can explain, since in MOND, galactic mergers take place much more quickly.)

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2. 

   Post Alley Crackpot

   August 20, 2022

   So this idea that the universe is aged only as old as Earth-based observers can see rears its head again …

   If the Big Bang spewed out large amounts of tachyons, the temporal effects would be substantial, and in terms of Earth-based observers, the cosmic viewing screen that’s present wouldn’t end at the edge of the universe, but instead would be cut off at a specific point in time because parts of the universe moved away at FTL speeds during their creation.

   Given the vast distances between galaxies, this would mean there would be a considerable amount of time before something totally unexpected and new would be visible to Earth-based observers, meaning that looking for it during the Grand Age of Giant Telescopes doesn’t necessarily lead to discoveries or even understanding.

   And so there may be nothing to red shift.

   There really would be no “there” there to be observed yet if this is the case.

   And also there’s nothing solid about this whole fourteen billion years guesstimate that’s been thrown around since the 1980s, that’s just another irritation on top of other irritations.

   But hey, soundbite, get your fresh hot soundbite.

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